Energy Storage Grand Challenge South-Southwest Workshop (Text Version)

Below is the text version of the May 19, 2020, Energy Storage Grand Challenge South-Southwest Workshop presentation. View a recording of this presentation.

Ladies and gentlemen, good morning and good afternoon, depending on where you are joining us from. Welcome to the Energy Storage Grand Challenge regional workshop for the South and Southwest. We are pleased to have all of you here with us today. I am Meredith Braselman with ICF Next and our team will be guiding you through the workshop today.

First, a few housekeeping items. This call is being recorded and may be posted on the DOE's website or used internally. If you do not wish to have your voice recorded, please do not speak during the call. If you do not wish to have your image recorded, please turn off your camera or participate by phone. If you speak during the call or use the video connection, you are presumed consenting to use your voice or image. If you have technical issues today, you may type them in the chat box and select to send to the host. We will be muting lines to minimize background noise.

Now, about today's workshop … pursuant to the Department of Energy Research Act of 2018, the Department of Energy established the Research Technology Investment Committee, or RTIC, to identify potential cross-cutting opportunities in basic and applied science and technology. The Energy Storage Grand Challenge is managed by this committee. Today, you will hear from Dr. Sharon Wood, Dean of Engineering at the University of Texas, Tom Pierpoint at Austin Energy, Diana Bauer from the Office of Energy Efficiency and Renewable Energy, and two outstanding panels about Energy Storage, Goals for 2030 and Technology Pathways. We also want to thank the National Laboratory who has been a keep partner in bringing this workshop to life and helping us transition to this virtual format.

To get us started today, our welcome comes from Dr. Sharon Wood, Dean of Engineering at the University of Texas.

Hello, everyone, thank you for joining us today, virtually. For the DOE grant storage challenge workshop. My name is Sharon Wood and I am Dean of the Cockrell school of engineering. We are pleased to host this event and we hope that you will find these conversations to be valuable. I want to think Alex long professor of electrical -- and the organizer of this event for inviting me to participate.

Obviously, I wish the circumstances were different and I could be welcoming you on campus in person. The COVID-19 situation has been extraordinarily challenging for all of us. Especially those researchers who have been forced to temporarily close labs and pause their experiments. I am confident that the research community will persevere. Thanks to virtual events like this that bring leaders and experts together, you're working to solve society's grand challenges and strengthen our energy future will continue moving forward.

I would like to take this opportunity to give you a few updates about the Cockrell school. Texas engineering has been a global leader in technology advancement and engineering education for over a century. The past few years have been particularly exciting for us. In the fall of 2017, we opened a transformative new engineering building. The engineering education and research center which has greatly enhanced our teaching and research abilities. This was the first building on our campus to be designed such that the architecture fostered multidisciplinary interactions. Normally this building is full of students and faculty who are sharing ideas and collaborating. It has truly transformed our engineering community.

Next summer, we will be opening the Gary Thomas engineering building. It will serve as a new hub for all kinds of energy research on the UT campus. These new facilities reflect our vision for the future of engineering and innovation. And help us strengthen our reputation as a leader in fields like power electronics and battery research. Reputation that has been established through the hard work and dedication of the extraordinary researchers on our faculty.

As many of you know, one of our faculty members, received the 2019 Nobel prize in chemistry for his work in delivering the lithium-ion battery. John has long been concerned about the impact of climate change and he has been working for decades to reduce the world's resilience on fossil fuels. At age 97 he is still active, actively pushing the boundaries of battery technology to develop safe and affordable alternatives for energy storage. He is an inspiration for our society and exemplifies the school's -- that will make a positive impact on society.

I am hopeful that today's discussions will reveal opportunities for collaboration that can propel new technologies and change the energy storage landscape for decades. The Cockrell school is pleased to be hosting these conversations and we are grateful for all of you for joining this virtual workshop. And Q. -- Thank you.

Diana, you are on mute still.

Okay, can you hear me now?

Yes, we can.

Excellent, thank you very much, it is my pleasure to be here to talk to all of you about the manufacturing and supply chain track for the Energy Storage Grand Challenge. So, the purpose for the manufacturing and supply chain track is to build and diversify a strong domestic manufacturing base, and also including integrated supply chains, and this is in support of U.S. Energy Storage leadership. It’s having a domestic manufacturing base can help us capture the benefits of energy storage technologies and we will economically benefit from having a robust manufacturing enterprise.

We are also, in order to do this, we need to rapidly integrate and scale innovations from discovery through to commercialization. And then another important aspect of the supply chain resilience is the reliable source of critical materials and components. In order to do this, we are focused on addressing major technical barriers in manufacturing energy storage, including for materials, components and systems … both to lower the cost and also to improve performance. And, sort of scaling up is also important as well as the critical materials supply chain integration.

So, in terms of the manufacturing supply chain, the Energy Storage Grand Challenge is focused on innovating here, making here, and deploying everywhere. Certainly, the manufacturing track is very focused on the make here and again addressing manufacturing scale-up, reduced cost, improved performance, and domestic supply chain resilience. Though we are focusing very much on make here, it is important to point out that innovation in manufacturing is not a linear process. There is a lot to back and forth between innovations and manufacturing as you increase the scale of production.

So, as we are improving our manufacturing capabilities, we will often go back to earlier stage TRL level innovation to get to the greater scale production. So keeping this kind of feedback, back and forth between the manufacturing as we scale it up and then the identification of barriers to be addressed, some of which through early-stage applied research is also important.

So, as I mentioned before, we are interested in integrated supply chains. That includes from raw materials through refined materials, component manufacturing, system configurations, system assembly, system manufacturing, used by the end-user and maybe there is another, maybe there is a secondary user. And then there is recycling, reuse and, hopefully, less disposal. So we are thinking about these, this full supply chain and we are also thinking about different research areas related to these different stages of the supply chain. For example, manufacturing process intensification; is there a way we can reduce the number of processes or the energy intensity of the processes by reducing the number of processes or making the flow from raw materials to end product more efficient.

As I mentioned before, critical materials processing and separations for membrane manufacturing. One of the ways to manufacture membranes is roll-to-roll manufacturing, so both of those give out different manufacturing processes as well as making membranes for the batteries is important.

In addition, if we are thinking thermal storage, new materials for harsh service environments, particularly high-temperature environments, is also important. We are thinking about a broad array of storage technologies, including lithium-based batteries, flow batteries, but also mechanical storage like compressed-air storage, pumped hydro, and chemical storage such as hydrogen, synthetic fuels and, as I mentioned before, thermal energy storage, including combined heat and power.

Back in March, we had a manufacturing webinar that was hosted by Argonne National Laboratory. As part of that webinar, we had a number of breakout sessions; examining electrochemical energy storage, flow batteries, chemical energy storage, thermal energy storage, and industries as storage—so flexible operations in manufacturing facilities and what the applications might be there. Through this March webinar, we do the breakout sessions, we identified some cross-cutting challenges, including manufacturing of membranes, bipolar plates, hybrid systems (systems that incorporate multiple storage technologies), grid integration technologies (how to get from a battery, for example, to storage systems, power electronics and other conversion technologies), raw material availability (potentially critical materials or other materials), and then finally, accelerating the translation of low-technology readiness level innovation to high-TRL prototypes.

So, in terms of, in the draft road map that we are preparing to release for comment, we have identified some technical barriers in manufacturing and specifically some challenges and then some actions that we are pursuing to address those challenges.

So, for addressing the technical barriers, the first challenge is lowering manufacturing costs for components including membranes, innards, cathodes, electrolyzers, other materials and containment structures. The second is reducing manufacturing barriers to improve performance. And so, these items are advanced materials, bipolar plates, heat exchangers, as well as other functional components of storage systems.

So, to help us prioritize where we are investing, we are pursuing a collection of technology assessment studies and then, also through the efforts of the Grand Challenge, we are working to integrate our investments across multiple offices so we can learn from one another in [pursuing the barriers] addressing the barriers and getting to improved performance. So, for the second action, accelerating manufacturing scale-up; the challenge here is that it is difficult to scale up and integrate emerging technologies, starting from the lab invention to prototype and then to commercialization. So, across multiple offices of DOE, we are focusing on scale-up actions addressing thermal storage, lithium-based batteries, and grid-scale deployment.

So, in addition, we are working to improve critical material supply chain resilience and, in particular, we’re focused on the fragmented supply chain for lithium and cobalt in batteries. To address this, we are pursuing the support of research and development on lithium processing and separations and also looking into batteries with reduced cobalt requirements, and finally, we are supporting a number of, we have a number of programs that are supporting innovations in battery recycling.

We also are in the process of developing a request for information that should come out in the coming weeks. This is a preview of questions that you can expect in this RFI. I would encourage you to stay tuned for the release of this and share your insight. Here are some of the types of questions that we anticipate asking.

We would like to know more about the pressing challenges for scale-up of the manufacturing of energy storage systems. And then, maybe there are some additional challenges to getting to and maintaining a strong, fully domestic supply chain for energy storage. And what additional materials or components might have large barriers to lowering the cost for energy storage systems. And then what methods, what manufacturing methods would have the greatest impact to improve the performance and/or lower the cost for energy storage technologies.

And finally, we are also interested in hearing your views on storage manufacturing and supply chain policies that would help establish and maintain manufacturing capacity within the U.S. And that is it. Think you very much.

Thanks Diana. And now to provide today’s keynote, please welcome Tom Pierpoint from Austin Energy.

Hi, this is Thomas Pierpoint, vice president of electric system engineering at Austin Energy. I would like to talk about energy storage at Austin Energy as part of the keynote workshop. For the U.S. Department of Energy Storage Grand Challenge. -- Is the greatest engineering achievement of the 20th century improving life for everyone. Modern society cannot function without electricity.

We wish to thank the many that serve this critical entered, industry and continue to improve and innovate. Many changes are exciting and it is also fantastic to be such, part of such a collaborative industry. Austin Entergy, the U.S. Department of Energy and our partners have worked closely to make advances in energy storage. We wish to share our story of where we have been so far, we look forward to further involvement as DOE works to advance the industry in this area.

I would like to start with background about Austin Energy. Public power founded in 1895. We are the eighth largest utility, community owned utility and second-largest in Texas. We report to the city manager who executes policy and directs the city Council. We have about 1500 employees and $1.48 billion in operating revenue. We serve the greater Austin area, 437 square Isles, miles of service area including the city of Austin and three surrounding counties. There are 485,000 customer accounts. We are a vertically integrated utility in a deregulated, wholesale market.

As of 2018 we had a system peak of 2900 megawatts and a winter peak of 2400 megawatts. Facts about our power delivery system. In our generation side, we have 4800 megawatts of generation. Simply owned, some partially owned and some under contract. We have two generating plants that we own Sand Hill generating plant and also Mueller. We have 624 miles of transmission lines, 74 substations, we have 2 power storage systems which we will talk about in a bit as part of the DOE SunShot and Shines projects. We have three central chilling stations that provide cold water for air conditioning. We have 485,000 customer accounts and survey population center of 2.2 million people. Two solar farms, 9000 solar generating customers and we have an active demand response and energy efficiency program.

We just updated our resource plan in March 2020. We have increasingly aggressive carbon reduction goals, we have changes in our generation portfolio as we meet those goals, we have utility scale storage, demand-side management and customer programs, we have utility managed electrical vehicle charging infrastructure, we are looking to increase our distributed generation programs. DER commit energy resource integration is for us and we have a grid monetization including transmission as well as AMI and analytics. Austin Energy was a major participant in the son shot and shines projects for DOE. In February of 2016 we see received the largest shines contracts inning grant valued at $4.3 million with 50% matching provided from Austin Energy. DOE had substantial involvement.

The goal of the Austin shines project is to establish a template for other regions while allowing to maximize penetration of distributed solar PV. The solution is intended to enable distribution utilities to litigate potential negative impacts of high penetration levels, that are caused by the variability of these. A little background on our two energy storage sites. The first one is the Mueller energy storage site. We also have a security wall that meets the strict local neighborhood design guidelines. We have a second installed in one of our substations and it is at the La Loma community solar system and the Kingsbury battery system.

 Each of these are 1.5 megawatts eats, each. Partnerships were the key to success with the Austin SHINES and DOE son shot projects.  Also involved was the city of Austin, the University of Texas, and a number of other vendors who were critical to the success of this effort. Austin Energy is continuing to build on the success of the DOE son shot and SHINES projects.  Austin Energy applauds the bold vision of the U.S. Department of energy, Energy Storage Grand Challenge. We appreciate the chance to share our story on where we have been and we look forward to further involvement as DOE continues to advance the industry.

Thank you so much to Dr. Wood, Diana Bauer, and Tom Pierpoint.

We have two outstanding panelists for you all today. Ralph Masiello of Quanta Technology will moderate our first panel on 2030 Goals and The Vision for Energy Storage, and Dr. Deepak Divan of Georgia Tech will moderate our second panel on Technology Pathways. We know that you have lots of questions for our panelists—you have already started to give us some—and we want to get through as many as possible today. As our panelists are presenting, we welcome you to submit questions in the chat box and send them to the host. Because we are going to hold questions until the end of each panel, we would like you to reference the speaker or the topic when you submit your questions; that way we can make sure we are able to go through as many as we can. Ralph, I am going to turn it over to you to introduce our panelists for panel one and to get us started.

Thank you, this is Ralph Masiello from Quanta Technology. We have five great panelists; on the first panel, which is to set the state with discussing what are our visions and goals for 2030: Mark Rothleder from the California ISO, Tom Oberbye from Texas A&M, Venkat Banunarayanan from National Rural Electric Cooperative Association, Efrain O’Neill from the University of Puerto Rico—and also I think Efrain is working with Sandia currently—and Bob Cummings from NERC.

Our format for the panel is we have agreed on four questions that we’ll present. If you could advance the slides, please, Diana. Four questions. The first question is, where do we think the grid should be in 2030? What is our vision for the electric infrastructure? Second, what kinds of boundary conditions—meaning limiting conditions, challenges, events, problems—could become more important over the next decade? Then, what is our vision for the role the energy storage simply? And the fourth, given we have defined where we want to be, where are we now and what has to be done to get there? Our format will pose one question. Each of the panelists will respond with a slide or two, and then we will discuss the next question.

Let’s move to the first question: What is your vision for the electric infrastructure in 2030? Aspects of this question that panelists will try to address variously, how do we accommodate the nation’s goals and particular state and city goals for higher renewables and adaptation to climate change? Second, resilience is a key issue for the Department of Energy and for Homeland Security—weather, earthquakes, cyber security, issues in physical security. And third, how do we accommodate all of the new technologies? The Internet of Things such as transactive energy. So, [Inaudible] Tom Overbye will be the first to respond to this question.

This is Thomas Overbye from Texas A&M. I hope our future is bright and my vision is that we can develop a truly resilient and sustainable electric infrastructure, both here and throughout the world. But my concern is that in pursuing this, we need to avoid thinking too narrowly about the future. We really do not know what is coming and that is something that the COVID-19 crisis has shown us. Hence, I think our research focus needs to consider a wide range of different future scenarios. A term that we used in a 2016 National Academies report on the electric grid was the need to future-proof the grid so that regardless of what comes, we are prepared. Here at Texas A&M, we are developing a quite advanced electric grid test environment that allows us to immerse people in a wide variety of future scenarios. These include scenarios with lots of storage and renewables, and ones under both normal and highly stressed conditions. I think we need to really be considering a wide variety of situations.

Thank you, Tom. Mark Rothleder is up next. And the California ISO, [Inaudible], is well down the path of facing some of these issues. Mark?

Thank you, Ralph. And thank you for the opportunity to discuss this topic. If you can move the slides ahead? Thank you. So, in California, we are well into the transformation, but still at the very early stages of the transformation to a clean energy grid. There are several aspects to what is happening in California; most notably, we have got the aggressive renewable energy goals, whereby, by 2030 we are expected to get to 60% clean renewables.

We have already achieved 33% effectively, about a year or two earlier than expected. By 2045, the target is really to be 100% clean energy by 2045. In addition, but in parallel to the renewable goals, is the specific greenhouse reduction goals over the entire energy sector, reducing GHD energy to 80% of 1990 levels. That may ultimately be the more challenging target as we achieve this transformation.

Other goals that are in effect, we have a 5 million vehicle energy goal by 2030; distributed generation by 2021 of 10,000 megawatts of distributed generation, of which 1.3 gigawatts of battery storage by 2024. Honestly, the 1.3 gigawatts of battery storage will probably be eclipsed ultimately by the fact that, with other policies in place, including the retirement of the remaining once-through cooled resources, was about 5,000 megawatts once-though cooled gas steam generation that would still be due to retire in the next few years. There is a pending shortfall that needs to be addressed of about 2,500 to 4,400 megawatts of capacity between now and 2023.

If you go to the next slide, to meet that shortfall, what we are finding is that much of the shortfall will probably be met by either new stand-alone storage, likely battery storage, or some combination of solar or renewable end storage. What this slide illustrates is the fact that there is plenty of, at least indication through our interconnection queue, that there is resources capacity that could be developed.

There is about 24,000 megawatts of storage capacity in the interconnection queue. A lot of that will not ultimately develop because it doesn’t get PPA or the interconnection process, but similar to what we saw in the solar situation where we saw this wave of interconnection requests come in and then the price dropped and the actual solar developed. This is an early indication that there is demand and capability of large amounts of storage to be developed. I will turn it back over to Ralph at this point.

Good, thanks, Mark. In 2008 when the energy advisory committee was working on the first storage report, if you had told us that there would be 20,000+ megawatts in the queue for 2030, it would have been seen as fantastic. Venkat, you are up next. 

Thanks, Ralph, and hello everyone. Thank you for the opportunity to be on the panel. The vision in terms of electric infrastructure, obviously as Tom and Mark had mentioned before, we are definitely looking at the grid, I think, looking at 2030, more agile, more resilient. And what also struck me is that 2030 isn’t that far away, it is less than 10 years away. That is a shorter timeframe, so we are talking about a quick transition. But we are also looking at the way the grid is evolving. We should be prepared for an increasingly asynchronous distributed generation and load, and what does that really mean in terms of grid planning and iteration? That is something that will grow more and more as we go along. So, that is something to be looked at.

The other thing from our member’s perspective, [Inaudible] electric cooperatives who are there, and mostly in rural areas, there is an increasing trend toward digitalization of grid access. When we talk about [Inaudible] planning and operations, the more digital access gives us more flexibility, more options and more data to make decisions less. Also, the trend we are seeing and I think we will continue to see is automation of grid operations. When we talk about, especially in rural areas again, the density of consumers per mile is much lower than other suburban or urban areas. Any savings and costs directly translates into reduction in rate, or lower rate increases, however you look at it. So, more automation involving a variety of technologies [Inaudible] are being employed, [Inaudible] and it’s going to increase. It certainly saves time and money and effort and increases safety. You will see more of that.

Then the other trend is data-driven decision-making. As we digitalize more and more grid access, we are getting a lot of data in and increasingly we are looking at how we can use data to understand the system better and make decisions better and use that data for advantageously in planning. And the trend that is taking off right now is the use of what I call data-driven technology. Such as augmented reality or robotics or others. We are trying those technologies out in use cases such as education and training, but also situational awareness [Inaudible] operations. So that is also increasing.

And of course underpinning it all is increased consumer involvement. The consumer members of our electric cooperatives and others are increasingly involved due to the variety of technology options that are available. That brings the need for [Inaudible] providing them more information and creating programs that are tailored to their needs. I think these are some of the trends that will increase as we move along toward 2030.

Great, thanks. Efrain O'Neill, please.

Hello, my name is Efrain O’Neill from the University of Puerto Rico, Mayagüez. I would like to acknowledge my co-author of the material [Inaudible], also a professor at the University of Puerto Rico Mayagüez. For over 20 years, [Inaudible] and I have been working on various aspects of our systems, specifically in island and remote communities in the context of Puerto Rico but also in the context of the Caribbean, especially the Dominican Republic, and also collaborations in the U.S. Virgin Islands.

Based on that experience, that has been funded by DOE, the National Science foundations, as well as local sources, we envision a more distributed power system in the Caribbean and also in other tropical islands around the globe, as well as in coastal and remote communities. We think there will be a widespread use of on-site renewable energy, not only because the resources available but also it yields local economic social and environmental benefits if properly pursued. We think that solar communities, which are communities that own and participate in the operation of their own solar systems, will be common in these communities as well as community microgrids. Of course, these options bring more resilience as well as more processing ability.

We also think that because most islands in the Caribbean are small islands and also many islands around the world, the geographic extension is small. Electric vehicles will also be a main resource that ties into the future of the electric infrastructure. And very important, we envision a trained workforce and informed citizenry, so all of these things that we envision for 2030 in island and remote communities can occur without local workforce. Citizens are informed of the options and limitations of these options for the future. Thank you.

Thanks. Bob, the last one on this question.

Good morning, thank you very much for the opportunity to address this body. My vision for the 2030 infrastructure has a few key components. They are not listed in any particular order. There will be a bulk power system because large cities like New York cannot self-sustain on renewables. There is just not enough service area for solar panels or places to put windfarms. Storage needs to be optimized for the use of renewables. I cannot see a point where we would not need lots and lots and lots of storage in order to take advantage of the variability and the extra energy that is going to be generated by the renewables that are on the plate right now. Not to mention what might be coming forward.

There are some cautionary tales. Fast-charging electrical vehicles, the distribution and transmission system today, it is not ready to support these large chargers. These very fast chargers are 100 kilowatts. They are the size of a small shopping center. If you put that on a small distribution system, it is not going to work very well. Similarly, the transmission system will have to be rethought and reengineered to support those. Microgrids hold a lot of promise but they are one-off designs. They do need to be predictable, the system does need to know what does this thing look like. Is it a generator? Is it a load? And that needs to be predictable for operations.

Distributed energy for local resiliency, storage near critical loads like medical, fire, sewage, water supply, that is proven to be in some of the DOE studies to be a really good way to go for having stand-alone distributive energy storage. We also need to be rethinking power supply to remote communities using microgrids. But one of the key things to success there will be modular system designs. So, if we have a hurricane come through Puerto Rico, we can fly in pallets of already designed components that can be put together quickly.

The overall grid will be more brittle as we lose synchronizing torque and inertia. Synchronizing torque essentially is the ability to keep generators rotating together as a whole as we do not have any rotating machines anymore, this system will tend to not want to stay together. Even some simple outages of today will get larger than they are today. That does it, back to you, Ralph.

Thanks, Bob. We all need to pick the pace up a little bit to keep the entire program on track.

The second question is, what kinds of boundary conditions do we need to worry about? Not only the traditional ones of contingencies, transient stability and the like, but aging infrastructure. Again, what the complexity of all these new distributed elements brings and how will our operations markets workforce have to adapt?

Venkat, you are first.

Yes, there are a few things in terms of boundary conditions. I will go through all of them in the interest of time. I just want to point out a couple of things. Cyber security, we all know about that. Workforce sufficiency, the [Inaudible] workforce is almost becoming an endangered species in terms of its availability, especially in field operations. As the [Inaudible] workforce is getting older and more people retire, how do we really fill that gap. That is very critical and automation will certainly help, but to some extent, we really need a solution, a sustainable solution. The third one, extended duration event. That is what we are going through right now in the pandemic.

The key thing there in my mind to think about is, [Inaudible] there has not been a major weather event. Another event coming in. What if there was? Like a hurricane or something? So how do we do that extended duration event? [Inaudible] destruction, how do we plan for it? And so that is going to be a boundary condition.

The next one is the dependency. I put on dependency and interdependencies separately because, for example, as we electrify more and more, [Inaudible] it is more efficient and cleaner, more things depend on electricity. A perfect example is broadband. Will have broadband Internet. Energy goes out so does the broadband. Interdependency, it is increasing because no longer are we dependent only on [Inaudible] or coal or gas, but we are also dependent increasingly on the sun shining and wind blowing and as the penetration of renewable increases, which of course speaks to energies of the road, but the interdependency needs to be realized first.

There has been enough talk of resilience. We need to think of resilience as a boundary condition and a [Inaudible] one and not just electricity but as a community, what do we really mean by resilience? The last one, just to repeat Bob’s point earlier, inertia at this point in time is going to be varying much more throughout the day than it was before. As we get more asynchronous with [Inaudible] generation and load, we will get very low inertia in the mid-afternoons [Inaudible]. So how do we plan operate the grid? I think analysis is needed to understand the behavior of a grid under loadbearing inertia?

Mark?  

Some of the boundary conditions that I am seeing occurring as we transform the grid, we are seeing daily needs for flexibility both magnitude and basically frequency to cover that variability in the evening ramp can visualize a [Inaudible] curve. That is increasing and becoming a boundary condition. I think in the future as we get more and more renewables, we also have to consider the multi-day events. When weather conditions are such that you do not have solar production or you have relatively low solar production, low wind production for multiple days, that I think leads to potentially different solutions in terms of the types of storage you need versus daily use of storage. I think that’s a boundary condition.

Generally speaking, as we move away from the rotating mass, the gas resources, the traditional resources, we have got to find and ensure that sufficient capabilities exist in the new fleet of capability, whether it is using the renewables or getting this new capability in terms of reserves, frequency response, or looking to other devices, including storage to provide the capability. It has been touched upon before, but reliability and resilience is certainly a boundary condition. I think it becomes even more complex as the environmental conditions change.

As you are all aware in California, we have now public safety power shutoffs when there is risks to the system because of wildfires. I think that leads to and may increase the pace of potential solutions to address some of those communities affected by those local shutoffs. Microgrids then become part of the solution. One of the other boundary conditions as we get more and more of these new technologies is, how do we optimize them? Our optimization techniques have been developed in the context of the types of resources we have. Conventional resources that are responsive when needed, yes you have to manage the fuel supply, but the fuel supply is generally not a limiting factor.

When you are dealing with limited duration storage, where you are trying to optimize how to use a 2 to 4 hour battery over the day and use it just right in context with the other variability, I think we need new optimization techniques to do that the best way to make sure that we are using these resources in the best manner we can. I think the other thing that is going on overlaying on this is that there is increase in the amounts of regional collaboration and coordination. I think that leads to the opportunity that you do not have to necessarily put the storage resources in the exact location, you can leverage the broader region and maybe put storage resources where they are best situated in the grid and then use regional collaboration to get the energy to locations.

That being said, you also have local areas where you need to meet certain local conditions and that may lend itself to having some very localized resources, as well. A mix and a diverse sort of resources may ultimately be needed. I will turn it back over to the next speaker.

Efrain O'Neill, please. Yes, boundary conditions in the Caribbean, very important as you have noticed, my comments will be focused on the Caribbean, one of the main messages I want to get across is, after a disaster in the Caribbean context, each community relies on itself. So this was a lesson very hard learned in Puerto Rico and other places after hurricanes. More recently, Puerto Rico has been suffering of a very active fault in the southern area of Puerto Rico. So earthquakes are a concern as well.

This is common in the whole Caribbean because we have the Caribbean plate and North American plate colliding basically, close to all the Caribbean islands. So any future storage solution must look into that. Also, climate in the Caribbean, humid, hot, corrosive, some islands there are drought conditions, as well. So there are some limits to the possibility of water reservoir storage, and of course strong or extreme winds. Something that is common also in the Caribbean is the electric infrastructure in general is in many places, dated. It is a conventional fossil-based and in many cases, oil-based, which is terrible.

We are already low energy power systems. Never mind integrating power electronics-based renewable energy. We are small system so our inertia is all by design because we are all small systems. I want to finish my comments with emphasizing that the context and solutions in the Caribbean and other island contexts are different from continental locations. So that is so important because many times, for example, after Maria, Puerto Rico got an influx of a lots of people wanting to help, trying to help, but not understanding the local context.

Sometimes, some of the solutions and some of the strategies really did not help and in some cases, were obstacles really to actually dealing with the problems we had and hand which were uncommunicated areas, areas that could not be reached in days and even weeks. It is very important that any solutions and any strategies going forward when thinking about the Caribbean deals with the local context and actually engages with the local communities and the people that have been working in local problems that understand the limitations and possibilities that are available in the area.

Bob?

Yes, I’m not going to read all the words on the slide because there are a lot of them. I think there are three areas of concern here or things we need to solve.

Daily use: Security-constrained dispatch down to the feeder levels is a new concept for the industry and for the populus. Multi-layer dispatch is going to be necessary. Also problems with conflicts in the interaction of controls systems can result in a yet to be seen oscillatory system behavior; this can be rather damaging.

To accommodate 100% renewables, we need to rethink the power supply from the bottom up and integrating things in a smart grid and also being smart. So you have storage together with other technologies that work together. Sufficient reserves must be built in because and system resources need to be monitored. The ability, as Mark said, the ability to do ride-through multi-day storage needs will be essential.

On the resiliency side, the location of storage systems next to critical loads will be very helpful. And storage systems have to be adaptive and able to change their charge / discharge strategies. Sometimes on the fly. For recovery, fly-in emergency power supplies, fuel supplies, communications equipment, standardized connections mechanisms, those things need to be very helpful. And the lack of spare parts on-site at some of these locations, and knowledge about how to rebuild after, these things have to be addressed. These are coming forward. Thank you.

Good. Tom? Do you want to wrap up this question for us and we will move on?

Yeah, for me, a boundary condition I see is the growing complexity of the grid in a lot of different ways. I see it as an educator and I see it in talking to engineers who are out there on the front lines. For example, in doing dynamic situations, which I'm quite involved in, the number of models we have to simulate is just growing at an unbelievable rate and then you couple all sorts of additional control actions on this such as remedial action and it gets very complex.

We are also seeing more complexities in the grid as he gets coupled to other infrastructures, potentially such as transportation. I do wonder if the grid is getting so complex that nobody truly understands what is going on wholly and we are setting ourselves up for major problems, and, we all think someone else understands it. For example, determining and mitigating potential hidden failures is a real challenge. I think we need to bring in colleagues from other disciplines like human factors and have the right funding mechanisms available so these people can have a long-term commitment to become conversant in the electric grid. It takes a really long time to develop this truly effective, interdisciplinary collaboration moving forward.

Thank you, Tom. Let's move on to provisions for energy storage and very quickly, with every other commodity we take storage for granted. And, the Wall Street Journal reports on how much corn we have in storage, or how much wheat or pork bellies, or natural gas. Electricity is unique right now. But, my vision is it is another commodity, storage is cheap, routine, and we worry about how much we have stored, not how much storage we have. So, the first panelist on this is Efrain, please.

Yes, if I could have my slide. Some of the things that are in my slide were already said by other panelists and I will not get into the details [Inaudible]. Storage is definitely great for control. The more storage the better, of course. Control and energy management. In the Caribbean context itself, community microgrids, if the division that I presented earlier is to be realized at some level, you definitely need storage to realize that the community micro[Inaudible], and of course in terms of the ability that the Caribbean has to earthquakes and hurricanes, emergency energy hubs, small systems that provide minimal, critical services, not only to the usual critical loads like hospitals and emergency service management, but also to remote communities.

You have people that are required two refrigerate medicine like insulin and baby food, you could have resiliency hubs or emergency hubs deployed in strategic areas around small islands, remote areas, and storage would definitely play a part there.

My last comment is this is not something to look for in terms of 2030. In most of the islands, the electricity cost is expensive enough to make some storage space possibilities a reality right now if you had access to the capital to fund the expense. In Puerto Rico, the residential cost of electricity is around $.20 a kilowatt hour. And basically, a word that my colleague [Inaudible] has done with actual [Inaudible] with equipment placed in Puerto Rico, have storage and [Inaudible] systems at high priority right now. So, storage is a game changer right now, not just in the future. Thank you.

Bob, please.

There are a couple of things in my vision for the role that energy storage plays. Part of it will be nontraditional. You will find yourself charging batteries or charging in the middle of the day, which is nontraditional method, usually you charge at night from your coal and nuclear facilities. In a cold location with renewable loads, it can help avoid duplicative transmission infrastructure. High ramp rates will be needed for morning and evening with net load ramps as [Inaudible]. And, storage will provide an awful lot of the load following, the load-balancing, frequency control, frequency response and voltage support.

One of the things we have to get away from is the assumption we can take every bit of solar energy or wind energy, as it is generated, that simply is not the case. Storage is the only thing that can help us stop, that can change that. But storage will be a key part of the distributive entity research management systems as a very versatile tool. But, it'll have to be dispatchable to match demand. Modularization where it can be done is very important. But, the immediate need for utility-scale storage to meet the needs of the Duck Curve ramps, things that can’t be ignored as storage, and that is things like advanced pump storage systems that can ramp at 20 megawatts a second. Those are the things that need to be put forward. Thank you.

OK, Venkat, please.

Yes, the energy source [Inaudible]

Excuse me, we are having a hard time hearing you. You can adjust your microphone or how your speaking into the phone.

Okay, is this better now?

You sound very far away. [Inaudible] [ Silence ] [Inaudible] 

 [Indiscernible] 

 [Indiscernible]

 Mark?

 So, I think we are getting the idea here. Storage will have a role in all aspects of grid operation and planning, whether it be from transmission or resource adequacy. And resource adequacy can mean local system level, meaning peak needs or meeting the flexibility needs of the system. Or, daily or intra-hourly, very fine frequency control. It will play a role there. It will play a role in distribution management and load management for the customer end.

I think the real challenge is going to be knowing that storage is going to play a role in all aspects of the grid and how do you manage the storage when it has multiple use cases and potentially multiple masters of what is controlling that and what the objective is of controlling that storage device. That is a real challenge in the vision of the future. That will be how it is orchestrated over the multiple use cases of the storage.

Tom?

Yeah, storage can play a positive role. However, we need to know that the grid has to continue to operate under a wide variety of conditions, including the outliers. It is not adding storage to the existing grid but it is how well the grid operates as we start to depend on storage during extreme conditions. For example, what if a heavy wind- and solar-powered grid with storage were operating during a time period where might be cloudy for most of the month for a good chunk of the country? Living in central Illinois, I recall one December when we didn't get much sun all month. What if the wind doesn't blow? Also, as electricity becomes the primary fuel for other infrastructures, like transportation, and suddenly you are depending on electricity being there to charge your electric car so you can go somewhere and the electricity isn't there, it will compound the rest.

The future could be very bright, we have to set up the scenarios that effectively [Indiscernible] sorts of different conditions and study them and simulate them beforehand. Thank you.

Thank you. Let's try to get through the last question quickly. If each panelist would pick one of your votes as a headline to emphasize. We have five topics, subtopics and five panelists should work. Mark, you're up first with the obvious focus, I think.

I think I mentioned it. The gap that needs to be addressed is with the large influx of potential and use cases of the storage is how do we optimize or change our optimization techniques to ensure we are managing and harmonizing the use of the storage over all the use cases. Is not just the use cases, you have the diversity of the types of technologies that are available and they have different capabilities.

You'll have to delicately and appropriately manage those different, limited capabilities of the storage for the appropriate use of what you're trying to do. And again, you're trying to do multiple things, whether it is for the grid, or for load management or whatever you've got in terms of multiple day events, managing that storage will be, in my mind, one of the biggest challenges in the gaps we have to overcome, and it is different from how we operate the grid today. Thank you.

Tom, perhaps you could comment on the issues around the analytics?

Yeah. Our challenge with this grid, [Inaudible] making it more complex and trying to effectively keep the humans in the loop in doing this, coming out of the research community, I'm researched-focus. A lot of our research [Inaudible] on these complex systems. We need more research focuses on large-scale systems while working on real grid [Indiscernible] because of the CII concerns and the use of synthetic grids such as those being developed by [Inaudible] can a great alternative. And that will be the case as we look at integration of storage.

Venkat?

Just one, the infrastructure needs for optimizing energy inventories, [Inaudible] when we go into integrated energy storage for the rest of system, we need to tackle different control systems [Inaudible], if the storage is within a microcredit, it is a microcredit-control [Inaudible] control system. How do they all work together, how does data and control flow? And what is the impact upon the energy storage operations? The second are associated, additional costs which is tough to budget for. It is an impact both on costs and operations and obviously on expectations of performance. That is a gap, in terms of looking at energy storage in a holistic fashion, for the complete infrastructure that is needed and understanding opportunities and limitations.

Thank you. Efrain.

The one point I want to emphasize that touches on the bullets up there is that in the Caribbean context, looking at the gaps between now and the vision of 2030, especially focused on storage, you need to pay attention to context. Whatever solutions, regulatory models, business models and financing models must make sense in the Caribbean context. And within the Caribbean, your local contexts as well. It is very important that, not only that you look at the technology challenges and the technology solutions, you need to factor in the human factor.

You need to get down to the community level and look at what the perceptions of the people are, what the real needs are. It is a two-way street. As engineers and technology [Inaudible], we can share the limitations so we can address some of the misconceptions that are out there regarding the electric grid. So, that's the point I really want to get across in the Caribbean context, you need to pay attention to context and solutions and the problems and needs are different from the continental solutions and other mainland technology ideas. Thank you.

Thank you. Bob? Last comment.

Yeah, I think the overarching thing that we need most is this development of cohesive system control and dispatch algorithms across both transmission and distribution. We need aggregation of resources and a thing called the distributed energy resource management system that can bridge all those gaps. And how do you make these things harmonize together? That is the key thing that has to be developed and is starting to be developed now. Thank you. Thank you.

I think ICF is going to organize the questions for us.

Thank you so much to all of our panelists. It was a great discussion. We had a number of questions come in. I will start first with Mark or Bob here.

To what extent is it important to push for 24/7 coincident renewable power using energy storage?

This is Mark. I think it is a byproduct of the fact you are trying to reshape resources that are produced when the fuel supply is available, be it solar or wind, and you're trying to meet a demand curve that is differently shaped from the natural generation patterns. And, the way you can do that is to reshape, store the energy when you have a surplus of energy, in the middle of the day like we do in California sometimes. And store that and produce when you have the need for the energy, thus the evening peak, when you don't have that supply and it is gone down and you don't have wind.

The storage is a key in reshaping that supply that is no longer controllable but it is a variable supply to the needs of your demand. And, I think that is how you get your 24/7, if you want to say coincident renewable, it is not the renewables are producing exactly as is needed but you are reshaping it with the storage.

Very good. Our next question is for Venpak or Efrain. 

To what extent is the organization examining how energy storage can support [Inaudible] fossil needs?

Yeah. [Indiscernible]  [Indiscernible] 

Very quickly, this is Efrain, this question poses an important challenge. We talked about vision and gaps. We didn't talk much about how we get there. Of course, there will be a transition period and this goes to my comment in terms of the Caribbean. There will be a transition period between a fossil-based, fossil-dominated power systems in the Caribbean to a more hybrid system where you have both rotating machines, also operating with renewable-based infrastructure.

One of the key questions is how will that transition take place? That is why it is so important to look at, and I emphasize the context, the challenges will be different during the transition. There will be a transition and fossil-based units and/or conventional units will coexist with renewable-based and storage will be a key asset in that process. Thank you.

Thank you. Tom, this next one is for you.

What is your response on how fast storage needs to respond? For example, [Inaudible] can respond in milliseconds. Is that desired by the grid?

The answer to that, it depends. I think the batteries can respond fast enough and like Bob, I'm a big proponent of the inertia provided by synchronous machines. I do think that we can use synthetic inertia coming off the storage to replace some of that inertia. I'm not too concerned about how fast the storage can respond. I think we will get there.

The concern is that, one is the increased complexity because it would be more of an active control and, then the concern about if we start depending upon storage, the next question is what happens when the storage runs out?

This is Bob. I think Tom hit on it pretty well. This thing we call synthetic inertia really is high-speed energy injection, and what its purposes is to offset the result of lost lower inertia which is a high rate of change in frequency during the frequency of event. We want to act fast but it will probably need to be on a non-step proportional response on a [Inaudible] characteristic. Otherwise, you may end up in a situation where you could destabilize the system if you move too fast.

So, we really have to look at that on a fairly locational basis. Remember, the system itself, nature doesn't jump. It doesn't need happen in milliseconds. Thank you.

Bob, the next question, you may have answered it here.

How important is inertia in an energy storage technology?

I think I answer that in the last one.

Okay. So, Mark?

What role does water scarcity and drought play in California ISO’s consideration of energy storage technology?

I think it is important as climate change and your susceptibility to water scarcity emphasizes that you may need another element, not just storage meeting multi-day events but also seasonal events and even multiyear events whereby you want to ensure you have a secure supply of capacity energy and reliance on your existing hydro resources.

Even in dry hydro years, hydro systems are generally able to provide you some peeking capacity but doesn't have the energy to meet your energy needs over the entire year. You need other resources, other capabilities in recognition of that susceptibility to drought conditions. Thank you.

Mark, one another one for you.

What level of demand-side participation in generation storage is available to commercial, industrial and residential customers?

I'm probably not the expert on this but increasingly we are seeing storage play a role where commercial, industrial and residential customers are using those, are integrating storage into their energy systems behind the meter to manage their demand-side charges, to manage their security. I think the real question there is does that influx of storage that is at the commercial, behind the meter, use, does that then reduce the ability for the capability to be used by the grid? That would be a lost opportunity if there wasn't this large amount of storage in the industrial, commercial and residential energy systems that wasn't also available for some kind of optimized use for grid use.

Thank you.

And I think our last question we going to be able to give this panel, [Inaudible] has anyone developed an energy storage profile? This would be used to determine how much long-duration storage, how much several minutes of storage the system needs.

I will respond to that from the island perspective at the University of Puerto Rico, Mayagüez. We have mainly done studies at community levels and a typical profile in terms of storage, for a typical household in Puerto Rico would be 10 kWh. That gives you a rough idea of the storage needs. However, that is not only storage. Storage is not a silver bullet. It has to be tied up with demand size, management, demand response, how much sun did you have that day?

So, storage is part of a larger strategy. And from the residential perspective, and in the Puerto Rico and Caribbean, 10 kWh was the rough number we estimated.

The [Inaudible] this is endeavoring to develop the storage profiles for large-scale systems operating over the course of a year to test out different scenarios. We haven't finished it yet.

Thank you for the wonderful questions, answers, [Inaudible]great panel. It is time for our second panel to come online. I am pleased to introduce Dr. Deepak Divan from Georgia Tech who is going to moderate our second panel, Technology Pathways.

As a reminder to our audience, please continue to submit your questions to our chat using either the speaker’s name or the topic. Deepak, I will hand over to you along with controls.

Thank you. Okay. Good afternoon and good morning everybody. I'm pleased to be moderating these panelists. We have fantastic panelist on this panel on Technology Pathways. I am presently at Georgia Tech as a professor and director [Inaudible] of distributed energy. I've been working in the space for a long time. I have a number of start-ups [Inaudible] academia as well. The other panelists, let me introduce them. Cliff Ho from Sandia National Labs, he is fellow of the American Society of Mechanical Engineers and is a senior scientist at Sandia and works on solar energy and energy storage. We also have Sanjoy Banerjee. He is a distinguished professor from the City University of New York and is executive chairman of Urban Electric Power which is a spin off that manufactures batteries for grid applications.

We also have Professor Alex Huang from the University of Texas at Austin. He is working in balance systems, mainly power electronics. Is a member of the National Academy of Inventors and has done some start-ups in here as well. We also have Professor Paul Albertus from the University of Maryland. He works in the area of energy storage.

Has also served as program director at [Indiscernible] for the $30 million [Inaudible] program [Inaudible] storage. And finally, we have Frank Jacob from Black & Veatch and he has really been focusing on duration for storage and will give us a perspective on what is imminent.

You can see, we have a fantastic panel. I want to take a minute to set the stage for what we will talk about. The panel has talked at length about the applications of storage, the grids and the concerns and the issues that come up as we start integrating more storage onto the grid. There is no question in my mind that energy storage is really here to stay already and is the key to a stable future. We see a significant number of applications built around mobile, that is where a lot of the advances have occurred. Whether EVs, trucks or buses or semis, we're starting to see that.

We are starting to see around 60% year-over-year growth. Even the most pessimistic projections in the last two years have turned into significant estimates in terms of [Indiscernible] which is driven by the low cost of batteries. We are already seeing signs that the $100 kWh is being beaten in the market, way ahead of schedule, all very positive.

On the other side, you look at the grid and you see that integration [Inaudible] PV with energy storage is occurring already as we speak. A number of speakers from the previous panel that have mentioned that. And we are seeing in [Inaudible] storage, which makes the resource dispatchable, hey are already beginning to see grid parity in many areas. We had a discussion on Puerto Rico and resiliency, California [Inaudible] presented, so resiliency is extremely important. And short duration resiliency that comes from within the community, they will frequently have storage as a big part of it. We have seen [Inaudible] on the grid, we had a discussion of among the utilization.

You can have a 100 megawatt plant go from a contract to operational in 60 days, that is absolutely amazing. And for long duration, we are starting to seeing applications of hydrogen [Indiscernible] has been very big. In terms of stationary applications, I want to make sure we see that there are two different applications. One is called dynamic rebalancing, this is real-time rebalancing. Many people talk about the California Duck Curve as an example. This could be non-storage resources [Indiscernible] or it could be storage as hydro.

But I think the biggest application for storage is this process of time-shifted generation which can be minutes, hours, days or seasons. There’s a very wide range of topics to cover and DOE has been involved in these. It is a complex process of taking technologies all the way to market. And, the approach that DOE has been using to look at that is looking at the level of integration from a technology point of view and increasing market-readiness. If you plot what various DOE labs are doing in various storage areas, you can see it covers the entire quadrant out here, from one end to the other. And, this includes everything from back-testing to basic materials to power electronics to field demonstrations, and then helping to commercialize this as well.  Look at the way the matrix moves, goes from the left corner to write corer and the process, itself, has all the various elements associated with what needs to be done.

With that framing, I want to turn the conversation over to the first panelist which is Sanjoy Banerjee [Indiscernible], [Indiscernible] questions and answers. Thanks, Sanjoy, go for it.

Thank you. Good afternoon from New York where the weather is wonderful for once. But, we are all indoors mainly. Anyways, let me talk about electrochemical energy storage, mainly batteries. The first slide I show you shows the current realities of how much global batteries sales there are, about $20 billion each, in terms of lead acid, $20 billion lead acid, $20 billion, roughly lithium-ion, about $13 billion in zinc manganese dioxide primary batteries, and a small amount, maybe about a billion and a half [dollars], in other technologies.

This sets the stage and context for what manufacturing capability there is and what we might expect to happen in the next decade. I will move on to the next slide, which shows you the energy storage capacity of the materials that are involved in these batteries. I'm comparing with Niagara Falls which is about 60,000 MW hours per day and that energy, theoretically, could be stored in about an 18 metal cube, zinc metal chunk, which would cost about $93 million. It could also be stored in lithium, about $370 million and lead which is about $230 million, in rough terms.

to store energy and that is why they are in the basis of the batteries that have been widely deployed. The other thing you should realize here is that potentially, these metals could also store energy on a seasonal basis. Now, going back to where the plants and manufacturing are, in the next slides, I'm going to be quick, I show you the U.S. capabilities. You can see that lithium-ion is mainly produced here which is the yellow dot. It is a large plant, it is the Tesla plant. There are a number of smaller gigawatt hour-sized facilities which are lead acid plants, distributed over the country. A number of zinc manganese dioxide primary plants, which only give you one cycle but at a low cost, that are distributed on the east side.

The state of the technology is well-developed in terms of supply chain, both for the lead acid and the zinc manganese dioxide. For with lithium-ion, there are issues we talked about earlier. The costs are coming down rapidly. The thing to notice is the zinc manganese primary batteries cost about $5 a kilowatt hour. If these could be made rechargeable, perhaps at a slightly higher cost, there would be a great incentive to do this because there's already an existing supply chain and it is also very economical.

With that, I will stay within the box of five minutes. I want to move to the last slide which is shown here. And here I show the timescales for various potential developments. On the left hand, we have relatively incremental developments which could be potentially funded from private sources and these would, of course, be things which are improvements, lithium-ion, lead acid and so on.

But it is the intermediate scale that is of interest to the Grand Challenge, which also addresses many of the use cases that are of interest. That would require development, in particular, on the lithium-ion side, perhaps solid electrolytes, high silicon anodes, materials with low cobalt in the cathodes. The zinc manganese technologies go from primaries to high-cycle rechargeable systems, but using much of the same manufacturing capabilities. Perhaps going to high voltages with aqueous [Indiscernible] using recently discovered high-voltage electrolytes or dual-gelled electrolytes which are now being discovered, various manufacturing techniques such as additive manufacturing and so on. I would say lead acid, advanced lead acid, lead carbon systems could be in this intermediate timescale.

Related to this, there are technology barriers and I think these have to do a lot with the separators, some of these have to do with moving from intercalation to conversion reactions. This gives you more capacity and there are certain technical problems like dendrite controls and so on and you go on to metallic anodes. The risk are significant and I think, public-private partnerships would benefit the advance of this technology rapidly. And, I think this would be the area that one would focus on, the Grand Challenge.

There are, of course, disruptive technologies that they are on a longer track scale and I will not go into this. With this very brief introduction, I want to thank you very much and I will and that and had the controls to you. I'm done.

Thank you so much, Sanjoy, we really appreciate that. We'll go to Cliff Ho from Sandia National Laboratories. Cliff?

 Thank you. Good morning everyone from Albuquerque. My name is Cliff Ho, I work at Sandia National Laboratories in the Concentrating Solar and Renewable Energy Technologies group. I will give you an overview of thermal energy storage. It is important to recognize and acknowledge that there are non-battery options for large-capacity and potentially long-duration storage, and thermal energy storage is one of those options.

There are three primary types of thermal energy storage. The first being sensible or single-phase storage where use a temperature difference to store the heat. And this can be done by heating up liquids such as molten salts or solids such as graphite, concrete or particles. On the right, the images show building-size tanks that store molten salt for a concentrating solar power plant that I’ll describe in an example later, and down below is an emergent technology storing heat in solids such as particles to provide higher temperatures from power cycles.

The second type of thermal energy storage is phase change using the large, latent heat of fusion or evaporation to store energy, either in salts or metallic alloys. And, the third primary type of thermal energy storage is thermochemical storage. This converts thermal energy into chemical bonds. The advantage here is that you can store that energy, perhaps indefinitely, with little degradation for long-duration storage.

I will go over examples of each of these three thermal storage technologies. Starting with sensible energy storage, there are commercial, concentrating solar power plants that use lots of [Indiscernible] to concentrate the light to heat up a liquid, typically molten salt, to high temperatures, 400 to 600 degree Celsius. That hot liquid can be stored for many hours, and when it is needed, it is pumped to a heat exchanger to boil water, generate steam and spin a turbine generator for electricity production.

The one on the top illustrated is Crescent Dunes in Nevada. It is a 100 megawatt plant with 10 hours of storage which is one gigawatt total. The image on the bottom is from Solana in Arizona, a 280 megawatt [Indiscernible] plant with 6 hours of storage, so a total of 1.7 GWh of storage.

It is important to note the magnitude of each of these plants, we are talking over gigawatt hour compared to many of the large-scale battery deployments which have in the order of 10-100 megawatt hours, we are talking 1 or maybe 2 orders of magnitude larger storage capacity with thermal air.

The second application is latent energy storage. I'm not aware of any commercial latent thermal storage plants. There is a company called Highview Power that has developed and demonstrated pilot plants on liquid air energy storage and they are planning of facility in Vermont, a 50 MW plant with 8 hours of storage, so 400 MWh.

The principal is they use electricity during off-peak hours to compress air into a liquid using a [Indiscernible] cycle at very low temperatures. The liquid nitrogen is then stored at low temperatures in large tanks. When it is needed, the liquid is allowed to expand through a turbine to spin a generator for electricity production.

And the final example is with thermal chemical. DOE has sponsored a number of projects looking at using high-temperature heat to drive a chemical process to generate hydrogen. For example, in the reduction oxidation process using ceria where you heat up the ceria at high temperatures to over 1000 degrees C to reduce them, you then pass steam through the reduced ceria to oxidize it, the ceria strips the oxygen from this steam, leaving you with hydrogen, and the hydrogen can be stored and used in fuel cycles for electricity production or you can combust it to spin a turbine in a generator for electricity.

My last slide talks about the summary of these three thermal storage technology areas. With regard to sensible, this is using a temperature difference, storing the heat as a temperature difference in liquids or solids. The advantages are to mature technology, there are commercial applications in concentrating solar power with demonstrated large capacity on the order of gigawatt hours of storage for a single plant with low-cost storage materials. The challenges are you have heat loss and large volumes are required.

For latent energy storage, using a phase-change, going from a solid to a liquid or an example I gave, liquid to air, air to liquid. It has the potential for large energy density and there are some applications with liquid air and molten silicon that have been commercialized using latent plus sensible energy storage. The challenges are a relatively low maturity, there's also heat loss. And the air and silicon applications, they require extreme temperatures.

For thermochemical storage, this is storing energy in chemical bonds. The advantages they can have a large energy density, the potential long-duration storage in these chemical bonds. The challenges are relative low maturity, high cost and issues with material durability and kinetics. With that, I will turn it back over to Deepak.

Thank you so much.  The next is Alex Huang. Alex will talk about systems for electronics and things. Alex, you have it.

Thank you Mr. Deepak. Good morning and good afternoon. I'm here to talk about the importance of power electronics and how power electronics can help the deployment and the cost reduction of energy storage systems. As the first panel talked about the [Indiscernible] 2030 vision or the future of 2040 vision. There is a large penetration of [Indiscernible] energy storage. It will inevitably change the power electronics. It will play a great role in our future energy systems. Particularly, the electric grid.

According to DOE, 80% of the electricity in 2030 will go into some form of power electronics processing. It is quite important to talk about this. Today, I will focus on how we can help reduce the cost of energy storage systems as we look at the issue and value of the energy storage well-understood, how do we deploy this in large-scale, and [Indiscernible] in our energy system is the key. This is an example of the cost reduction of battery package. This material cost and fabrication costs, in this example is automotive of battery pack [Indiscernible]. It has a major impact on cost reduction. So, we are working the solar aspects, the solar panel cost reduction goes to a similar roadmap of cost reduction.

As the costs are reduced on the battery, the balance of the system cost, the percentage of the balance of the system cost increases. This has been true in the solar industry and will also be true in the battery industry and the energy storage industry. And in this case, the electrochemical energy storage. Here is an example of the percentage of the cost [Indiscernible] of the electrical system, structural installation costs and tax, and many of the soft costs associated with battery systems on the right-hand side. This percentage is essentially different, where you have the higher power cost similar duration of the energy sources.

The balance of the energy costs have become higher and higher. What can we do to reduce this? And power electronics can play a major role. I'm using this graphic to illustrate the role power electronics and how they can potentially impact this cost reduction roadmap. For example, in the world of electrochemical batteries, we have a cell voltage around 3.7, [Indiscernible] example [Indiscernible] the end application we have voltage from 240 V in residential to several hundred volts in UPS applications to 480 V using industrial applications to tens of thousands of volts for grid applications.

Considering the big gap in the technology, what are the two [Indiscernible] of technology we use to address this issue, in the battery level, we devote [Indiscernible] then we need battery management systems to manage the batteries in the system.  This is part of the balance between costs in a battery system. Then we need to change the DC to AC or turn the DC into different voltage, that is where the power electronics comes in to bridge this American version requirement. If we need more voltage, we have another technology called a transformer where we can step up the voltage to a higher voltage. This is what we do today. In the future, we can use power electronics to increase the level of integration.

For example, we can use power electronics to lower the voltage to be closer to the battery technology, on this, this can generate higher and higher voltage so we can connect to our medium-system grid for a large-scale energy system. From a functionality point of view, power electronics can control the power flow, the reactive power and many things we discussed in terms of [Indiscernible].

few examples is, I will show how we are doing this. For example, one of the key technologies in power electronics is now we can move from [Indiscernible] silicon technology to provide much better type of power electronics, power processing capabilities at high frequencies. With this, for example, if you bring solar and batteries together and generate a medium-voltage output to address [Indiscernible] multi-function and through generated medium-voltage output, this is one way to do it.

Another way we can do it is lower the [Indiscernible] voltage to close to the battery so you can reduce the cost of the battery management system. We can look at the topology and architecture innovation so the battery and power electronics can directly connect to the soft transmission system at 100s of megawatt level. These are examples of how our electronics work and help our electronics can play a bigger role in developing next-generation controls, such as inertial controls that was talked about in the previous panel.

To give an example, [Indiscernible] low inertia system issue. And finally, my recommendation is we need to emphasize system cost reduction in the future and invest in the types of integrations between various technologies across the supply chain. I think I'm running out of my time. I will hand it over to Deepak.

Thank you, Alex.  Next we will hear from Paul Albertus from the University of Maryland. Paul, thank you.

 In morning, good afternoon. Thank you for the invitation and introduction. I will be speaking today about long-duration electricity storage. The vast majority of storage projects today are for less than 10 hours, 8 is referred to as long-duration. What can you do with a storage duration of say 10 to 100 hours? It is similar to what you can do with an 8 hour project, but you then can obtain days up to a week or so of duration. So, for load customers, this could be extended backup generation, for delivery customers, it could be extended duration for transmission and distribution, a deferral of load pockets.

For generation customers, it could be things like generation smoothing over timescales of days or perhaps a week. Or, for the output of individual winter-solar installations over much longer durations. That has some benefits, it is not how to understand how having long durations could be beneficial, but the real question is whether it can be done economically? Are the technologies that can [Indiscernible] cost pools.

As Deepak mentioned earlier, I lent creation as a [Indiscernible] at ARPA-E, the Days Program which focuses on storage that last for days. This is underway and active. Just to have a granular look at one of those particular use cases. Let's look at long-duration storage on a large grid. This is a figure that shows the maximum required storage duration to meet the hours of load over a period of years or decades versus a fraction of variable generation on that grid, for example winter-solar.

Within many tenths of a percent, depending on the amount of curtailment, transmission, and grid flexibility you have, intraday storage, within a single-day storage [Indiscernible] should be adequate. If you want to get towards high fractions, there is discussion of this. At that point, you need to have seasonal storage. Between these two different regions, having storage that would last for days up to week would have a clear benefit as well. This is the focus.

I should mention we published an article on this in January, if you want to learn about this in detail, you can check out the article.

One key point as you think about long-duration storage technology is the economics have to be fundamentally different than with lithium-ion. This is system lifetime cost over 20 year period versus the duration at rated power. The current commercial reality in terms of what's being installed is in the upper left-hand corner in gray. Last year it was over 90% of all storage products. If you look at the cost, it is going towards longer durations, with future cost reductions, there is some limit and how low the cost can go on a power per kilowatt hour basis.

If you compare that to something like pump storage hydro, where the energy cost is lower, you can see a huge discrepancy in how these two technologies scale as you go to longer durations. If you want to get a long-duration technology [Indiscernible] economics, [Indiscernible] the marginal costs of additional energy. There is a gap of what lithium-ion is going to do and you may want for other kinds of technologies. What kind of technologies are possible? We are looking at duration at rate of power versus power output. There is a lot of work today with lithium-ion. The systems can be deployed in projects that can become very big. Another common technology class for long duration storage is in chemical storage, like hydrogen or ammonia. One challenge there is its low routes of efficiency. The question is are there technologies that have above 50% [Indiscernible] proficiency, which is needed to have [Indiscernible] economics, would it really fit well into intermediate duration? Some technologies to look at would be things like flow batteries, low-cost reactance, mechanical or thermal systems, and Cliff talked about that earlier.

My last slide is, I wanted to mention the differences and importance of thinking about how new technologies would scale upI

I will talk about electrochemical technology like [Indiscernible]  a zinc-based battery. If you think about what kinds of investments are needed, for $10 million, you can do a reasonable amount of material work and prototyping in a laboratory. If you want to make a demonstration unit, you will roughly need $10s of millions to have a company that can make a pilot line and a careful cost analysis. This is where a lot of electrochemical technologies are not making it, in this demonstration stage.

If you want to go into manufacturing, you need to make an investment that is big enough that the resulting economics and the product are compelling compared to other alternatives to the marketplace. You compare that to something like a turbine-based thermal technology like a high-temperature rock-based unit with a heat exchanger, there's a big difference. One is turbines perform best at large scale.

Economically, in terms of their efficiencies and other attributes, really hundreds of megawatts. While you can still work in $10s of millions for material at the prototype level, demonstrations can become more expensive. Especially if you move away from sub-scale and move toward full-scale, first-of-its-kind demonstration projects. And carbon capture and [Indiscernible] filtration products are [Indiscernible] there. And, if you get a larger scale, those are also big projects.

There's been a lot of experience within DOE on concentrating solar power. As the DOE makes investments, it’s important to think carefully about the level of investments needed and the kind of technology structure as these things move from early-stage research into commercial performance. Thank you.

Thank you very much. I think that takes us to Frank Jacob from Black & Veatch. He will take all of this and translate that into what can be done commercially. Thank you, Frank.

Thank you for that simple assignment, Deepak.

Good morning, good afternoon from Kansas City, Missouri, home of the hopefully, long-duration Super Bowl champions. On Deepak’s panel of Technology Pathways, I'm talking about the downstream, commercial opportunities for long-duration storage.

They are on the left and side of your screen.

I just moved it for you.

Thank you.

I'm here representing the EPC community. The engineering, procurement and construction industry. All of the DOE-enabled technology developments will be hanging to EPCs to build for utilities, developers, owners, operators, generators, transmission operators, we will build for the grid. On the slide, for long-duration storage, are the gaps on the right that EPCs expect to be filled as your work proceeds from its concept to commercialization, that the technologies be bankable, that the authorities having jurisdiction are aligned with the permitting processes. That equipment warranties are reliable, that performance guarantees can be held, that risks are mitigated.

There is a lot of development to go on throughout those DOE pathways. These are not the things an EPC will do. This is what EPCs will expect you to have done to get to your commercialization end point. After all the concept-to-commercialization work is done through those really well-detailed DOE pathways, I show on this slide, deployment gaps on the right side that are often stumbling blocks to success.

Let's begin our journey, today, with that end in mind. First-of-a-kind technology (FoAK)—any EPC worth its balance sheet will be cautious about newly commercialized technology. A few decades ago, combined cycle, natural gas power plants were the new things. They were approached with deliberate caution, innovative engineering, and those then new combined cycle plants have become the workhorse of the power industry today. Efficient, reliable, fully wrap-able. So, the steps are to walk and jog before running.

You'll see in the FOA, a requirement to engage with an EPC firm in order to enter into your phase 2 development. Engage early, engage with the end in mind. Then, with that experience under our belts, there will be a first operator, then many operators of the successful technologies. This is the recipe for long-term success and the long-duration energy storage. Mind the gaps, fill the gaps.

This slide lists the big plans already announced for really big energy storage. Big in power, big in energy, big in duration. On the left side you will see in 2018, in California, Los Angeles and Department of Water and Power, announced adding pumped Hydro to the existing Hoover dam. What a project. A gap on the bottom is the uncertainty of energy prices. This is a 50, 75 or 100-year life project. How do make a project bankable? How do you get it built? In the middle, 2019, in Utah, Intermountain Powerplant, they announced the complete conversion of the coal-powered powerplant to hydrogen, with hydrogen being stored for seasonal energy use. This is done in underground salt domes below the facility.

What is the certainty around that technology? Let's get that worked out. Just a few weeks ago in Minnesota, the Great River Energy announced a new electrochemical technology with 150 hours of storage. Do you know how long 150 hours is? Just about six days. Six days of energy storage.

Keep in mind the traditionally long development times. Dr. Goodenough was mentioned today inventing lithium-ion in 1970, it was not commercialized until 1990. Mobile devices, it got on the grid in 2010 and it is here today and becoming bigger and bigger each year. How will be compress that development timeline for all these new electrical chemical technologies? The dream, our dream for long-duration storage is not a hallucination, it is a Grand Challenge. So, bidders, start your engines. Deepak?

Thank you. This has been a great set of discussions. What I would like to do before we move to the questions from the audience, maybe take a couple of minutes and have the panelists, including myself, talk about what they would like the audience to take away as a key challenge — one that is most significant in their minds. [Indiscernible] limit the achievement of scale and they have unintended consequence they would like to talk about and would be interested in hearing about that.

I want to take this chance to make a bridge between the previous panel that talked a lot about how storage would fit on the grid and the technologies we talked about here. A lot of the participants of the previous panel talked about this whole issue of inertia and frequency and dynamic response and the Duck Curve. Clearly that is an issue, but coming from the power electronics side, and Alex [Indiscernible] talk about [Indiscernible]. I'm not 100% sure we actually control [Indiscernible]. There is a better way to control it and a fundamental reevaluation of what types and what it looks like.

Sometimes, as Tom Overbye mentioned, it is going to run on a system when you have very light [Indiscernible] of machines [Indiscernible] and the system left to figure out how to do it [Indiscernible].

There are fundamental things here that need to be done. It certainly seems doable. When we go into new universe, let's not assume that the new universe looks exactly like the old one, the foundations may be there. That is one of the things I'm worried about that we’re not approaching properly, power electronics and power [Indiscernible] need to talk more together than we are doing right now.

With this question in mind, what is the fundamental key challenge and what are risks in terms of achieving scale? Why don't we open it to the panel and start with Cliff.

Was at directed to me?

It was directed at the whole panel. If you want to take command it … What do you think is a major challenge to overcome to reach scale, and is there an consequence we need to worry about?

I take that.

Go ahead.

I think the main challenge we face is to drive the costs of storage down significantly so that storage can become competitive with natural gas. This means getting the storage costs down by maybe a factor of two or three. In order to be able to be competitive. That is a real challenge because of the materials involved.

So, there has to be some fundamental advances at the materials level, using materials for which we have already got a significant supply chain. We will not develop a huge supply change in the future. And, being able to get the cost down. You have to get it down to the range of $40 or $50 per kilowatt hour or even less. That's a huge challenge and will require to move probably from intercalation chemistries as a fundamental to conversion chemistries, when you look at it from a very fundamental electrochemistry perspective. That is the barrier.

Thank you. Anybody else?

Can I comment? This is Paul. One challenge for developing new storage technologies for the grid in particular is the relative lack of high-value, first markets. And, if you look at, you basically have three rechargeable batteries that have ever really achieved significant scale, lead acid, nickel metal hydride, nickel cadmium, and lithium-ion—all those are really developed for portable applications, cars or phones or things like that, there's high-value and significant high-value markets for a long period of time.

I think lithium-ion at a few tens of billions of high-value market development before it had vehicles, as Frank mentioned, only after that, it made it to the grid. How do you get a new storage technology directly to the grid where everyone wants to have low cost without going through where the first few tens of billions of dollars to develop industry and help out with good margins. To the point about using the existing supply chain as much as possible is a key idea but it is a challenge. It is one thing everyone that develops new storage technology does face.

Thank you. Does anyone want to add something to it or we could go to questions. Similar, right. Meredith? I will transition it to you.

Very good. Please continue to send your questions to the chat box and reference a speaker or topic when you do. We will throw this to the panelists. It seems we have a lot of energy storage types of different characteristics. What technology has the potential to meet 80% of them? Cliff? 

I can address that. I'm not sure what they mean by the different needs, one way to distinguish this in terms of time scale, for shorter duration, say 4-6 hours, it does appear that lithium-ion or other battery types are well-positioned to address that. A gap is in larger duration storage. Looking at pumped hydro or the thermal energy storage technologies I discussed earlier could address, perhaps, the longer duration, were talking days, people mentioned the need for seasonal. That is one way to split up meeting those temporal needs.

Okay. Very good. Alex, this next question is for you. To what extent are end-of-life concerns captured in balance of system costs for batteries?

Thank you. My understanding is the balance system costs I presented were from cost to implement storage systems [Indiscernible]. It is not captured in that cost calculation but I think it should be. Particularly, there is concern, environmental issues about disposal of batteries, various different kinds of batteries. My view is we should include environmental impact regarding the disposal of battery technology. And we [Indiscernible] also a more sustainable and include that in the cost calculation. There is another cost to calculate the actions, there are several pathways to compute the cost of energy to predict the life of energy utilization technology. We need to include a penalty in the end of life, disposal of the technology. I think that is a gap in the current discussion that we need to include that.

Okay, thank you. Cliff, the?, What is the typical roundtrip efficiencies of those three thermal storage technologies?

Thank you. I don't know if you go to slide 71?

The three technologies were sensible, latent and thermal chemical. For sensible, just storing energy as a temperature difference in a large, insulated vessel can be very, very high round-trip efficiencies. It has been measured to 99% if you have a well-insulated device. That is taking the efficiency, taking the thermal energy out divided by the thermal energy. Converting that to electricity requires a heat engine or some sort of power cycle which is where you have your most losses. The typical [Indiscernible] ranking cycles around 40% thermal to electrical efficient. DOE is working on other cycles such as the super critical carbon dioxide. This can be up to 50% efficient.

With regards to the other ones, the latent in the thermal chemical, similar basically as long as you don't use heat, you can have a high round-trip efficiency, in terms of the thermal energy storage. Getting it into electrical form, it requires, for example a fuel cell, hydrogen, I think the efficiency of that might be, not sure exactly what that is, something above maybe a difficult turbine. The high round-trip efficiencies in the storage, the biggest hit is converting it from thermal to electric which can be 40-60%.

Okay. Thank you. Paul, a question for you. How can we think about monetizing long-duration storage?

That's a good question. The first answer for that is, in similar ways, as we think about monetizing 8-hour or 10-hour systems today, there is a variety of possibilities, certain customers value your back up power. There is a clear monetary stream there. If you can replace diesel and gen sets, things like that, that is something on the order $500 per kilowatt per year is how they are typically valued. Something on that order. That is one value stream. Hospitals might have a 72-hour back-up requirement. If you want to play in that market, you may need to have that kind of duration.

There are other things, for example, capacity payment, I'm not up to date with the latest, there is a variety of rules that are being worked on and what duration your energy storage needs to have in order to receive a capacity payment. A longer storage duration, if you have tens of hours, it might be well beyond what is required. You could have a clear [Indiscernible] to receive a capacity payment. Similar for T&D deferral, having a 2-hour storage system would provide some ability to do transmission and distribution deferral, but having something the lasted a few tens of hours will put you into a different category in terms of having very firm T&D deferral. Those are some specific examples.

Great, thank you. Cliff, the next question is for you. Is there any threshold regarding the [Indiscernible] in terms of storage capacity below which thermal chemical energy storage may not be techno-economically viable?

Thanks. Right now, thermal chemical storage is a challenge, in general, economically. One of the challenges I mentioned before is the potentially high cost of materials. I think a lot of the research is trying to get the thermal chemical storage technology to a point that can be competitive with other methods and then taking it to the next level. The question is at what scale can that be done? That depends on the process.

Besides the reactor, there might be economies of scale to go bigger, but you could be limited in terms of process and capability which could drive you to smaller reaction chambers. It is a good question. But, right now, I think techno-economically, researchers are trying to address that in general.

Thank you. Frank, this next one is for you. You identified performance guarantees and warranties as requirements for new tech before any [Indiscernible] get involved. How can the Department of Energy support new [Indiscernible] tech to offer both guarantees and warranties?

That's an excellent question. Not to say before we would get involved, but before we would commit to building a 20-year life facility. Understanding the equipment, the warranties, look at today's situation. A lithium-ion battery system, 50 MW, 200 hours, commissioned today will have a 20-year life for more. Well, there has been lithium-ion on the grid for more than 10 years yet and the cells are using today were only manufactured for the first time last year.

This understanding of how technology involves and how to build into that balance a system EPC cost that was talked about so we don't make the technologies unviable from an economic standpoint. So, accelerated testing, understanding the mechanisms, modeling and simulation as well as even some guarantees.

Very good. Cliff, this question is for you. For thermal energy storage, what is the potential for pre-cooling homes and business facilities?

That's a good question. A lot of the things I talked about work geared towards electricity production but certainly, using thermal storage or even cold storage for pre-cooling or even heating homes is a possibility. That's one of the advantages of thermal storage. Depending on the temperature range, you can use that energy for other things such as higher temperature applications, electricity production to lower temperature applications of cooling or heating homes or space heating. So, it is definitely doable, there could be multiuse applications with thermal storage.

So, Paul, how can we monetize long-duration storage?

I think we had that one already actually. Oh, sorry about that. We did.

Cliff? What are the safety challenges each of the [Indiscernible] technologies you identified?

That's a good question. I think safety is an important issue that has to be recognized when dealing with large-scale storage with batteries, with lithium-ion, we’re aware of the safety challenges there. With thermal storage, anytime you are dealing with elevated temperatures, we have to be careful. Oftentimes with these large, building-sized tanks, if you are dealing with molten salt, are isolated in regions that are not heavily populated. The molten salts can react and produce gases. There've been incidents reported, although not toxic. They had mitigation measures and safety plans in place to deal with accidental releases or leaks.

With regard to the latent heat, talking about liquid air, or the molten silicon, anytime you're dealing with extreme temperatures, whether it is extreme hot or extreme cold, there has to be safety precautions put into place. All of these companies that are dealing with this have to have safety procedures in place.

Paul, a question for you. Can geothermal generation be considered a long-duration storage technology?

That's a good question. In the context of this program, we focused on electricity in and electricity out systems. As Cliff mentioned, there are ways of doing thermal in and electricity out. As far as I know, there's not much injection of heat underground and returned back to electricity again. Obviously in some sense, any generator is providing power to the grid and contributing to overall power production. I think you wouldn't consider geothermal generation as being a storage technology or long-duration storage technology.

Great. Alex, a question for you. What are the theoretically achievable lifetimes for modern, bidirectional, inverters for batteries—10, 20, 30 years or more?

 I [Indiscernible] the theoretical lifetime. You can always design this according to [Indiscernible] costs, so that's a short answer. Another way to look at the lifetime is we need to, usually, consider the designs by being more modular, that way, you can extend the system lifetimes without each individual component lasting a certain amount of time.

Okay. Great. Sanjoy, this question is for you. It appears that lithium-ion batteries with lower cost and modularity have a leg up over other technologies? What conditions and scenarios might change that?

Well, lithium-ion has a particular application where the lightness of the batteries health, which is EV. But in certain other stationary applications currently, lead acid is widely used as well. So, I think the developments in lithium-ion will drive towards more solid-state electrolytes which would improve safety, which is one of the considerations in deploying them widely in buildings, things like that, particularly in places like New York. here is also the move towards trying to improve energy density using silicon anodes, and third, trying to reduce the cobalt, this is a bit of a supply-chain issue in the cathodes.

The developments are always moving in lithium-ion, trying to secure the supply chain. One of the issues that face lithium-ion today, particularly in the U.S., is much of the manufacturing and the supply chain is an issue. Large manufacturers like Panasonic, LG Chem, perhaps BYD, [Indiscernible]. There are significant issues. Some issues are related to safety. Plus, the high cost of the materials [Indiscernible] took.

The cost, with regards to the materials will not be able to drive it down to the cost of really large-scale, low-cost storage. Alternatives would have to be found which use lower-cost materials. Currently, there are alternatives, I think advanced lead acid is being looked at. Sodium ion batteries are being looked at. I think manganese batteries are being looked at. And, these are all part of DOE’s Office of Electricity program currently.

Thank you. Paul, a question for you. Can geo-thermal generation be considered as a long-duration storage technology?

I think we have that one too.

Sorry about that.

Cliff, the electricity-to-electricity cycle efficiency of the fuel-based systems at 50% or less are fairly low. Are there R&D prospects for improvement or [Indiscernible] range?

That's a good question. I think the question was is the thermal [Indiscernible] less than 50%?  That's correct. The typical steam ranking cycle, is typically up to maybe about 40-42% thermal-to-electric efficient. DOE is hard at work looking at alternative cycles. One in particular that has been studied in recent years is the supercritical carbon dioxide [Indiscernible] cycle. They're hoping to get a single cycle efficiency of 50%, thermal to electric, which requires higher temperature inputs.

To get there drives the need for different materials, different heat transfer media and concentrating solar power. Typically, it was the molten nitrate salts, which can only go up to 600 degrees C. They have a large, next-generation program looking at different materials to get to higher temperatures to enable those higher thermal to electric power cycle efficiencies.

Okay. Just another one, we have a few more minutes for a couple more questions.

Please, put those into the chat and let us know which speaker and topic you would like us to address. Let's see here. We have a bunch coming in all of a sudden here. Let's see.

I'd like to go back to some of our question one panelist. We had a few we are not able to get to. So, Mark? A question for, let's see. Bob or Tom, would energy storage that offers authentic inertia be preferable than synthetic inertia?

Are these all for me I guess? Could you repeat that again?

Yeah, absolutely. Would energy storage that offers authentic inertia be preferable to synthetic inertia?

I don't know. The advantage of actual inertia is it is there and it is actual and you don't have to use a control system to synthesize it. The advantage of synthetic inertia, you don't have to synthesize what comes out of an actual machine. You have more flexibility but you have to add a control system to deal with it. You have to get into the questions of saying what signal are you sensing? And would probably be multiple frequencies. It would not necessarily have to be multiple frequencies.

This is Bob. In my opinion, natural inertia in rotating machines has one advantage in that it provides synchronizing torque. The effect on [Indiscernible] a change of frequency for a frequency event that is afforded by inertial response is nice but we can do better. We can do it faster with storage or any inverter-based resource that can move faster than three and a half seconds. There is a trade-off here. You lose the synchronizing torque but you gain in the responsiveness of the system by using the control system.

Okay. Sanjoy, this question is for you. Many new battery technologies are turning out to be improved or innovative forms of long-known battery technologies. How important is it to come up with new technologies versus re-examining the older chemistries?

That is a really great question actually. Whoever asked that question is absolutely right. Most of the technologies that we are pursuing today have been around for 30 years, for example, lithium-ion, that somebody pointed out was invented in the 70s and commercialized in the 90s and then eventually it entered the grid around 2010 and so on. These have been around for a long time, like lead acid, zinc manganese and so on. What is, sort of new, are flow batteries to some extent. They are at an early stage though. They also have been around for a while. I remember seeing a swimming pool at a utility which is going to be used at some point for a flow battery and it was never used.

So, really new ideas have not come forward very much. So, how electrochemical energy storage would benefit, I think, is not clear but it could possibly take 20-30 years to get a really new idea off the ground and into the market. That is one of the problems. And as was pointed out earlier, the early market opportunities needed to get some new technology at a viable state. It is really very difficult. I can't think of anything that is radically new right now that is on the horizon. Which has been thought of in one form or the other, or some form of, let's say, innovation on an existing chemistry ad technology. I think that is the best I can do.

Thank you. This next question is for Alex and Deepak. It is about power-to-grid application of electrical power. Is there any host that is currently engaged in this kind of research? How can we better guarantee the stability of electric transportation without disturbing network frequency?

Alex?

I can give a quick response. If I understood correctly, the question may be about [Indiscernible] grid application, charging the vehicle or the energy? Or the vehicle going back to the grade or the relationship to the stability? I think of this dealing with how the control layer of any system. You mentioned [Indiscernible] the discussion about synthetic inertia. The way to this application, it could be designed with a single chemical electrode to enhance the grid frequency. From an [Indiscernible] large part demand to charge the vehicle, one solution is storage technology in combination with the charger so the localized storage can provide the peak power needed to charge the vehicle quickly. This is some of the control solution. You can solve the issue [Indiscernible] at a large vehicle charging station.

Let me add a little bit. I think you address the [Indiscernible] grid issue. We did talk about the transportation of electricity. I do know if that meant being able to direct energy on the network from point A to point B. There are technologies available for that and I think it links back to control of the inverters. Maybe [Indiscernible], on the previous question from synthetic versus real inertia. I thing we have not been controlling the inverters very well.  

It is time to take a fundamental look at what the inverter needs to support the grid optimally. That is a fundamental question that DOE needs to be addressing. So I think that is [Indiscernible] transporting energy. {lots of missing copy here}

And our last question is for Eric. When will the roadmap be released for comment?

We are in the last stages of formatting, or finalizing the storage challenges. We hope to release it within the next few weeks.

 Very good. Thank you. We are coming to the end of today's workshop. We would like to take the opportunity to ask you all, our audience, some questions and get feedback.

In our chat box, we will post a link to the feedback form. Your comments are important to RTIC community. As we move forward with an energy storage challenge survey. This survey will remain open until May 29. Follow the link in the chat. We'll put a link in the email you received after the workshop today. We really want to thank everyone for being here today. All of our keynote speakers. All of our panelists for your time and energy.

We have one last speaker for you today. Bryce, I want to make sure that we have Andy now?

Can you hear me?

I can. I can. I'm happy to introduce Andy McIlroy. He is Associate Laboratories Director at Sandia National Laboratories. In his role, he provides leadership and management direction for Sandia's California laboratory for the [Indiscernible] center which includes staff in New Mexico, Texas and Alaska. In addition, he has primary responsibility for Sandia [Indiscernible] Energy and Homeland Security mission portfolio as well as California [Indiscernible].

Andy, I will turn it over to you for closing remark.

Thank you, I will try to be brief since I'm sure we're suffering from a bit of video conference-teleconference fatigue over the last couple of months.

This is been an exciting workshop. I've had a chance to listen in for most of it. I'm really delighted that DOE has identified interface storage as a potential topic for the Grand Challenge. It is certainly worthy of that. From Sandia, I tend to start off thinking about things from a national security context. I think, it is painfully all but obvious to all of us right now, there are ways our lives are under an increasing number of threats and these threats are evolving. The pandemic is probably the most obvious one because it is so in front of us right now.

One of the interesting things is a multifaceted nature of that threat. It is not just a health threat but it is also threatening our economy and has a huge impact to the energy sector [Indiscernible]. The way it has change the demand for electricity and the price of oil. Our electric system faces a wide range of threats and has quite a range of vulnerabilities that we have to think about these days.

These vulnerabilities range from aging infrastructure to cyber and physical attacks to severe weather events that we are increasingly facing. Just notice the headlines today, there is a huge cyclone that is about to hit India, and we are facing these more often in the U.S. as well, these huge hurricanes and other sorts of severe weather events. We need additional resources and tools for electrical infrastructure to be secure and resilience against these events.

Energy storage is really a key component to this resilient energy future. It will help us be resilient for industrial and residential needs as well as our national defense needs. And, as we have heard about today, energy storage has advanced a lot in recent years and lithium-ion batteries are prime example of that. We are using them widely in mobile electronics on a routine basis and increasingly they are powering the electric vehicles. Sitting in California, I literally can't walk outside without seeing a Tesla someplace around. The impacts are getting to be much more common there. The electrification of transportation is just beginning and the impacts will be large on electric infrastructure but also on energy storage.

They are driving advances in energy storage to reduce range anxiety and increase the adoption of batteries into the transportation sector. This focus on energy storage for transportation is important. But, grid scale storage is different, it is complementary in some ways to the portable energy storage that a lot of the research has been focused on to date. We can use batteries in the grid, we need to consider other technologies as were discussed today.

Grid scale energy storage is becoming feasible and that large-scale deployment will be critical for us as we look at integrating renewables increasingly into the infrastructure. These renewables provide a lot of benefit, of course, both around resiliency and around addressing climate change issues. In order to bring those renewables on, we have to have reliable, large-scale grid energy storage. This is what we need to enable for clean and resilient future.

As we look at increasing the deployment of electrified vehicles, as we look at increasing the deployment of renewables, we have to figure out how to incorporate grid energy storage as a key and common component of the electrical grid. We need advances in the current technologies as we heard the last question as well as thinking about enabling advances that are being imagined.

They may be older technologies but one's we haven't fully embraced as grid energy options such as thermal storage technologies that Cliff was talking about earlier. We need to think about new control and integration strategies. How to get these technologies successfully integrated into the grid in a reliable and robust way. Just the storage alone won't do it.

That integration into the full system is a key part of thinking about the future of grid scale energy storage. As we look forward, leadership in energy storage, R&D, and manufacturing is important to keep the U.S. [Indiscernible] secure and globally competitive. This Grand Challenge initiative from DOE will help the U.S. maintain leadership in that key area.

I really applaud DOE leadership for thinking about this as a Grand Challenge initiative. It is worthy and would be a terrific investment for the nation. So, thank you all, you are providing terrific leadership in this area and we look forward to the advances that will occur over the next years in this area. Thank you.

Thank you so much, Andy. Ladies and gentlemen, if you have not done so and are still interested, please register for our final two regional webinars. The dates are on the screen and we will provide a link in our follow-up email. So, thank you so much for your participation and all of your questions today. We look forward to having you join us today and have a wonderful day.  [Event Concluded]