The U.S. Department of Energy (DOE) Solar Energy Technologies Office Lab Call FY2022-24 funding program includes projects that are improving performance, reliability, and value of photovoltaic (PV) modules and balance-of-system components, as well as advancing characterization, monitoring, and data analysis for PV cells, modules, and systems.
Approach
PV projects are awarded in two topics, the first of which is PV Systems Improvement. Projects in this topic will conduct inverter reliability research, test other components like meters and mounting structures, develop quality assurance and best practices for PV installations, and test PV system performance and reliability under extreme weather conditions. The second topic is Advanced PV Characterization, Monitoring, and Data Analysis Methods. These projects will enhance the available capabilities at labs and help translate research results into real-world reductions in energy costs. In addition, this lab call funds core capability projects, which are comprised of enduring intellectual and physical assets that are designed to address long-term, difficult challenges associated with solar energy. These assets are not easily duplicated and have a unique, world-leading component.
Objectives
More than 20% of the hardware costs in a utility-scale PV system are spent on components other than modules and inverters. Durable, high-performing components will help PV deliver more energy, longer system life, improved system resilience, safety, and lower costs. Additionally, these lab projects support the development of advanced characterization, monitoring, and data analysis, including machine learning and artificial intelligence methods, for PV cells, modules, and systems that lead to lower manufacturing and operating costs, improved performance, enhanced predictability, and increased reliability. These projects will also create more pathways to disseminate PV research and ensure the industry and research community have the tools they need to further reduce costs.
Projects
Project Name: Advanced Diagnosis and Accelerated Testing of Balance of System Components for Utility-Scale PV Installations
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: David Miller
Project Summary: This project studies the durability of balance-of-system components, specifically wire harnesses (or cable jackets) and connectors within the power transmission chain. The research team will collect failed samples from utility PV installations to investigate the failure modes and the related enabling practices occurring in today’s PV systems. Samples will be studied using accelerated stress testing to aid understanding of the component durability relative to its application. Component- and material-focused failure analysis will be conducted to advise the PV industry. In-depth characterization will be applied selectively to field- and artificially aged-samples, to gain scientific understanding of the structural, chemical, electrical, mechanical, and thermal properties enabling degradation.Project Name: Connector Reliability Across the U.S. Solar Sector
Lab: Sandia National Laboratories
Location: Albuquerque, NM
Principal Investigator: Laurie Burnham
Project Summary: This project encompasses a multi-pronged investigation of PV connector health in the U.S. solar sector and an analysis of the implications of connector degradation and failure for short- and long-term performance, reliability, and levelized cost-of-energy (LCOE) calculations. The team will conduct a quantitative assessment of failure rates, root causes and mechanisms, involving in-situ diagnostics and data collection, lab-based forensics, as well as the economic costs and LCOE impacts of under-performing/failed connectors. The goal is to make the U.S. solar sector more robust, first by identifying and quantifying the risks to commercial- and utility-scale PV systems posed by poorly installed, mismatched and/or poorly designed and manufactured connectors; and second by conveying project data and findings to stakeholders, including standards bodies, manufacturers, Engineering, Procurement and Construction contractors (EPCs), investors, and underwriters, who have the tools and means to mitigate the risks.Project Name: Harnessing Sensor Data for Degradation Analytics and Operations and Maintenance Optimization in PV Systems: A Prognostic Approach
Lab: Argonne National Laboratory
Location: Lemont, IL
Principal Investigator: Feng Qiu
Project Summary: Operations and maintenance (O&M) effectiveness is a key enabler for enhancing PV competitiveness. Records from the wind, automotive, and manufacturing sectors demonstrate that real-time sensor data can provide significant opportunities for improving O&M. The PV industry, especially the inverters that remain the root cause for 43% of PV system failures, has not experienced a similar sensor-driven breakthrough in O&M. This project aims to develop a Prognostics-Driven O&M policy that models the behavior of asset degradation processes over time to determine the current state-of-health of the assets, forecast the trajectory of degradation to generate accurate predictions on the remaining life distribution, and optimize O&M decisions based on the sensor-driven prediction on asset remaining life. The proposed prognostics-based O&M will quantify the risk of every possible O&M schedule in the future and enable a proactive fleet-wide O&M scheduling plan.Project Name: Maturing Solar PV Racking and Module Mounting Critical Bolted Joint Technologies for Levelized Cost of Energy (LCOE) Reductions and Increased Reliability
Lab: Lawrence Berkeley National Laboratory
Location: Berkeley, CA
Principal Investigator: Gerald Robinson
Project Summary: This project lays the foundational steps needed to move toward highly robust bolted joints in PV module racking and mounting, a critical and often overlooked component of solar technologies. Bolted joints lack the technological maturity exhibited in comparable industries to deliver low-cost and highly reliable solutions that are critical for further advancement of the industry. By utilizing well-established methods and tools, this research effort will fill knowledge gaps through structured interviews of key stakeholders, modeling and lab testing of common bolted joints. The project will then develop a technical guidance document backed by empirical evidence targeting product engineers and standards committees.Project Name: Single-Axis Tracker Reliability and Performance Improvement
Lab: Sandia National Laboratories
Location: Albuquerque, NM
Principal Investigator: Daniel Riley
Project Summary: This project combines Sandia’s research strengths and long-standing experience in the PV industry to improve the reliability, performance, and market maturity of single axis tracker (SAT) systems. The research team will work with U.S.-based SAT manufacturers to improve the relevance of qualification standards to horizontal SATs, which are most prevalent and provide the lowest levelized cost of energy (LCOE) in the solar industry today. The team will also develop new performance data evaluation tools and sensor systems that aid system owners and operators in predicting and preventing failures of tracking systems. Additionally, the team will develop algorithms to optimize tracking of SAT systems to capture more energy in diffuse lighting and low sun angle conditions. New, publicly available performance models for optimized system design and performance validation will be made available to the public.Project Name: Snow: Increasing the Resilience of Photovoltaic Systems in Northern Latitudes
Lab: Sandia National Laboratories
Location: Albuquerque, NM
Principal Investigator: Laurie Burnham
Project Summary: The vulnerability of PV systems to extreme weather, including heavy seasonal snowstorms, has raised increasing concern among solar industry stakeholders, ranging from utilities dealing with generation losses to asset owners wanting predictable performance, to insurers and investors concerned about the performance risks of snow shading and the reliability risks of snow loading. This project aims to quantify snow losses across a range of technologies and system designs to increase the overall efficiency of PV systems installed at northern latitudes. The data generated will inform product development, improve installation designs and practices, and generate more accurate performance models, giving stakeholders greater confidence in levelized cost of energy (LCOE) calculations and the life expectancy of PV plants in northern regions of the United States.Project Name: Development and Application of Voltage Loss Analysis for Advanced Thin Film PV
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Darius Kuciauskas
Project Summary: Thin-film solar cell efficiency and reliability improvements require voltage-loss analysis to include band-tail effects, contact selectivity, and correlations between interface chemistry and electro-optical properties. This project is developing and validating experimental and computational characterization tools to be used in collaborative research with industry and academic labs to increase efficiency and reliability of thin film solar cells. The project will focus on understanding how device and material electro-optical properties derive from the chemical composition. Device models and modeling codes will integrate experimental data with semiconductor band structure, defect models, and solar cell optics.Project Name: PVInsight Phase 2
Lab: SLAC National Accelerator Laboratory
Location: Menlo Park, CA
Principal Investigator: Bennet Meyers
Project Summary: This project builds on the work and experience of the PVInsight project and addresses modern data challenges in the residential, commercial, and utility sectors of the PV solar industry. The research team aims to develop data science tools to enable cost-effective, fleet-scale operations and maintenance for all PV systems, including systems that have lower data quality, are not well modeled, and are lacking reliable environmental data. The team will utilize a signal-processing framework for analyzing PV performance signals, which enables the analysis of unlabeled time-series data.Project Name: Electrically Detected Magnetic Resonance for Identifying Defects in Wide Range PV Devices and Materials
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Paul Stradins
Project Summary: This project is developing and adapting a very sensitive magnetic resonance technique – Electrically Detected Magnetic Resonance (EDMR) – to identify atomic origins of performance- and reliability-limiting defects in PV cells and modules. This includes identification and mitigation of defects in the forefront silicon PV technologies, and defect identification in degraded modules. The project will also establish state-of-the-art EDMR capability at the lab. EDMR, with extreme sensitivity for identifying microscopic origins of performance and reliability-limiting defects, will advance new high-performance technologies in mainstream and emerging PV.Project Name: DOE PV Fleet Performance Data Initiative
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Chris Deline
Project Summary: This project leverages PV data to develop models and understanding of the field performance of existing and new technologies. The research team will report on field performance and degradation rates for high-efficiency silicon and more conventional technologies, develop automated analysis techniques to quantify system performance, refine the RdTools software toolkit to apply standard and validated analysis techniques to partner data, and inform data quality assurance by other software tools. Additionally, the team will collaborate with large-scale fleet owners to publish performance details for a major cross-section of deployed U.S. systems and disseminate findings and data. Improved analysis and reporting of PV field performance increases the certainty of owners and financers that systems will perform as expected.Project Name: DuraMAT 2
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Teresa Barnes
Project Summary: This project manages the Durable Module Materials (DuraMAT) Consortium, which brings together DOE national lab and university research capabilities with the PV and supply-chain industries to accelerate solar electricity generation through five core objectives: development of a central data resource for PV modules, multi-scale and multi-physics modeling, disruptive acceleration science, forensic tools for fielded modules, and materials solutions for more durable, reliable, and resilient modules. DuraMAT leverages the decades of experience, expertise, and world-class facilities at the national laboratories to create a “one-stop-shop” for timely solutions to critical barriers limiting module reliability and durability. DuraMat 2 will identify which materials and packaging designs will enable high energy yield modules with the potential for 50-year lifetimes and identify long-term degradation mechanisms and failures.Project Name: PV Reliability Core Capability: R&D to Ensure a Scientific Basis for Qualification Tests and Standards
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Ingrid Repins
Project Summary: This core capability project is performing research and development that leads to science-based tests and standards that can better ensure PV system reliability and quality. The team will design and perform accelerated stress tests on PV products and then correlate the results with successes and failures of PV products in the field. Testing will focus on the module package—including the glass and frame, interconnection devices, and solar cells—and the micro-characterization of both failed and healthy modules to help improve test accuracy and predictive ability. The new tests will help PV system owners better predict long-term safety and energy generation of different products while lowering the cost of PV electricity by extending the lifetime of PV modules.Project Name: PV Proving Grounds Core Capability
Lab: Sandia National Laboratories
Location: Albuquerque, NM
Principal Investigator: Bruce King
Project Summary: This core capability project conducts field research to better understand how PV systems function under real-world environmental operating conditions. Core field laboratories are located at the Photovoltaic Systems Research Laboratory at Sandia and the Outdoor Test Facility. These two sites maintain similar outdoor capabilities and are supported by complimentary indoor module characterization laboratories. The PV Proving Grounds leverages independently managed remote sites in Nevada, Florida, and Michigan to enable research in a variety of extreme climate zones within the United States. Collaborative field research in partnership with U.S. industry will validate new technologies and accelerate product development. Long-term observation of fielded PV systems, selected for novelty and technical diversity, will aid in assessing non-linear degradation, emerging failure modes and correlating observations with accelerated testing. The project will also carry out independent assessments of emerging PV technologies, including novel PV modules, monitoring systems, and balance of system components. The performance data from this project will be made available to the PV industry and U.S. companies will be able to directly interact with the national labs, giving them access to national experts and performance assessment tools.Project Name: Solar Radiation Research Lab
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Manajit Sengupta
Project Summary: The Solar Radiation Research Laboratory (SRRL) is a world-leading solar calibration and measurement facility and maintains the World Radiation Reference, which is essential for traceable and accurate measurements of solar radiation at all solar generation facilities. The Baseline Measurement System at SRRL provides a high-quality record of solar irradiance and surface meteorological conditions. SRRL capabilities are used to develop improved methods for the calibration of solar radiometers as well as new standards, models, and advanced instrumentation and methods for operating solar measurement stations. The SRRL datasets are also critical for validation of new models and datasets such as the National Solar Radiation Database. Research and development of solar radiation measurement systems and resource modeling techniques are essential for advancing the scientific basis for producing reliable resource data.Project Name: PV Performance Modeling Core Capability
Lab: Sandia National Laboratories
Location: Albuquerque, NM
Principal Investigator: Joshua Stein
Project Summary: This core capability project supports a variety of improvements to PV performance models, creation of an energy rating approach and datasets for the United States, development of a model validation framework, and support for the open-source modeling package, pvlib python. The project will also continue to support the PV Performance Modeling Collaborative and activity leadership in the International Energy Agency Photovoltaic Power Systems Programme Task 13 working group. The objective of this project is to increase the value of PV performance models by improving their functionality, demonstrating and quantifying their validity, and offering a wide range of stakeholder engagement opportunities.Project Name: Advanced Perovskite Cells and Modules
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Joseph Berry
Project Summary: This core PV capability project examines critical materials, integration, and device issues required to propel the development of halide perovskite solar cells (HPSC) technologies. This project will use a scientific approach to understand the roadblocks and risks associated with commercializing HPSC technologies, including any challenges to fully scalable manufacturing and long lifetime field operation. This project will focus on stability research to better understand mechanisms that cause degradation and failure in HSPC and develop device stability acceleration factors that can be applied across relevant halide perovskite materials for PV and associated device architectures. This work will be device-centric but have a materials-driven emphasis in order to overcome the efficiency, stability, and scalability challenges preventing HPSC from reaching $0.03 per kilowatt-hour by 2030.Project Name: Advanced Thin-Film PV Core Capability (Cadmium Telluride)
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Matthew Reese
Project Summary: Cadmium telluride (CdTe) is the current cost-leading PV technology, directly competing with silicon PV at scale, even when manufactured in the United States. The efficiency of CdTe doped with copper, however, remains lower than theoretically possible, and improvements need to be made in carrier concentration, minority carrier lifetime, and interface recombination. Using a new defect chemistry with group V doping instead of copper has been identified as a viable route for these improvements using single crystal systems. This project will implement this new defect chemistry in scalable, polycrystalline, thin-film CdTe devices with tasks focusing on improvements to the front interface, absorber, and rear interface.Project Name: Hands-On Photovoltaics Experience Core Capability
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Adele Tamboli
Project Summary: Hands-On PV Experience (HOPE) is a one-week summer school program held at the National Renewable Energy Laboratory (NREL) each year to train graduate student PV researchers in PV fundamentals, as well as specific cell technologies and techniques in measurement and characterization. The program brings in students from across the United States and their faculty advisors for an in-depth, intensive program that includes hands-on lab experiences in solar cell fabrication and testing. This program aims to train future PV researchers and increase collaboration among the students, faculty, and staff at NREL. To improve the program in FY2022-24, the team will use previously recorded content to streamline the workshop, increase outreach to groups that have not collaborated with the lab, and increase module- and systems-level content.Project Name: III-V PV Cell Core Capability
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Myles Steiner
Project Summary: This project focuses on reducing the costs of III-V photovoltaic modules for domestic energy production applications, through research into multijunction cell fabrication that incorporates substrate reuse. The project will investigate techniques to grow high-efficiency tandem solar cell structures on low-cost substrates by both metalorganic vapor-phase epitaxy (MOVPE) and hydride vapor phase epitaxy (HVPE) growth platforms. They will continue efforts to engage with industry stakeholders by collaborating, where possible, on other substrate removal technologies as well.Project Name: PV Cell and Module Performance Testing Core Capability
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Nikos Kopidakis
Project Summary: This core capability project maintains the National Renewable Energy Laboratory’s PV Cell and Module Performance Laboratory and provides access to PV performance measurements and best practices to U.S. universities, national laboratories, and the Solar Energy Technologies Office. Through its primary reference cell calibrations, this laboratory maintains the PV peak watt rating for the United States. This work assures that U.S. consumers, installers, and PV project developers can have confidence in the power ratings of the PV modules they purchase, enabling a more robust U.S. PV industry. This project also provides a world record of PV performance measurements, which is essential for tracking the progress of PV research and development.Project Name: Silicon PV Core Capability
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Paul Stradins
Project Summary: This project is developing silicon-based PV cell research and process engineering. The team will research concepts related to polycrystalline silicon/silicon dioxide passivated contacts, cell design and processing, and fundamental loss mechanisms in single crystalline wafers made by the Czochralski (Cz) process. The project aims to provide fundamental understanding and innovative solutions to the PV community in these areas to improve p-type passivated contacts, to explore lean processing of high-efficiency cells, and to help solve PV energy loss due to wafer lifetime degradation. This project also supports collaborative research efforts with academia and industry that advances the knowledge base of fundamental materials science, physics, and chemistry of silicon-based PV technologies.Project Name: Tandem Photovoltaic Devices
Lab: National Renewable Energy Laboratory
Location: Golden, CO
Principal Investigator: Emily Warren
Project Summary: Tandem or multijunction solar cells can convert sunlight to electricity with greater efficiency than single junction solar cells by splitting the solar spectrum across sub-cells with different bandgaps. Combining well-established photovoltaic technologies into a single tandem architecture holds promise for dramatically increasing total cell efficiency, but substantial development is needed to address the challenges of scaling hybrid tandems from “champion cells” to interconnected large modules. This project will fabricate tandem PV devices, focusing on a perovskite/silicon platform, assess performance and reliability, measure and model energy yield, and compare their performance and cost to industry-standard silicon PV. The objective is to demonstrate commercially relevant prototypes and understand their realistic costs, performance benefits, and trade-offs for different PV markets. Module-level concerns such as optical losses, stringing, bifaciality, and multi-cell interactions will be considered.