Nearly everyone recognizes that prudent development of domestic oil and natural gas resources will continue to be an important part of U.S. energy strategy for decades to come. How important depends a lot on conducting operations responsibly, ensuring communities are safe and the environment protected as the nation maximizes use of this vital domestic energy resource.
That’s where DOE’s ultra-deepwater (UDW) research program plays a significant role. Managed by FE’s Office of Oil and Natural Gas with the support of NETL, the UDW program’s mission is to work toward mitigating the risks and challenges associated with ultra-deepwater drilling and production operations. This includes deepening the collaboration and coordination already established with the Department of the Interior’s Bureau of Safety and Environmental Enforcement.
Only 30 years ago, “deepwater” oil and natural gas production referred to offshore wells in water depths of several hundred feet. Today’s deepwater operations are generally in the 1,000-to-5,000 foot range, and ultra-deepwater production can occur in water depths of between 5,000-to-10,000 feet or more.
Why are these resources important? Consider these facts:
- U.S. offshore oil and gas resources comprise 25 percent (about 4.6 billion barrels) of total proved crude oil reserves in the lower 48 states. Annually, they account for about 20 percent of total domestic crude production.
- They also make up nearly 6 percent (15 trillion cubic feet) of total U.S. natural gas proved reserves (263 trillion cubic feet) and provide about 10 percent of total annual dry gas production.
The Gulf of Mexico is one of the most important locations of U.S. offshore and deepwater resource production. This area produces 93 percent of all U.S. offshore oil and about 96 percent of offshore natural gas; DOI’s Bureau of Ocean Energy Management, Regulation and Enforcement estimates the Central Gulf alone holds more than 30 billion barrels of oil and nearly 134 trillion cubic feet of natural gas yet to be discovered.
Additionally, the Energy Information Administration (EIA) projects the deepwater contribution of domestic oil and natural gas supplies will continue to be significant in the years ahead, assuming ongoing technological solutions to improve production, increase safety and mitigate environmental impacts. By 2040, EIA forecasts crude oil production of 1.75 million barrels a day and 2.85 trillion cubic feet of natural gas from U.S. offshore resources in the lower 48 states.
Obviously, working in environments at UDW depths can pose special complex challenges not only to production, but also to worker safety and the environment, as the tragic Macondo/Deepwater Horizon incident of January 2011 emphasized.
As a result of Macondo, DOE UDW research shifted focus from maximizing value and increasing energy security to spill prevention, safety and environmental protection. This includes additional emphasis not only on improved understanding of systems risk, but also reducing risk through real-time data analysis and the development of advanced technologies.
NETL’s Ultra-Deepwater and Deepwater research is working to build the scientific understanding and assessment tools necessary to develop confidence in the safe and environmentally sustainable development of domestic oil and gas resources. Some examples of current projects within this portfolio include:
- Determining Physical and Chemical Behavior of Cement Barriers Used in Ultra-Deepwater Systems: NETL is researching the behavior of typical wellbore cements to better understand how cement formulations perform, with an emphasis on potential failure pathways and remediation technologies. Currently, there is no information on how foam cements, commonly used in extreme offshore settings, perform and persist under in situ conditions. NETL researchers initiated laboratory characterization studies of commonly used formulations of foam cements, obtained the first CT images of foamed cement systems, and developed a reliable methodology to analyze the microstructure of foamed cements under in situ conditions. Going forward, the team will use this methodology to determine stability of foamed cement systems at various “depths” in the subsurface.
- Quantifying Complex Fluid-Phase Properties Under High-Pressure/ High-Temperature (HPHT) Conditions: NETL is working to improve the accuracy of thermodynamic models under HPHT conditions, allowing for better characterization of reservoir fluids and the dynamics of these fluids during extraction. Improved models will decrease uncertainty associated with fluid quantity and flow at and near the borehole. Accurate understanding of the reservoir and associated well behavior is an important component of our ability to predict the behavior of wells. NETL researchers have expanded the density and viscosity databases for hydrocarbon compounds in HPHT conditions and integrated these results with existing data, resulting in a comprehensive database.
Additional information on these projects can be found here.
Working with its partners in industry and academia, NETL’s Strategic Center for Oil and Natural Gas and FE’s Oil and Gas Safety and Environmental Sustainability Research Division have collectively amassed wide ranging expertise in areas related to deepwater and UDW resource location, production, safety and environmental protection. While challenges associated with increasingly hard-to-locate-and-produce UDW resources will always be present to some degree, FE’s innovative research portfolio is making real progress toward ensuring this important domestic resource will fulfill its potential in a safe and sustainable way in the years ahead.