U.S Department of Energy Secretary Ernest Moniz on Dec. 12 released the agency’s Grid Energy Storage report to the members of the Senate Energy and Natural Resources Committee.
The report was commissioned at the request of Sen. Ron Wyden, D-Ore., the Committee Chairman. It identifies the benefits of grid energy storage, the challenges that must be addressed to enable broader use, and the efforts of DOE, in conjunction with industry and other government organizations, to meet those challenges.
“Energy storage is a vital component of a more resilient, reliable and efficient electric grid,” said Moniz. “We must continue developing innovative energy storage technologies and finding new ways to ensure wider adoption to help move the nation closer to the grid of the future.”
The report identifies four challenges that must be addressed to enable energy storage: the development of cost-effective energy storage technologies, validated reliability and safety, an equitable regulatory environment, and industry acceptance.
The need for energy storage in the electric grid is increasing as a result of the growing use of renewable power generation, which varies with wind and solar conditions, and increasing frequency of severe weather caused by climate change. The grid’s evolution toward more distributed energy systems and the incorporation of electric vehicles and plug-in hybrids also contributes to the growing interest in grid storage, DOE noted.
“Developing and deploying energy storage opens the door to adding more renewable power to the grid, which is essential to the fight against climate change,” Wyden said. “Energy storage will also help lower consumer costs by saving low-cost power for peak times and making renewable energy available when it’s needed the most, not just when the wind is blowing or the sun is shining. I’m looking forward to working with Secretary Moniz to find ways to implement the DOE’s recommendations to make energy storage an integral part of our country’s electricity grid.”
The storage report, developed with input from industry, academia, and government stakeholders, identifies efforts to address each of the four key challenges. Some of the key strategic actions are:
- Cost-competitive energy storage technology can be achieved through research, resolving economic and performance barriers, and creating analytical tools for design, manufacturing, innovation and deployment.
- The reliability and safety of energy storage technologies can be validated through research and development, creation of standard testing protocols, independent testing against utility requirements, and documenting the performance of installed systems.
- Establishing an equitable regulatory environment is possible by conducting public-private evaluations of grid benefits, exploring technology-neutral mechanisms for monetizing grid services, and developing industry and regulatory agency-accepted standards for siting, grid integration, procurement and performance evaluation.
- Industry acceptance can be achieved through field trials and demonstrations and use of industry-accepted planning and operational tools to incorporate storage onto the grid.
Almost all current U.S. energy storage is pumped hydro
Currently, the U.S. has about 24.6 GW (about 2.3% of total electric production capacity) of grid storage, 95% of which is pumped storage hydro. Europe and Japan have notably higher fractions of grid storage.
Energy storage technologies—such as pumped hydro, compressed air energy storage, various types of batteries, flywheels, electrochemical capacitors, etc. – provide for multiple applications, including energy management, backup power, load leveling, frequency regulation, voltage support, and grid stabilization. Importantly, not every type of storage is suitable for every type of application, motivating the need for a portfolio strategy for energy storage technology, the DOE report said.
The report noted that California, often an energy technology leader, enacted a law in October 2010 requiring the California Public Utilities Commission (CPUC) to establish appropriate 2015 and 2020 energy storage procurement targets for California load serving entities, if cost effective and commercially viable by October 2013. In February 2013, the CPUC determined that Southern California Edison must procure 50 MW of energy storage capacity by 2021 in the Los Angeles area. Additionally, in June 2013, the CPUC proposed storage procurement targets and mechanisms totaling 1,325 MW of storage.
Other states are looking to the example that California is setting, and Congress has introduced two bills that establish incentives for storage deployment, the report said.
Storage can “smooth” the delivery of power generated from wind and solar, in effect increasing the value of renewable power, the report said. Additionally, when energy storage is used with distributed generation, it can improve the reliability of those assets by providing power-conditioning value, and enables increased renewable penetration to help contribute to meeting state renewable portfolio standards.