Energy Storage

The document provides an overview of energy storage solutions, highlighting the transition from traditional pumped-storage hydropower to advanced battery technologies like lithium-ion. It details the technical trade-offs between different storage methods, the economic trends driving adoption, and the regulatory environment in the U.S. aimed at increasing grid flexibility and resilience.

• The International Energy Association (IEA) indicates that to limit global warming to below 2 degrees Celsius, global storage capacity must reach 266 GW by 2030, increasing from 176.5 GW in 2017. Bloomberg New Energy Finance projects the market will reach 942 GW by 2040, requiring $620 billion in investment.
• Pumped-storage hydropower (PSH) remains the dominant utility-scale storage method in the U.S., accounting for 95 percent of such storage. In 2015, the U.S. had 22 GW of PSH incorporated into the grid, and the technology grew by 2 GW over the preceding decade.
• Lithium-ion batteries dominate the global grid battery market with over 90 percent share due to high energy density and falling costs. Between 2010 and 2016, battery costs for electric vehicles fell by 73 percent, and prices for these systems are estimated to drop 8 percent annually through 2022.
• Large-scale battery storage in the U.S. is primarily managed by Independent System Operators (ISOs) and Regional Transmission Organizations (RTOs). As of the end of 2017, PJM had the highest capacity at 278 MW, followed by California’s ISO (CAISO) with 130 MW.
• Various storage technologies offer different performance profiles: Pumped hydro provides the highest max power rating (3,000 MW) and long lifetimes (30-60 years), while lithium-ion batteries offer higher efficiency (85-95%) and faster discharge times (1 min - 8h). Hydrogen fuel cells provide high energy density but remain expensive due to the need for platinum.
• Electric vehicles (EVs) can support the grid through vehicle-to-grid (V2G) technology or by repurposing retired batteries for stationary storage. In Elverlingsen, Germany, nearly 2,000 Mercedes Benz EV batteries were used to create a stationary battery with almost 9 MW of power.
• U.S. regulatory and funding efforts include FERC Order No. 841 (February 2018), which requires ISOs and RTOs to remove barriers to energy storage entry, and the ARPA-E DAYS program, which provided up to $30 million to develop storage capable of powering the grid for up to 100 hours.

APA

Zablocki, A. (2019). Energy Storage. Environmental and Energy Study Institute. https://www.eesi.org/papers/view/energy-storage-2019

Chicago

Zablocki, Alexandra. Energy Storage. Environmental and Energy Study Institute, 2019. https://www.eesi.org/papers/view/energy-storage-2019.

Wikipedia

{{cite report |last1=Zablocki |first1=Alexandra |title=Energy Storage |publisher=Environmental and Energy Study Institute |date=22 February 2019 |url=https://www.eesi.org/papers/view/energy-storage-2019 |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{zablocki2019energy, author = {Zablocki, Alexandra}, title = {{Energy Storage}}, institution = {Environmental and Energy Study Institute}, year = {2019}, month = feb, url = {https://www.eesi.org/papers/view/energy-storage-2019}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }