US Installs a Record 4.7 GWh of Energy Storage Capacity in Q4 2021

The U.S. energy storage system (ESS) market registered a record growth in new system installations with 4,727 MWh in the fourth quarter (Q4) of 2021, according to global research and consultancy firm Wood Mackenzie.

The latest ‘U.S. Energy Storage Monitor Report’ released by Wood Mackenzie in collaboration with American Clean Power Association (ACP) noted that Q4 2021 witnessed more capacity installed than the first three quarters combined.

While the grid-scale storage struggled to meet the expectations, the residential and non-residential storage segments contributed to the overall growth in the year and the final quarter.

Grid-scale ESS


The grid-scale energy storage segment nearly tripled year-over-year (YoY) to 3 GW/9.2 GWh in 2021. The segment was held back due to supply chain challenges delaying over 2 GW of capacity into 2022 and 2023. According to Wood Mackenzie, the delays in supply chain and interconnection queue processing will persist through 2024.

Vice President for Energy Storage at American Clean Power, Jason Burwen, said, “2021 was yet another record for the U.S. energy storage market, with annual installations of multiple gigawatts for the first time. Despite supply tightness leading to some project delays, the grid-scale market is still on track for exponential growth.”

The report outlines that the system component price gains were affected due to price rise in raw materials and transportation.

Residential ESS

According to the report, Q4 2021 saw the residential ESS segment reaching a new record high with 123MW installed capacity, surpassing the previous high of 110 MW installed in Q1 2021. The increase in the solar-plus-storage sales in markets outside California resulted in taking the national annual to 436 MW, setting a new quarterly benchmark.

The report predicts that by 2026, annual ESS installations in the residential segment are likely to hit 2GW/ 5.4GWh — with frontrunners in California, Puerto Rico, Texas, and Florida leading the specific market segment.

Wood Mackenzie analyst Chloe Holden observed, “Puerto Rico’s position in the residential U.S. solar-plus-storage market comes as no surprise, and demonstrates how outages can drive battery adoption, with thousands of new residential installs emerging each quarter and competition increasing between local installers. Outages in Puerto Rico also drive customers to recognize the added value of resilience that solar-plus-storage systems offer, despite premium pricing and lack of incentive programs. This is also driving solar-plus-storage market growth in Florida, the Carolinas, and parts of the Midwest.”

The report also found that California storage markets remain resilient as the policy and market developments help the growing solar market.

The non-residential ESS segment delivered 131MWh in Q4 2021, resulting in 162MW/ 350MWh of total installations in the year. The demand was driven by increased storage attachment rates with the community solar markets of New York and Massachusetts.

The U.S. Department of Energy recently issued two notices of intent to invest $2.91 billion to enhance the production of advanced batteries to boost the growing electric vehicle and energy storage segment.

According to Wood Mackenzie’s recent analysis, the cumulative lithium-ion battery capacity will likely rise over five-fold to 5,500 GWh between 2021 and 2030.

Wood Mackenzie had previously reported that the U.S. installed 3.51 GWh of new energy storage in Q3 of 2021.