Citing delays of large-scale energy storage projects and a slower-than-expected second half of the year for behind-the-meter batteries, Wood Mackenzie Power and Renewables slashed its forecast for U.S. storage deployments in 2019 to 478 MW, down from an estimate of 642 MW in March.
The tempered expectation would still equal 54% growth compared with the 311 MW the research firm cited for 2018, but highlights the challenges of forecasting the still-young storage market.
The downgrade, noted in a market report released Sept. 10, follows a series of reductions in Wood Mackenzie's forecast for 2018. The U.S. energy storage industry also notched solid double-digit growth last year, though the firm gradually reduced its outlooks over the course of 2018, pointing to tightness in equipment supplies as lithium-ion batteries were diverted to electric vehicles and a strongly incentivized market in South Korea.

The weakened forecast came as the industry deployed 75.9 MW in the second quarter, up 20% from a year ago, the report said, fueled largely by home battery demand met by residential solar specialist Sunrun Inc. and other companies. The 35 MW of residential storage added in the quarter was a record, according to the report.
"The nascent energy storage market in the U.S. continues to grow in fits and starts," Dan Finn-Foley, head of energy storage for Wood Mackenzie Power & Renewables, said in a news release. He pointed to a "massive" project pipeline, totaling more than 30,000 MW, that indicates an installation surge in the 2020s.
Although analysts reduced their forecast for 2019, they lifted their estimate for annual installations by 2024 to 4,834 MW, up more than 380 MW from their March forecast.
"The long-term growth trends of energy storage deployment nationwide are encouraging and consequential for stakeholders, and for all electricity users who want and deserve a more resilient, efficient, sustainable and affordable electricity grid," added Kelly Speakes-Backman, CEO of the Energy Storage Association.
Speakes-Backman encouraged U.S. lawmakers to accelerate energy storage additions with a federal investment tax credit for stand-alone projects. Currently, energy storage qualifies for federal investment tax incentives only when paired with solar power.
