In letters sent to leaders in Congress and the White House, energy storage executives called for renewed attention to incentives that were included in the stalled Build Back Better Act.

The proposed standalone investment tax credit for energy storage was seen as a potential game-changer for the industry. But, like the total $550 billion in clean energy incentives and investments in the bill, the energy storage ITC has an uncertain future.

 The executives wrote "to urge all negotiating parties" to continue work on, and pass, the landmark climate change and clean energy reconciliation bill.

"Certainty in the tax provisions allows our companies to continue to develop energy and climate solutions at scale and to build a diverse and reliable energy portfolio to support residential, commercial, and public sector entities," the executives wrote in the letters, which were dated February 16.

Executives from ESS, Form Energy, Q Cells USA, and Malta were among the 69 to sign onto the letters.

Since is was passed by Congress in 2006, the ITC for solar energy deployments has driven 10,000% growth in the solar industry, according to the Solar Energy Industries Association (SEIA). The law does not provide incentives for standalone energy storage.

The Build Back Better Act included a 10-year extension to the solar ITC, which was preparing to phase down from 26% in 2022 to 10% for commercial and 0% for residential systems by 2024. The proposal also included direct pay provisions in place of the current tax equity credit structure.

The energy storage executives called the incentives critical for developers and manufacturers to reach the necessary scale to reach U.S. climate goals.