Fluence Energy, a subsidiary of Siemens, and Excelsior Energy Capital have agreed to install 2.2 gigawatt-hours (GWh) of battery energy storage systems (BESS) in the US from 2025.

Excelsior will deploy Fluence’s Gridstack Pro product line, which will use battery cells manufactured in Tennessee and modules produced in Utah, utilising the Inflation Reduction Act’s (IRA) domestic content bonus.

Gridstack Pro is one of the first BESS projects set to qualify as domestic content under the IRA.mJohn Zahurancik, president of Fluence’s Americas business, said: “We are excited to support Excelsior on the deployment of 2.2GWh of Gridstack Pro. This deal is a testament to the competitiveness of US-manufactured battery storage systems.

“Excelsior and other customers see US manufactured products as a valuable way to mitigate uncertainties in their projects while supporting American jobs and local economic activity.”

Due to the intermittent nature of output from renewable sources such as wind and solar, BESS is critical to aligning supply and demand. BESS stores excess energy for times when there may be a shortage.

According to GlobalData, Power Technology’s parent company, the technology will help to drive down prices, as energy storage reduces costs by storing electricity obtained at off-peak times when retail prices are lower. During hours of peak demand, when grid electricity costs are high, the cheaper stored electricity can be used.

BESS projects have recently been expanding in the US. According to Renewable Energy World, the latest quarterly revenues for Tesla’s energy storage arm were $3bn, almost twice the amount in the same period last year.

With the industry expanding, Fluence should not find it difficult to find a producer for its battery modules in Utah.

“This agreement with Fluence will reduce battery supply risks for our projects, enabling us to fully realise the potential of our BESS investments and support the energy needs of local communities,” said Chris Frantz, partner of Excelsior Energy Capital. “Together, we aim to leverage our combined expertise to drive sustainable growth and innovation in the energy sector.”