How competitive is BESS for data centers, really?

A new industry report looks at how big battery systems (BESS) are being used to power data centers, the buildings that run cloud computing and AI. Companies like Google, Meta, Microsoft, Alibaba, and others are investing heavily in these battery installations alongside battery makers such as Fluence and Energy Vault.

The report, from Volta Foundation, finds batteries are winning the jobs that need speed and short bursts of power: shaving costs during expensive peak-demand hours and providing temporary "bridge" power while a data center waits to connect fully to the grid. Batteries are also holding their own in areas like handling brief power interruptions and fine-tuning power quality. But they're still losing out on jobs that need sustained power for long stretches — backup lasting more than four hours still goes to diesel generators, and continuous, round-the-clock power still mostly comes from gas turbines and fuel cells.

For homeowners, this is background on where the electric grid is headed rather than anything requiring action at home. Data centers are becoming a much larger source of electricity demand, and how that demand gets managed — whether through batteries, gas, or a mix — affects how strained and how priced the broader grid becomes. The report notes that regulators and grid operators still need to sort out clearer rules for how these large battery-backed facilities connect and interact with the grid, which could shape electricity costs and reliability more broadly in the years ahead.