As extreme heat events become more frequent and prolonged, grid operators are discovering that current battery energy storage systems (BESS) may not be equipped to handle the strain.
“We’re trying to optimise the grid versus build for that quarter of a percent of the year”—referring to extreme peak demand days. “We’re trying to come closer to that max line, and so it’s less pointy and more rounded. That requires longer duration storage. It just does,” Sisto says.
Most deployed grid batteries today offer 1-hour to 4-hour duration, which is enough to shave peak demand, but insufficient for multi-day heatwaves.
“As we start to get into more generation constraint, that obviously needs to stretch longer,” Sisto notes.
Sisto cites a figure from a recent Bloomberg conference, stating that approximately 70% of US power generation is approaching retirement age between now and 2035. Gas plants and fossil fuel infrastructure will either need to be fully replaced, or there will need to be a transition to renewables backed by long-duration energy storage (LDES).
