The largest grid operator in the USA, PJM Interconnection, has requested one of its contributing power generators, Talen Energy, to postpone the retirement of four fossil fuel-fired power generation units in the state of Maryland by three years to alleviate threats to grid reliability.

Three of the four units that are scheduled to be retired at the Herbert A. Wagner Generating Station are oil fired, while the other runs on natural gas; they total 844 MW in generating capacity. As Reuters reports, the request comes after increasing issues with reliability driven by the rise of solar and wind power within the grid – such reliability issues surface during peak periods or times of low wind and diminished light.

PJM is planning around US$5 billion worth of transmission upgrades for the grid up to 2028, which it anticipates will improve reliability issues, allowing the units at the H.A. Wagner plant to then close. Talen Energy must comply with the request until then.