US Patent 12123347 Pumped heat energy storage system with load following

A method including: operating a pumped-heat energy storage (“PHES”) system in a generation mode to generate electricity; and responsive, at least in part, to a determination that a power generation plant will reduce supply of electricity to an electrical grid by a reduction amount of electricity, changing modes of the PHES system from the generation mode to operate in a charge mode. Operating in the charge mode can include receiving a charge amount of electricity, at least equal to the reduction amount of electricity, into the PHES system from the power generation plant and converting at least a portion of the charge amount of electricity to stored thermal energy.