Systems and methods are provided for generating electricity via a pumped thermal energy storage (“PTES”) system. A system may include a pump configured to circulate a working fluid within a fluid circuit, wherein the working fluid enters the pump at a first pressure and exits at a second pressure; a first heat exchanger; a second heat exchanger; a turbine positioned between the first heat exchanger and the second heat exchanger, configured to expand a first portion of the working fluid to the first pressure; a heat rejection heat exchanger configured to remove thermal energy from a second portion of the working fluid; a high temperature reservoir connected to the first heat exchanger; and a low temperature reservoir connected to the second heat exchanger.