Energy storage installation with open charging circuit for storing seasonally occurring excess electrical energy

An energy storage installation for storing thermal energy, comprising:

• a charging circuit for a working gas, said charging circuit comprising a compressor, a heat accumulator and an expansion turbine, wherein the compressor and the expansion turbine are arranged on a common shaft, and wherein the compressor is connected at the outlet side to the inlet of the expansion turbine via a first line for the working gas, and the heat accumulator is incorporated into the first line, and the compressor is connected at the inlet side to a second line which is open to the atmosphere, and the expansion turbine is connected at the outlet side to a third line which is open to the atmosphere, such that a circuit is formed which is open to the ambient air, wherein the expansion turbine is connected via a fourth line for a hot gas to the heat accumulator, such that the working gas of the expansion turbine can be heated by heat from the heat accumulator, and
• a discharging circuit into which the heat accumulator and furthermore a steam turbine plant with a water-steam circuit are connected, wherein steam for expansion in the steam turbine plant can be generated by means of a heat exchanger.