Counter-rotating reversing energy storage turbo machine

An apparatus for transferring energy in an energy storage system, comprising:

• a cold turbo machine having a plurality of blade rows, wherein a blade of at least one blade row of the plurality of blade rows of the cold turbo machine has a leading edge geometry that is substantially the same as a trailing edge geometry;
• a hot turbo machine having a plurality of blade rows, wherein a blade of at least one blade row of the plurality of blade rows of the hot turbo machine has a leading edge geometry that is substantially the same as a trailing edge geometry, and wherein a common shaft operably joins the plurality of blade rows of the cold turbo machine and the plurality of blade rows of the hot turbo machine;
• and
• a motor/generator operably engaged to the common shaft, wherein, in a first mode, electricity is supplied to the motor/generator which drives the common shaft such that the cold turbo machine operates as a turbine and the hot turbo machine operates as a compressor, and wherein, in a second mode, the cold turbo machine operates as a compressor and the hot turbo machine operates as a turbine to rotate the common shaft such that the motor/generator produces electricity.

An energy transfer system, comprising:

• a turbine and a compressor arranged on a common shaft, wherein a motor/generator is operably connected to the common shaft;
• a hot reservoir having a higher temperature than a cold reservoir;
• wherein, in a first mode of operation, a working fluid flows from the cold reservoir to an inlet of the compressor where the working fluid is compressed and exits through an outlet of the compressor at a higher temperature;
• wherein the working fluid flows from the compressor to the hot reservoir where the working fluid further increases in temperature;
• wherein the working fluid flows from the hot reservoir to an inlet of the turbine where the working fluid causes the turbine to rotate the common shaft, which causes the motor/generator to produce electricity;
• wherein the working fluid exits through an outlet of the turbine at a lower temperature and returns to the cold reservoir;
• and
• wherein, in a second mode of operation, electricity is supplied to the motor/generator to rotate the common shaft, the working fluid flows in the opposite direction, the turbine functions as a second compressor, and the compressor functions as a second turbine to transfer heat energy from the cold reservoir to the hot reservoir.