Clean energy storage & management solutions… based on Compressed air

Enairys’ Smart CAES concept

Most of applications require many types of energy (electrical, thermal, mechanical, etc.) simultaneously to meet their needs or achieve their goals.

Enairys has developed an innovative Compressed Air Energy Storage (CAES) concept where electricity is stored in by compressing ambient air into high pressure tank, while optimising the related thermal energies for local heating and cooling applications.

Enairys’ smart & efficient energy conversion unit includes innovative technologies that allow implementing smart synergies between electricity, compressed air, heat and cold, as illustrated beside.

This unique CAES concept allows improving the power supply quality, optimising the energy efficiency, reducing costs and minimizing environmental impacts.

Innovative CAES technology:

Enairys’ innovative CAES concept (so called HyPES: Hydro-Pneumatic Energy Storage) relies on natural physical principles, and smartly combines many patented technological innovations in the fields of power electronics and hydro-pneumatics to effectively perform the targeted energy synergies. The conceptual diagram below presents the main internal functional blocs of HyPES systems:

(1) Conversion & Management Unit

      (1.A)         Modular electrical power conditioning & management

      (1.B)         Electrical motor/generator

      (1.C)         Multistage near isothermal air compressor/expander

      (1.D)         Multistage heat exchanger

            (1.D1)            High pressure side air heat exchanger

            (1.D2)            High pressure side water heat exchanger

            (1.D3)            Low pressure side water heat exchanger

            (1.D4)            Low pressure side air heat exchanger

(2) Water tank

(3) Compressed air tank

Operating principle:

The operating principle of HyPES system is illustrated by the diagram below:
  • During the Charge or Storage mode (air compression), the electricity generated by electrical sources is appropriately conditioned and used to power the electrical machine operating in motor mode, which in turn drives the compressor/expander module in compressor mode. Ambient air is sucked in the unit (1) and efficiently compressed under near isothermal conditions thanks to continuous injection of cold water from tank (2), and then stored in the high-pressure tank (3).

    In the same time, cold can be imported from external cold sources (or thermal ballast) if available, through the integrated low-pressure heat exchangers, to precool the air and improve the compression efficiency or, low temperature heat (below 80°C depending on the ambient temperature) can be supplied to external heating applications (or thermal ballast) through the integrated high-pressure side heat exchangers.

  • During the Discharge mode (air expansion), compressed air from storage tank (3) is expanded in the compressor/expander module running in expander mode under near isothermal conditions thanks to continuous injection of water from tank (2). The resulting mechanical power is used to drive the electrical machine in generator mode. The generated electrical power is in turn conditioned to supply the loads or is fed into the grid.
    In the same time, heat can be imported, if available, from external heat sources (or thermal ballast) through the integrated high-pressure side heat exchangers in order to improve the expansion efficiency or, low temperature cold (down to -20°C depending on the ambient temperature) can be exported to external cooling applications through the integrated low-pressure side heat exchangers.

The originality and effectiveness of Enairys’ CAES solution rely on a smart combination of several cutting-edge patented technological innovations, mainly: