System and method for storing energy in form of compressed air in tubes integrated in a tank containing water and water vapour

1. A system for storing energy in compressed air, water and water vapor comprising:

at least one tube providing a storage volume for the compressed air, water and vapor water, the tube being confined in a sealed pressurized pressure-resistant thermally-insulated tank, means for storing and releasing heat in the compressed air stored in the storage volume and the sealed pressurized pressure-resistant thermally insulated tank includes compressed air, water and water vapor which during heat storage progressively vaporizes until a water-vapor medium in phase equilibrium occurs in the tank which depends on pressure and temperature in the tank.

2. A system as recited in claim 1 , wherein the at least one tube is metallic.

3. A system as recited in claim 1 , wherein the water and water vapor occupies at least part of an inner space of the tank.

4. A system as recited in claim 1 , wherein the at least one task includes connected straight tubes joined in bundles and arranged in parallel.

5. A system as recited in claim 1 , wherein the storage volume comprises a tube in a coil.

6. A system as recited in claim 1 , wherein the storage is disposed on either a ground surface or at least partially buried below the ground surface.

7. A system as recited in claim 1 , wherein at least one tube is substantially horizontal.

8. A system as recited in claim 1 , comprising a secondary heat exchanger for heating the means for storing and releasing heat.

9. A system as recited in claim 1 , comprising a heat source external to the tank for heating the means for heating and releasing.

10. A system as recited in claim 1 comprising a tertiary heat exchanges for heating the storage volume.

11. A system as recited in claim 1 , wherein the tank consists of a closed concrete shell having a thermal insulation coating.

12. A system as recited in claim 2 , wherein the water and water vapor occupies at least part of an inner space of the tank.

13. A system as recited in claim 2 , wherein the at least one tube includes connected straight tubes joined in bundles and arranged in parallel.

14. A system as recited in claim 3 , wherein the at least one tube includes connected straight tubes joined in bundles and arranged in parallel.

15. A system as recited in claim 4 , wherein the at least one tube includes connected straight tubes joined in bundles and arranged in parallel.

16. A system as recited in claim 3 , wherein the storage volume comprises a tube in a coil.

17. A system as recited in claim 4 , wherein the storage volume comprises a tube in a coil.

18. A method for storing and recovering energy from compressed air, water and water vapor in at least one tube providing a storage volume for the compressed air, water and water vapor, the tube being confined in a sealed pressurized pressure-resistant thermally-insulated tank, means for storing and releasing heat in the compressed air, water and water vapor stored in the tube and the compressed air including water and water vapor comprising:

a) compressing the air, water and water vapor;

b) storing the compressed air, water and water vapor in the storage volume; and

c) expanding the compressed air from within the storage volume to generate energy; and wherein

the water during energy storage progressively vaporizes until a water-vapor medium in phase equilibrium occurs which depends on pressure and temperature in the tank.

19. A method as recited in claim 18 comprising:

heating the compressed air prior to performing step c).

20. A method as claimed in claim 18 , comprising:

generating electrical energy with at least one turbine.