Thermodynamic system for storing/producing electrical energy

1. A system for producing and storing electrical energy, comprising a thermally insulated chamber containing a first closed circuitry in which circulates a first working fluid, a hot source through which a first leg of the first circuitry passes for a heat exchange between the first working fluid and the hot source, a cold source through which a second leg of the first circuitry passes for a heat exchange between the first working fluid and the cold source, the hot and cold sources being thermally insulated from each other, the first circuitry further comprising third and fourth legs connecting in series the first and second legs, the third leg comprising a first member for circulating the first working fluid in liquid phase and the fourth leg comprising a second member for circulating the first working fluid in gas phase, wherein the hot source is composed of a pure water ice slurry always at 0° C., the cold source is composed of an ice slurry with a temperature lower than or equal to −40° C. and the system for producing/storing electrical energy further comprises a second circuitry for circulating a second working fluid between the hot source and a constant temperature system outside the thermally insulated chamber, the constant temperature system being selected from the group comprising ambient air, a water reserve, a water stream, a water course, a waterway, wherein the second working fluid is circulated between said constant temperature system and the hot source by an auxiliary expansion valve and an auxiliary compressor, and is caused to exchange heat with the constant temperature system and the hot source; and,

wherein the system further comprises an intermediate temperature source at an intermediate temperature between the temperature of the hot source and the temperature of the cold source, and comprises an intermediate fluid circuitry carrying an intermediate working fluid, said intermediate fluid circuitry passing through and exchanging heat with the hot source, the cold source, and the intermediate temperature source, the intermediate temperature source being connected to the intermediate fluid circuitry in parallel to the hot source, by a first sub-leg equipped with a first compressor and a second sub-leg equipped with an first expansion valve, and the intermediate temperature source being connected to the intermediate fluid circuitry in parallel to the cold source, by a third sub-leg equipped with a second compressor and a fourth sub-leg equipped with an second expansion valve.

2. The system according to claim 1 , wherein the intermediate temperature source is made of an ice slurry at a temperature between −15° C. and −30° C.

3. The system according to claim 2 , wherein the intermediate temperature source is made of an ice slurry at a temperature of −21° C.

4. The system according to claim 1 , wherein the first working fluid and the intermediate working fluid are the same working fluid that circulates in the first circuitry and the intermediate fluid circuitry which form a single closed circuit.

5. The system according to claim 1 , wherein the first circuitry and the intermediate fluid circuitry are independent.

6. The system according to claim 1 , wherein the first fluid circulating member is a reversible pump, and the second circulating member is a reversible turbine.

7. The system according to claim 1 , wherein a low temperature regenerator is arranged to enable a heat exchange between the third and fourth legs connected to the cold source.

8. The system according to claim 1 , wherein a high temperature regenerator is arranged between portions of the fourth leg entering and exiting the second circulating member.

9. The system according to claim 1 , wherein a superheating member providing an external heat is provided on the first fluid circuitry immediately upstream of an input of the second circulating member in the electricity production mode of the second circulating member.