Plant and process for energy generation and storage

A process for energy generation and storage, comprising:

• carrying out a closed cyclic thermodynamic transformation through a working fluid different from atmospheric air;
• the closed thermodynamic cyclic transformation being carried out first in one direction in a charge phase and then in an opposite direction in a discharge phase;
• the closed thermodynamic cyclic transformation being carried out between a casing and a tank;
• wherein, in the charge phase, the working fluid stored in the casing in a gaseous phase and in pressure equilibrium with the atmosphere, is compressed, cooled and stored in the tank in a liquid or supercritical phase with a temperature close to the critical temperature;
• wherein, in the charge phase, the process accumulates heat and pressure;
• wherein the charge phase comprises:
• compressing in a compressor said working fluid coming from said casing, the casing being externally in contact with the atmosphere and delimiting at the interior thereof a volume configured to contain the working fluid at atmospheric pressure or substantially atmospheric, wherein energy is absorbed while compressing the working fluid;
• introducing the compressed working fluid through a primary heat exchanger and a secondary heat exchanger placed in series to bring a temperature of the working fluid close to its own critical temperature;
• wherein the primary heat exchanger works as a cooler to remove heat from the compressed working fluid, cool the compressed working fluid and store thermal energy, wherein the secondary heat exchanger works as a cooler to remove further heat from the compressed working fluid and store further thermal energy;
• and
• accumulating the cooled working fluid in said tank;
• wherein the secondary heat exchanger and the primary heat exchanger carry out a super-critical transformation of the working fluid so that said working fluid is accumulated in the tank in the super- critical phase or wherein the secondary heat exchanger and the primary heat exchanger carry out a sub-critical transformation of the working fluid so that said working fluid is accumulated in the tank in the liquid phase;
• wherein, in the discharge phase, the working fluid stored in the tank in the liquid or supercritical phase is heated, expanded and returned to the casing in the gaseous phase and in pressure equilibrium with the atmosphere;
• wherein, in the discharge phase, the process generates energy;
• wherein the discharge phase comprises:
• passing the working fluid, coming from the tank, through the secondary heat exchanger and the primary heat exchanger;
• wherein the secondary heat exchanger works as a heater to transfer heat to the working fluid coming from the tank, wherein the primary heat exchanger works as a heater to transfer further heat to the working fluid and heat the working fluid;
• passing the heated working fluid through a turbine, wherein the turbine is rotated by the heated working fluid and drives at least one of a generator and a driven machine, generating energy, wherein the working fluid expands and cools down in the turbine;
• and
• re-introducing the working fluid coming from the turbine into the casing at the atmospheric or substantially atmospheric pressure;
• wherein the process further comprises:
• carrying out, with at least a part of said working fluid, a closed thermodynamic cycle in a closed circuit;
• and
• wherein the process further comprises:
• increasing the pressure in the discharge phase by means of a pump placed between the secondary heat exchanger and the primary heat exchanger.

A process for energy generation and storage, comprising:

• carrying out a closed cyclic thermodynamic transformation through a working fluid different from atmospheric air;
• the closed thermodynamic cyclic transformation being carried out first in one direction in a charge phase and then in an opposite direction in a discharge phase;
• the closed thermodynamic cyclic transformation being carried out between a casing and a tank;
• wherein, in the charge phase, the working fluid stored in the casing in a gaseous phase and in pressure equilibrium with the atmosphere, is compressed in a compressor, cooled through a primary heat exchanger and a secondary heat exchanger working as coolers and stored in the tank in a liquid or supercritical phase with a temperature close to the critical temperature;
• wherein, in the charge phase, the process accumulates heat and pressure and the primary heat exchanger and secondary heat exchanger store thermal energy;
• wherein, in the discharge phase, the working fluid stored in the tank in the liquid or supercritical phase is heated through the primary heat exchanger and the secondary heat exchanger working as heaters, expanded in a turbine and returned to the casing in the gaseous phase and in pressure equilibrium with the atmosphere;
• wherein, in the discharge phase, the process generates energy through the turbine;
• wherein the process further comprises:
• carrying out, with at least a part of said working fluid, a closed thermodynamic cycle in a closed circuit;
• wherein the closed circuit for actuation of the closed thermodynamic cycle passes through:
• the compressor, a further heat exchanger, the turbine and an additional heat exchanger;
• and
• wherein the closed circuit comprises:
• a first bypass conduit connecting an outlet of the compressor with the further heat exchanger and bypassing the primary heat exchanger and the tank;
• a second bypass conduit connecting an outlet of the turbine with an inlet of the compressor and bypassing the casing.