Energy generation system and method thereof

1. An energy generation system for use in operating a heat engine, the system comprising:

a reduction unit energized by an external energy source and being configured and operable for reducing CO 2 into CO and O 2 , said CO 2 reduction unit having a gas inlet associated with a gas outlet of the heat engine for inputting CO 2 , and having CO and O 2 gas outlets, and

a combustor comprising a plurality of gas inlets including gas inlets connected to the outlets of said reduction unit for receiving the CO and O 2 gases, and a gas inlet for receiving a CO 2 working fluid, and a gas outlet connectable to a gas inlet of the heat engine, said combustor being configured and operable to cause a reaction between said CO and O 2 gases thereby combusting the CO gas to form CO 2 gas, and for supplying, through said gas outlet, a substantially pure CO 2 gas to drive the heat engine,

the energy generation system thereby providing operation of the heat engine driven by said external energy source via the reduction of CO 2 .

2. The energy generation system of claim 1 , wherein said combustor further comprises an additional inlet associated with said gas outlet of the heat engine and configured for receiving at least a portion of said CO 2 exhausted by the heat engine.

3. The energy generation system of claim 1 , further comprising a conduit that bypasses said combustor while conveying CO 2 directly to a gas inlet of the heat engine.

4. The energy generation system of claim 1 wherein the system is configured as combined cycle, wherein said combined cycle comprises a first cycle and a second cycle, said first cycle comprising a heat engine and said second cycle comprising a Rankine turbine.

5. The energy generation system of claim 1 , wherein the system is configured as a combined cycle, wherein said combine cycle comprises a first cycle and a second cycle, said second cycle comprises a heat recovery unit (HRU) connected to the heat engine outlet and having at least one CO 2 inlet and one CO 2 outlet, said HRU being configured and operable for transferring at least some heat from CO 2 exhausted by the heat engine to a fluid circulating in the second cycle.

6. The system of claim 1 , wherein:

said reduction unit is configured and operable for reducing a mixture of CO 2 and water or steam into O 2 and syngas (a mixture of CO and H 2 );

said combustor is configured and operable for reaction between syngas and O 2 yielding the mixture of CO 2 and water-steam; and

said heat engine is driven by the gas output from said combustor comprising said mixture of CO 2 and water-steam.

7. The energy generation system of claim 1 , wherein said reduction unit comprises:

a buffer storage module for receiving from an HRU, a fluid being CO 2 or a mixture of CO 2 and steam or water;

a reduction reactor configured and operable to receive said fluid from said buffer storage module and to reduce CO 2 into CO and O 2 or said mixture of CO 2 and steam or water into syngas and O 2 ;

a flow regulator regulating the fluid flow from said buffer storage module to said reduction reactor;

a first compressor configured and operable to compress CO or syngas leaving said reduction reactor and to supply compressed CO or syngas to said combustor, and a second compressor configured and operable to compress O 2 leaving said reduction reactor and to supply compressed O 2 to said combustor.

8. A power plant for generating electricity, comprising:

a steam cycle comprising a steam turbine having an inlet for receiving high-temperature steam and an outlet for exhausting stream and/or water having lower temperature and pressure than the high-temperature steam, the steam turbine being powered by passage of steam therethrough;

the energy generation system of claim 1 , for transferring at least some heat from said combustor's exhaust to said water and/or steam exhausted by said heat engine being a steam turbine, thereby powering said steam cycle and driving the steam turbine; and

an electric generator associated with said steam turbine and configured for using work generated by said steam turbine to generate electricity.

9. A method for use in operating a heat engine, the method comprising:

(a) reducing a CO 2 gas into CO and O 2 gases;

(b) reacting said CO and O 2 gases, thus combusting the CO gas, and yielding a substantially pure CO 2 outlet gas;

(c) supplying said CO 2 outlet gas to the heat engine as a working gas in its heat-to-work generation process.

10. The method of claim 9 , further comprising:

(d) directing CO 2 gas exhausted by the heat engine to a reduction unit for further reduction; and

(e) repeating the preceding steps;

whereby the method is configured to enable generating a closed-loop cycle of the heat engine operation by reusing the CO 2 exhausted from the heat engine to produce CO and O 2 .

11. The method of claim 9 , further comprising conveying CO 2 gas to a gas inlet of the heat engine, while bypassing a combustor wherein said CO is combusted to yield a substantially pure CO 2 outlet gas.

12. The method of claim 9 , wherein reducing CO 2 into CO and O 2 is performed by using additional CO 2 gas supplied from an external source.

13. The method of claim 9 , wherein:

a mixture of CO 2 and water or steam is reduced to syngas (a mixture of CO and H 2 ) and separated O 2 ;

syngas reacts with O 2 yielding a mixture of CO 2 and water;

said mixture of CO 2 and water or steam is supplied to the heat engine; and

the mixture of CO 2 and water or steam exhausted from the heat engine is directed to the said reduction unit for further reduction.