Process and system for the production of electrical energy from oxygenated carbon fuels, implementing solid oxide fuel cells (SOFCs)

Abstract

A process for producing electrical energy from an oxygenated carbon fuel, employing a reforming reactor (34) and a solid oxide fuel cell (SOFC) (40) comprising an anode (40a), a cathode (40c), and a stack (40b) between said anode (40a) and said cathode (40c), comprising the steps of: - reforming said oxygenated carbon fuel and water in the reforming reactor (34) to produce synthesis gas, - injecting the synthesis gas into the anode (40a) and combustion air into the cathode (40c) respectively, to react said synthesis gas with said air, in order to generate an electrical voltage between the anode (40a) and the cathode (40c), - recirculating the unreacted synthesis gas from the SOFC (40) into the catalytic burner (33) to provide the heat required for the next step. reforming in the reforming reactor (34), - heating the synthesis gas to be injected into the anode (40a),In order to reach a predetermined temperature level, the variation between the pressure inside the cathode (40c) and the anode (40a) is regulated within a predetermined pressure variation range. Figure 1,

Description

Title of the invention: Method and system for producing electrical energy from oxygenated carbon fuels, using solid oxide fuel cells (SOFCs) Field of the invention

[0001] The invention generally relates to a method for producing electrical energy from oxygenated carbon fuels, using solid oxide fuel cells (SOFCs). It also relates to a system implementing such a method. State of the art

[0002] A fuel cell system can refer to a configuration of one or more fuel cells configured to produce electrical power. Individual fuel cells, such as ceramic oxide fuel cells, can be arranged to form fuel cell stacks. A fuel cell stack can refer to a plurality of individual fuel cells electrically connected in series. The number of individual fuel cells that make up a given fuel cell system can depend on the amount of electrical power that the given fuel cell system is intended to produce. Alternatively, a fuel cell system can also include any other configuration of individual fuel cells, as described in EP 2258017 Bl.

[0003] The current-voltage characteristics of fuel cells depend, for example, on the reactant compositions, mass flow rate, temperature, and pressure. The electrochemical reactions in the fuel cell respond rapidly to fluctuations in the fuel cell load. However, the response capacity of the reactant input system is usually much slower, resulting in response times of a few seconds or even a few minutes. Attempting to obtain a higher efficiency from the fuel cells than the reactant input allows results in a weakening of the fuel cell voltage, potentially leading to irreversible damage to the fuel cells.Furthermore, load variations lead to rapid temperature changes within the fuel cell, which, particularly at high temperatures, cause detrimental thermomechanical stresses, resulting in a significant reduction in fuel cell performance and lifespan. Fuel cell systems must therefore be designed so that the load on each fuel cell is kept as constant as possible. that any variation in load is as controllable as possible, as described in document EP 2377226 Bl.

[0004] Fuel cell systems typically operate using gaseous fuel sources such as hydrogen, ammonia, natural gas, or biogas. These fuel sources require gas compression for storage or a complex piping infrastructure for gas delivery, with the added risk of leaks and greenhouse gas emissions. Other systems using liquid fuel sources are highly hazardous to humans, such as methanol, which can cause blindness if ingested in quantities as small as 10 ml.

[0005] Document WO 2023155996 A1 describes a process for producing electrical energy in a stationary, self-contained situation, using a chemical fuel obtained from an organic source, comprising steps for: reforming the chemical fuel to produce a synthesis gas, injecting said synthesis gas into a high-temperature fuel cell to produce electrical energy, said fuel cell comprising a plurality of stacks, processing said electrical energy to generate a nominal electrical energy adapted to the voltage and current required by the consumer, storing in a storage unit a portion of the electrical energy not used by the consumer.The process further includes a step for managing the stacks so that some of them are deactivated according to the required production level while others are kept operational and / or used to heat said deactivated stacks.

[0006] The anodic electrode of a solid oxide fuel cell (SOFC) typically contains considerable amounts of nickel, which is susceptible to forming nickel oxide if the atmosphere is not reducing. If significant nickel oxide formation occurs, the electrode morphology is irreversibly altered, leading to a substantial loss of electrochemical activity and potentially even cell failure. Therefore, SOFC systems require a safety gas containing reducing agents (such as hydrogen diluted with an inert element like nitrogen) during startup and shutdown to prevent oxidation of the fuel cell's anodic electrodes.

[0007] Oxidation of the anodes can be prevented by maintaining a reducing atmosphere in the anodic flow channels. Reducing conditions can be maintained by supplying fuel or other reducing species, such as a hydrogen-containing gas, at a sufficient velocity to reduce all the oxygen reaching the anodes. If the reducing gas has a high hydrogen (or hydrogen equivalent) content, the required flow rates are relatively low, and if ordinary fuel can be used, no additional gas source is necessary. By taking appropriate process and safety measures, ordinary fuel can be used to maintain a reducing atmosphere at the anodes during normal operations as well as during controlled start-up and shutdown.

[0008] However, in the event of an emergency shutdown (ESD) due, for example, to a gas alarm, all combustible gas supplies must be immediately interrupted. If hydrogen is still required at the anodes, it must be supplied as a diluted mixture with a hydrogen content sufficiently low so as not to form an explosive mixture with air in any mixing proportions.

[0009] According to prior art requirements, the quantity of operating reagents during a normal start-up or shutdown is minimized by anode recirculation, i.e., by recirculating the unused safety gas in the loop. This is because it is simultaneously necessary to minimize both the operating reagents and the heating time during start-up, and also simultaneously necessary to minimize both the operating reagents and the system cooling during shutdown. It is also possible to minimize the heating time during start-up in this recirculation process, because heat can also be recirculated in the process along with the unused gas. However, in the event of an emergency shutdown (ESD) due, for example, to a gas alarm or a power failure, no active recirculation will be available, which will increase the quantity of safety gas required.Furthermore, the cathodic airflow does not cool the system during ESD, as the air blower must be stopped, and the amount of safety gas required is therefore even higher, as the time required to cool the system to temperatures where nickel oxidation does not occur is even tripled compared to an active shutdown situation.

[0010] US patent 2002 / 028362 describes methods for protecting against anode oxidation in a high-temperature fuel cell system during shutdowns or fuel loss events. A reducing atmosphere is maintained around the anode of a molten carbonate or solid oxide fuel cell by controlling the electrical potential generated by the fuel cell and applying an external electrical potential to the fuel cell terminals, such that the electric current flows through the fuel cell in the opposite direction to the current flow during normal fuel cell operation, whenever the fuel cell output voltage drops below a predetermined level. An external power source is applied after such drops have reached the predetermined voltage level, which, in practice, is a voltage level significantly low. At least at lower operating temperatures, these embodiments fail to prevent oxidation of the anode.

[0011] US2005 / 095469 Al describes embodiments of applying a voltage across the terminals of high-temperature fuel cells, resulting in a current in the opposite direction to that of normal operation, thus preventing oxidation of the anodes.

[0012] Document EP 2727179 B1 describes an arrangement for minimizing the need for safety gas in a high-temperature fuel cell system, each fuel cell in the fuel cell system includes an anode side, a cathode side, and an electrolyte between the anode side and the cathode side, the fuel cells being arranged in fuel cell stacks, and the fuel cell system including fuel cell system piping for reactants, and means for supplying fuel to the anode sides of the fuel cells.

[0013] The objective of the present invention is to provide an alternative to prior art solutions (whether gaseous or electrical) that would be fully integrated into the overall energy system and would not require the installation of valves in hot zones. The main objective of the invention is therefore to provide a method and system for generating electrical energy that can be dynamically controlled and that resolves the pressure sensitivity between the anode and the cathode. Other objectives of the present invention are to eliminate carbon bonds in carbonaceous fuels, more preferably ethanol, before they enter the SOFC, in order to achieve high electrical efficiency and to ensure the protection of the anode using synthesis gas. Summary of the invention

[0014] This objective is achieved through a process for producing electrical energy from oxygenated carbon fuels, more preferably an ethanol-based fuel, by implementing a reforming reactor and a solid oxide fuel cell (SOFC) comprising an anode, a cathode and a stack between said anode and said cathode, and comprising the steps of:

[0015] - reform said oxygenated carbon fuel and water in said reactor of reforming, in order to produce synthesis gas,

[0016] - injecting said synthesis gas respectively into said anode and a supply in air in said cathode, to cause said synthesis gas to react electrochemically with said air, in order to generate an electrical voltage between said anode and said cathode,

[0017] - recirculating the unreacted synthesis gas from said SOFC into a oxidation reactor, in order to provide the heat necessary for said reforming step for said reforming reactor,

[0018] characterized in that it further comprises the steps of:

[0019] - heat the synthesis gas to be injected into said anode, to reach a level of predetermined temperature inside said anode, and

[0020] - regulate the variation between the pressure inside said cathode and the pressure at the inside of said anode within a predetermined pressure variation range.

[0021] The synthesis gas heating step can advantageously be implemented before the activation of the current in the SOFC and / or after the deactivation of the current in the SOFC, the recirculation step and the synthesis gas heating step being implemented in the SOFC.

[0022] The method of the invention may further include a step of cooling the air circulating in the cathode after the deactivation of the current in the SOFC.

[0023] The process of the invention may further include a step of heating the air to be injected into the cathode, to reach the predetermined temperature level.

[0024] It may further include the steps of:

[0025] - convert respectively said oxygenated carbon fuel and water from the state liquid in a gaseous state,

[0026] - to heat said oxygenated fuel and water in gaseous form respectively before putting them into the said reforming reactor.

[0027] In a particular embodiment of the invention, the process of the invention may also further comprise the step of reacting the excess syngas outside the anode and with a dedicated air supply, to provide heat to said reforming reactor, and a temperature control step in the reforming reactor, said temperature control step comprising:

[0028] - the detection of the temperature respectively inside the reforming reactor and inside a catalytic burner to heat the water in gaseous form before its injection into said reforming reactor, in order to provide temperature measurements,

[0029] - the processing of said temperature measurements to regulate an air flow of combustion supplied by the catalytic burner.

[0030] Oxygenated carbon fuels may include alcohols, ketones, ethers, organic acids, preferably ethyl alcohol or ethanol.

[0031] The process of the invention may also further include a step of regulating the flow of the supplementary oxygenated fuel supplied to the catalytic burner.

[0032] According to another aspect of the invention, a system for producing electrical energy from said fuel is proposed, implementing the process according to the invention, comprising:

[0033] - a reactor intended to reform said oxygenated carbon fuel and water, in order to to produce synthesis gas,

[0034] - a solid oxide fuel cell (SOFC) comprising an anode, a cathode and a stacking between said anode and said cathode,

[0035] - means for injecting said synthesis gas into said anode,

[0036] - means for injecting a supply of air into said cathode,

[0037] - means for recirculating unreacted synthesis gas from said SOFC in a reforming reactor, in order to provide the heat necessary for said reforming reactor,

[0038] - means for injecting the oxygenated carbon fuel into said burner catalytic in order to produce additional heat,

[0039] characterized in that it further comprises:

[0040] - means for heating the synthesis gas to be injected into said anode, in order to to reach a predetermined temperature level, and

[0041] - a loop for regulating the variation between the pressure inside said cathode and the pressure inside said anode within a predetermined pressure variation range.

[0042] The loop for regulating the pressure variation may advantageously include at least one pressure regulating valve arranged at an exhaust air outlet from the cathode and / or at a combustion gas outlet from the anode.

[0043] The energy production system according to the invention may further include a three-way valve provided to selectively direct all or part of the inlet air to be injected into the cathode either (i) directly, or (ii) via one or more heat exchangers arranged to heat said inlet air.

[0044] The means for heating the synthesis gas can advantageously be activated before the activation of the current in the SOFC and / or after the deactivation of the current in the SOFC.

[0045] The production system of the invention may further include means for heating the air to be injected into the cathode, to reach the predetermined temperature level.

[0046] The system of the invention may also further comprise means for:

[0047] - convert respectively said oxygenated carbon fuel and water from the state liquid in a gaseous state,

[0048] - to heat said oxygenated carbonaceous fuel and water respectively in the form gaseous before they are introduced into the said reforming reactor,

[0049] - means for reacting the excess synthesis gas outside the anode with a dedicated air supply, to the catalytic burner to provide heat to the reforming reactor,

[0050] - a loop for temperature regulation in the reforming reactor, said temperature control loop including:

[0051] - means for detecting the temperature respectively inside the reforming reactor and within a unit designed to heat water in gaseous form before its injection into said reforming reactor, in order to provide temperature measurements,

[0052] - means for processing said temperature measurements,

[0053] - means for regulating the flow of combustion air supplied to said unit heated.

[0054] The system of the invention may also further comprise: - means of regulating the flow rate of the supplementary oxygenated carbonaceous fuel (52) supplied to the catalytic burner (33), - a catalytic steam reforming reactor (64) intended to convert oxygenated carbon fuel into heated synthesis gas. Oxygenated carbon fuel may include bio-based oxygenated carbon which may include bio-based ethanol. Description of the drawings

[0055] - [Fig. 1] Fig. 1 is a schematic view of a first embodiment of a SOFC-based electrical power generation system according to the invention; and

[0056] - [Fig.2] Fig.2 is a schematic view of a second embodiment of a SOFC-based electrical power generation system according to the invention. Detailed description

[0057] The components common to the two embodiments shown in Figures 1 and 2 are indicated by common reference numbers.

[0058] With reference to [Fig.1] representing a first embodiment of the invention, a system SI according to the invention for producing electrical energy from an oxygenated carbon fuel comprises a solid oxide fuel cell (SOFC) 40 provided with an anode 40a, a stack 40b and a cathode 40c, and a reforming reactor 34, each being respectively included in a thermal test box 50.

[0059] The IS system comprises:

[0060] - a fuel inlet 1 intended to receive an oxygenated carbonaceous fuel, for example ethanol, coming from a fuel tank (not shown),

[0061] - an air supply for SOFC 10 intended to receive air as an oxidant for SOFC 40,

[0062] - an air inlet 8 intended to receive air as an oxidant for a burner catalytic converter 33 upstream of the reforming reactor 34,

[0063] - a water supply 6 intended to receive water to be treated as a reagent by reforming reactor 34,

[0064] - an electrical output (not shown) of the SOFC 40, intended to provide electrical energy at a conversion unit (not shown),

[0065] - an exhaust air outlet 15 intended to extract exhaust air from of the 40c cathode,

[0066] - an exhaust outlet 18 intended to extract exhaust gases (gases of combustion) from the catalytic burner 33 and the SOFC 40.

[0067] The ethanol-based fuel entering through inlet 1 is permitted:

[0068] - via a pipe 2 to an electric evaporation unit 30 which distributes gaseous oxygenated carbon via pipe 3 to the catalytic burner 33, which distributes heated gaseous oxygenated carbon via pipe 19 as an input to the reforming reactor 34.

[0069] - via a pipe 4 to an electric evaporator and a heat exchanger heat 31 which distributes via a pipe 5 heated gaseous oxygenated carbon as an input into the reforming reactor 34.

[0070] Air from the SOFC 10 air supply enters a three-way valve 54 which selectively distributes this air (i) either via a pipe 49 to a first heat exchanger 32 supplying a third heat exchanger 36 connected via a pipe 12 to a fourth heat exchanger 38 supplying the cathode 40c, or (ii) directly via a heating device 51 to said fourth heat exchanger 38.

[0071] The catalytic burner 33 has a catalytic surface which helps to burn the oxygenated carbon fuel.

[0072] The fifth heat exchanger 37 is intended to balance the temperature between the anode 40a and the cathode 40c.

[0073] In a specific embodiment of the invention, this heat exchanger is optional and the anode and cathodes are directly connected respectively to pipes 22 and 12.

[0074] The three-way valve 54 is intended to selectively cool or heat the air inside the cathode 40c of the SOFC 40.

[0075] The exhaust air exiting the cathode 40c passes through a pipe 13 and through the third heat exchanger 36 to an electric evaporator and a heat exchanger 39. The heat from this exhaust air 15 is therefore transferred to the liquid water from the water supply 6, said incoming liquid water being transformed into water in gaseous or vapor form. The water in gaseous form exiting the electric evaporator and heat exchanger 39 is transferred via a pipe 7 to the catalytic burner 33 to be heated before being injected into the reforming reactor 34 via a pipe 16. The reforming reactor 34 distributes a synthesis gas which is transferred via a pipe 21 to a second heat exchanger 35 from which the heated synthesis gas is introduced via a pipe 22 into the fourth heat exchanger 38 which feeds the anode 40a of the SOFC 40.

[0076] The unreacted synthesis gas exiting the anode 40a is transferred via a pipe 23 to the second heat exchanger 35 intended to transfer the heat of said unreacted synthesis gas to the synthesis gas distributed by the reforming reactor 34.

[0077] Downstream of the second heat exchanger 35, the unreacted syngas passes through a pipe 24 through the electric evaporator and the heat exchanger 31 and through a pipe 25 through the first heat exchanger 32 intended to transfer the heat of said unreacted syngas to the air from the SOFC 10 air supply when the three-way valve is controlled for heating the airflow.

[0078] The unreacted synthesis gas downstream of the first heat exchanger 32 is then transferred via a pipe 26 and via the catalytic burner 33 to the reforming reactor 34, which receives oxygenated carbon vapor and emits a combustion gas that passes via a pipe 53 through a fourth heat exchanger 38 designed to transfer the heat from said combustion gas to the combustion air from the combustion air supply 8. Said heated combustion air is transferred via a heating device 47 and a pipe 9 to the catalytic burner 33. The combustion gas outlet 18 downstream of the sixth heat exchanger 39 is regulated by a first pressure regulating valve 48, which regulates the pressure of the anode 40a of the SOFC 40, while a second pressure regulating valve 52 regulates the pressure of the exhaust air distributed by the SOFC 40 cathode 40c.The two pressure regulating valves 48, 52 are controlled so as to maintain a pressure variation between the cathode 40c and the anode 40a within a predetermined range, for example between -10 mbar and +10 mbar.

[0079] With reference to [Fig. 2] representing a second embodiment of the invention, a system S2 according to the invention intended to produce electrical energy from a oxygenated carbon fuel includes a solid oxide fuel cell (SOFC) 40 provided with an anode 40a, a stack 40b and a cathode 40c, and a catalytic steam reforming reactor 64, each respectively included in a thermal test box 60.

[0080] The S2 system comprises:

[0081] - a fuel inlet 1 intended to receive an oxygenated carbonaceous fuel, for example ethanol, coming from a fuel tank (not shown),

[0082] - an air supply for SOFC 10 intended to receive air as an oxidant for SOFC 40,

[0083] - an air inlet 8 intended to receive air as an oxidant for the reactor catalytic steam reforming 64,

[0084] - a water supply 6 intended to receive water to be treated as a reagent by the catalytic steam reforming reactor 64,

[0085] - an electrical output (not shown) of the SOFC 40, intended to provide electrical energy at a conversion unit (not shown),

[0086] - an exhaust air outlet 15 intended to extract exhaust air from of the 40c cathode,

[0087] - an exhaust outlet 18 intended to extract exhaust gases (gases of combustion) from reforming reactor 64 and SOFC 40.

[0088] The ethanol-based fuel entering through inlet 1 is permitted:

[0089] - via a pipe 2 to an electric evaporation unit 30 which distributes gaseous oxygenated carbon via pipe 3 to the catalytic steam reforming reactor 64,

[0090] - via a pipe 4 to an electric evaporator and a heat exchanger heat 31 which distributes via a pipe 5 heated gaseous oxygenated carbon as an input into the catalytic steam reforming reactor 64.

[0091] Air from the SOFC 10 air supply enters a three-way valve 54 which selectively distributes this air (i) either through a pipe 49 to a first heat exchanger 32 supplying a third heat exchanger 36 connected through a pipe 12 to a fourth heat exchanger 38 supplying the cathode 40c, or (ii) directly through a heating device 51 to said fourth heat exchanger 38.

[0092] As in the embodiment of [Fig.1], the three-way valve 52 is provided to selectively cool or heat the air inside the cathode 40c of the SOFC 40.

[0093] The exhaust air exiting the cathode 40c passes through a pipe 13 and through the third heat exchanger 36 to an electric evaporator and a heat exchanger Heat 39 is transferred via a pipe 14. The heat from this exhaust air 15 is thus transferred to the liquid water from the water supply 6, said incoming liquid water being transformed into water in gaseous or vapor form. The exhaust air downstream of the electric evaporator and the heat exchanger 39 is regulated by a pressure regulating valve 52 before leaving the system S2 as exhaust air 15.

[0094] The water in gaseous form exiting the electric evaporator and heat exchanger 39 is transferred via a pipe 7 to the catalytic steam reforming reactor 64.

[0095] The catalytic steam reforming reactor 64 distributes a synthesis gas which is transferred via a pipe 21 to a second heat exchanger 35 from which the heated synthesis gas is introduced via a pipe 22 into the fourth heat exchanger 38 which feeds the anode 40a of the SOFC 40.

[0096] The unreacted synthesis gas exiting the anode 40a is transferred via a pipe 23 to the second heat exchanger 35 provided to transfer the heat of said unreacted synthesis gas to the synthesis gas distributed by the catalytic steam reforming reactor 64.

[0097] Downstream of the second heat exchanger 35, the unreacted syngas passes through a pipe 24 through the electric evaporator and the heat exchanger 31 and through a pipe 25 through the first heat exchanger 32 intended to transfer the heat of said unreacted syngas to the air from the SOFC 10 air supply when the three-way valve is controlled for heating the airflow.

[0098] The unreacted synthesis gas downstream of the first heat exchanger 32 is then transferred via a pipe 26 into the catalytic steam reforming reactor 64 which receives oxygenated carbon vapor and emits a combustion gas which passes through a pipe 53 through a fourth heat exchanger 38 provided to transfer the heat of said combustion gas to the combustion air from the combustion air supply 8, said heated combustion air being transferred via a heating device 47 and a pipe 9 to the catalytic burner 33.

[0099] The combustion gas outlet 18 downstream of the sixth heat exchanger 39 is regulated by another pressure regulating valve 48 which regulates the pressure of the anode 40a of the SOFC 40, while the pressure regulating valve 52 regulates the exhaust air pressure distributed by the cathode 40c of the SOFC 40.

[0100] With these two embodiments of the method and system according to the invention described above, it is then possible to guarantee total reliability of the SOFC in the respective activation and deactivation phases during which there is no electrical activity inside the SOFC stacks, thanks to the regulation of the pressure variation inside the cathode and anode of the SOFC as well as the use of a three-way valve used to heat or cool the air injected into the cathode.

[0101] During a start-up phase of an energy production system SI, S2 according to the invention, the three-way valve 54 is controlled so as to heat the SOFC to a temperature level required to allow energy conversion within the SOFC, usually around 500 °C, while the pressure variation between the cathode and the electrode is controlled using the two pressure regulating valves 48, 52.

[0102] The three-way valve 54 is controlled during the heating phase to heat the air with an electric heating device 51.

[0103] The electric heating devices 30, 31, 39, 51 can be replaced by other means of heating, for example heat exchangers or burners.

[0104] The heating devices 31, 39, 51 are used during heating. After heating and during energy production, the heating devices 31, 39 are used solely as heat exchangers.

[0105] Of course, the present invention is not limited to the embodiments described above and many other embodiments can be devised without departing from the scope of the invention.

Claims

Demands

1. A method for producing electrical energy from an oxygenated carbon fuel, employing a reforming reactor (34, 64) and a solid oxide fuel cell (SOFC) (41) comprising an anode (40a), a cathode (40c) and a stack (40) between said anode (40a) and said cathode (40c), comprising the steps of: - reforming said oxygenated carbon fuel and water in said reforming reactor (34, 64), in order to produce a synthesis gas, - injecting said synthesis gas into said anode (40a) and combustion air into said cathode (40c), respectively, to react said synthesis gas with said air, in order to generate an electrical voltage between said anode (40a) and said cathode (40c), - recirculating the unreacted synthesis gas from said SOFC (41) into said reforming reactor (34, 64), in order to provide the heat necessary for said reforming,characterized in that it further comprises the steps of: - heating the synthesis gas to be injected into said anode (40a), to reach a predetermined temperature level inside said anode (40a), and - regulating the variation between the pressure inside said cathode (40c) and the pressure inside said anode (40a) within a predetermined pressure variation range.

2. A method according to the preceding claim, wherein the syngas heating step is carried out before the current is activated in the SOFC, said recirculation step and said syngas heating step being carried out in said SOFC.

3. A method according to any one of the preceding claims, wherein the syngas heating step is carried out after the current is switched off in the SOFC, said recirculation step and said syngas heating step being carried out in said SOFC.

4. Method according to the preceding claim, further comprising a step of cooling the air circulating in the cathode after the deactivation of the current in the SOFC.

5. A method according to any one of the preceding claims, further comprising a step of heating the air to be injected into the cathode (40c), to reach the predetermined temperature level.

6. A method according to any one of the preceding claims, further comprising the steps of: - converting said oxygenated carbon fuel and water respectively from the liquid state to the gaseous state, - heating said oxygenated carbon fuel and water respectively in gaseous form before introducing them into said reforming reactor (34).

7. A method according to any one of the preceding claims, further comprising the step of reacting the excess synthesis gas from the anode (40a) with air from a dedicated air supply, in order to provide heat to the reforming reactor (34).

8. A method according to any one of the preceding claims, further comprising a temperature control step in the reforming reactor (34), said temperature control step comprising: - sensing the temperature respectively inside the reforming reactor (34) and inside a catalytic burner (33) to heat the water in gaseous form before its injection into said reforming reactor (34), in order to provide temperature measurements, - processing said temperature measurements to regulate a combustion air flow supplied to said catalytic burner (33).

9. Method according to the preceding claim, further comprising a step of regulating the flow of the supplementary oxygenated carbon fuel supplied to the catalytic burner (33).

10. System (SI, S2) for producing electrical energy from an oxygenated carbon fuel, implementing the process according to any one of the preceding claims, comprising: - a reactor (34, 64) for reforming said oxygenated carbon fuel and water, in order to produce a synthesis gas, - a solid oxide fuel cell (SOFC) (40) comprising an anode (40a), a cathode (40c) and a stack (40b) between said anode (40a) and said cathode (40c), - means for injecting said synthesis gas into said anode (40a), - means for injecting a supply of combustion air into said cathode (40c), - means for recirculating the unreacted synthesis gas from said SOFC (40) into a reforming reactor (34, 64), in order to provide the heat necessary for said reforming reactor (34), characterized in that it further comprises: - means (35) for heating the synthesis gas to be injected into said anode (40a), in order to reach a predetermined temperature level, and - a loop (48, 52) for regulating the variation between the pressure inside said cathode (40c) and the pressure inside said anode (40a) within a predetermined pressure variation range.

11. System (SI, S2) according to the preceding claim, wherein the pressure variation control loop comprises at least one pressure control valve (52, 48) disposed at an outlet (15) of the exhaust air from the cathode (40c) and / or at an outlet (18) of the combustion gas from the anode (40a).

12. System (SI, S2) according to any one of the two preceding claims, further comprising a three-way valve provided for selectively directing all or part of the inlet air to be injected into the cathode (40c) either (i) directly, or (ii) via one or more heat exchangers arranged to heat said inlet air.

13. System (SI, S2) according to any one of claims 10 to 12, wherein the synthesis gas heating means (35) are activated before the activation of the current in the SOFC (40).

14. System (SI, S2) according to any one of claims 10 to 13, further comprising means (32, 36) for heating the air to be injected into the cathode (40c), to reach the predetermined temperature level.

15. System (SI) according to any one of claims 10 to 14, further comprising: - means (33) for converting said oxygenated carbon fuel and water from the liquid state to the gaseous state, - means intended to heat said oxygenated carbon fuel and water in gaseous form respectively before introducing them into said reforming reactor (34).

16. System (SI) according to claims 10 to 15, further comprising means (33) for reacting excess synthesis gas outside the anode (40a) with a dedicated air supply, in order to provide heat to the reforming reactor (34).

17. System according to the preceding claim, further comprising means for regulating the flow of the supplementary oxygenated carbon fuel (52) supplied to the catalytic burner (33).

18. System (S2) according to any one of claims 10 to 14, further comprising a catalytic steam reforming reactor (64) for converting oxygenated carbon fuel into heated synthesis gas.

19. System according to any one of claims 10 to 18, wherein the oxygenated carbon fuel comprises bio-based oxygenated carbon.

20. System according to the preceding claim, wherein the bio-based oxygenated carbon fuel comprises bio-based ethanol.

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