WO1999035702A1 - Power generation system utilizing turbine gas generator and fuel cell - Google Patents

Power generation system utilizing turbine gas generator and fuel cell Download PDF

Info

Publication number
WO1999035702A1
WO1999035702A1 PCT/US1998/000250 US9800250W WO9935702A1 WO 1999035702 A1 WO1999035702 A1 WO 1999035702A1 US 9800250 W US9800250 W US 9800250W WO 9935702 A1 WO9935702 A1 WO 9935702A1
Authority
WO
WIPO (PCT)
Prior art keywords
fuel cell
gas
stage
turbine
electricity
Prior art date
Application number
PCT/US1998/000250
Other languages
French (fr)
Inventor
Mark J. Skowronski
Original Assignee
Southern California Edison Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Southern California Edison Company filed Critical Southern California Edison Company
Priority to AU58168/98A priority Critical patent/AU5816898A/en
Priority to PCT/US1998/000250 priority patent/WO1999035702A1/en
Publication of WO1999035702A1 publication Critical patent/WO1999035702A1/en

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04082—Arrangements for control of reactant parameters, e.g. pressure or concentration
    • H01M8/04089—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants
    • H01M8/04111—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants using a compressor turbine assembly
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04007—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids related to heat exchange
    • H01M8/04014—Heat exchange using gaseous fluids; Heat exchange by combustion of reactants
    • H01M8/04022—Heating by combustion
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/10—Fuel cells with solid electrolytes
    • H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
    • H01M2008/1293—Fuel cells with solid oxide electrolytes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/14—Fuel cells with fused electrolytes
    • H01M2008/147—Fuel cells with molten carbonates
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2250/00—Fuel cells for particular applications; Specific features of fuel cell system
    • H01M2250/40—Combination of fuel cells with other energy production systems
    • H01M2250/402—Combination of fuel cell with other electric generators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0002—Aqueous electrolytes
    • H01M2300/0005—Acid electrolytes
    • H01M2300/0008—Phosphoric acid-based
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0017—Non-aqueous electrolytes
    • H01M2300/0048—Molten electrolytes used at high temperature
    • H01M2300/0051—Carbonates
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0017—Non-aqueous electrolytes
    • H01M2300/0065—Solid electrolytes
    • H01M2300/0068—Solid electrolytes inorganic
    • H01M2300/0071—Oxides
    • H01M2300/0074—Ion conductive at high temperature
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0017—Non-aqueous electrolytes
    • H01M2300/0065—Solid electrolytes
    • H01M2300/0082—Organic polymers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04007—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids related to heat exchange
    • H01M8/04014—Heat exchange using gaseous fluids; Heat exchange by combustion of reactants
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
    • H01M8/04701—Temperature
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
    • H01M8/04746—Pressure; Flow
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02B90/10—Applications of fuel cells in buildings
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E20/00—Combustion technologies with mitigation potential
    • Y02E20/16—Combined cycle power plant [CCPP], or combined cycle gas turbine [CCGT]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Definitions

  • the present invention is directed to a power generation system.
  • the electrical power originating from both the generator and the fuel cell form the output of the installation.
  • Difficulties associated with the Hendricks system are complexity and it has a high capital cost, in that it requires multiple turbines. Accordingly, there is a need for small scale power installation units that have high energy efficiency, have capital and operating costs comparable to those of large scale installations, and create minimum pollution.
  • the present invention is directed to a system for generating electricity that satisfies these needs.
  • the system comprises as its main components (i) a fuel cell, (ii) a heat exchanger, also referred to as a heating stage or recuperator, and (iii) an integral power generator.
  • the integral power generator comprises three units on a single shaft, namely a compressor, an electricity generator, and a turbine.
  • This system operates on fossil fuel, preferably natural gas, and inexpensively and cleanly generates electricity.
  • oxygen-containing gas typically air
  • Fuel and the compressed gas, serving as an oxygen source, are introduced into the fuel cell through an inlet, wherein the fuel is converted by oxidation to produce electricity, water, and hot a exhaust gas.
  • the electricity produced by the fuel cell is one source of electricity generated by this system.
  • Additional electricity is produced by the turbine generator. This electricity is obtained by taking the fuel cell exhaust gas and introducing it into an inlet of the turbine as a drive gas for driving the turbine, which in turn, because they are on the same shaft, drives the generator and the compressor.
  • the turbine operates at at least 50,000 RPM, and generally from about 70,000 to about 90,000 RPM.
  • the generator produces a high-frequency alternating current, typically at least 800 Hz, and generally from about 1 ,200 to about 1 ,600 Hz.
  • the power from the generator can be converted to direct current, and then combined with the direct current electricity from the fuel cell.
  • This combined direct current can then be inverted in an inverter to produce relatively low-frequency alternating current for consumption, typically having a frequency of 50 to 60 Hz.
  • Spent turbine drive gas once discharged from the turbine through an outlet, is used for heating the oxygen-containing gas fed to the fuel ceil in the heating stage by introducing spent turbine drive gas into an inlet of the heating stage.
  • the exhaust gas from the fuel cell may be at a higher temperature, i.e, about 1 800°F, than commercially available turbine power generators can operate, which is generally in the order of only about 1 600-1700 °F. Therefore, preferably, the turbine drive gas includes a sufficient quantity of compressed gas from the compressor to maintain the turbine drive gas at a sufficiently low temperature that it does not damage the turbine.
  • water be combined with the compressed air before it is introduced into the heat exchanger to maximize the heat recovery from the turbine exhaust gas.
  • the water used for this purpose can be water generated in the fuel ceil or from an independent source.
  • a power generator 10 comprising a compressor 12, an electrical generator 14, and a turbine 16, all sharing a common shaft 17;
  • a recuperator or regenerator 20 also referred to as a heating stage or heat exchanger
  • the power generation unit shown in the drawing has the compressor 12, the generator 14, and the turbine 16 mounted on the same shaft 17 in that sequential order, but that is not required.
  • the turbine 16 can be between the generator 14 and the compressor 12, or the compressor 12 can be between the generator 14 and the turbine 16.
  • a suitable power generator can be obtained from Capstone Turbine Corporation of Tarzana, California.
  • the Capstone power generator referred to has a turbine 16 which generates about 24 kW.
  • Another satisfactory power generation will be available from Allied Signal of Torrance, California, which has a turbine providing from about 40 to about 50 kW, and larger units are planned up to 200 kW.
  • the compressor 12 and the turbine 16, which turn on a common shaft with the generator 14 at high speed, can each or both be radial (centrifugal) design, or both can be an axial flow design.
  • the bearings required for the power generation unit 10 can be located on the shaft 17 with the generator 14 cantilevered on the shaft, or the generator 14 can be located between the bearings. Air bearings are preferred to reduce the complexity of the machine.
  • the high speed generator 14 uses a permanent magnet to supply the necessary magnetic lines of force.
  • the fuel cell 18 catalytically converts methane to hydrogen and carbon dioxide with heat generation; and the hydrogen is then combined with oxygen in an oxygen-containing gas to generate electricity, plus waste heat and water.
  • fuel cells are suitable for use in the system of the invention.
  • One type that can be used is a molten carbonate fuel cell.
  • a phosphoric acid fuel cell can be used.
  • a low-temperature fuel cell, such as a proton exchange membrane or phosphoric acid can be used, but with less efficiency.
  • the preferred fuel cell is a solid oxide fuel cell, which typically operates at a temperature from 1 600 to 1 800°F.
  • a solid oxide fuel cell can be obtained from Westinghouse, Pittsburgh, Pennsylvania.
  • the Westinghouse fuel cells can be obtained in any size, in 250 watt increments.
  • the heating stage 20 can be a fixed recuperator or a revolving regenerator.
  • the rectifier 22 is typically a diode system whose purpose is to convert high-frequency alternating current to direct current.
  • the purpose of the inverter 24 is to convert direct current to a low- frequency, alternating current, typically 50 to 60 Hz, for domestic use.
  • Table I provides the temperature, pressure, and flow rates of the various streams of the system shown in the drawing.
  • the inputs to the system are an oxygen-containing gas, typically air 32, and a fuel 34, which is typically natural gas, which is principally made up of methane.
  • the input air 32 is used for oxidizing the fuel 34 in the fuel cell, after it is compressed and heated.
  • the air 32 is first compressed in the compressor 12.
  • the compressed oxygen- containing gas 34 is then heated in the heating stage 26, to produce the heated, compressed, input oxygen-containing gas stream 37 for the fuel cell 18.
  • the oxygen-containing gas is typically air 32, it can be other gases containing oxygen, such as air partially depleted of oxygen, or air enriched with oxygen.
  • the outputs from the fuel cell 18 are direct current electricity 38, water 39, and hot exhaust gas 40.
  • the temperature of the exhaust gas 40 depends upon the temperature at which the fuel cell operates. For efficiency, preferably the fuel cell 18 is operated at as high a temperature as possible, subject to the material limitations of the fuel cell. For the preferred fuel cell 18, this is in the order of about 1800°F.
  • the fuel cell by itself typically
  • the purpose of the power generation unit 10 is to take advantage of the energy content of the hot exhaust gas 40 from the fuel cell.
  • the efficiency of a commercially available power generation unit by itself, is typically about 30 percent.
  • spent fuel cell exhaust gas 40 is used as a turbine drive gas 48 for driving the turbine 16. Because the generator 14 and compressor 12 are on the same shaft as the turbine, the generator 14 turns, producing alternating current electricity 50, and the compressor 12 compresses the input air stream 32 as described above.
  • the frequency of the electricity 50 produced by the generator is at least 1 ,000 Hz, and typically is from about 1 ,200 to about 1 ,600 Hz.
  • the turbine 16 may not operate at as high a temperature as the fuel cell can operate. Accordingly, it may be necessary to reduce the temperature of the spent fuel cell gas 56.
  • a slip stream 52 of the air compressed by the compressor 12 is combined with the fuel cell exhaust gas 40 upstream of the turbine 16. These two gas streams combined yield the turbine drive gas 48.
  • Spent turbine drive gas 58 is used for heating the compressed air stream 34 in the heating stage 20.
  • a slip stream 56 of the water 39 produced in the fuel cell is introduced into the heating stage 20 with the compressed air stream 34 to attemperate the compressed air.
  • a portion of the water vapor produced in the fuel cell is condensed before it is used to attemperate the compressed air. It is not necessary that the water used in the recuperator come from water produced in the fuel cell. Makeup water 61 from pump 63 can be used instead.
  • Spent turbine drive gas is discharged from the recuperator through line 72.
  • the alternating current electricity 50 from the generator 14 is rectified in the rectifier 22 to direct current electricity 64.
  • This direct current 64 is combined with the direct current 38 from the fuel cell, and inverted in the inverter 24 to produce alternating current power 66.
  • two inverters can be used, one for the direct current 38 from the fuel cell and the other for the direct current 64 from the rectifier 22.
  • the use of separate inverters is less preferred.
  • An advantage of the invention is that because of the relatively low pressure ratio used in the compressor 1 2, generally less than 4: 1 , intercooling between multiple compressor units, as required in some prior designs, is not needed.
  • Example A computer simulation of the system according to the present invention was run. Parameters for the process streams are presented in Table II.
  • the heating value of the fuel was approximately 22,000 Btu/lb
  • ambient temperature was 59 °F
  • ambient pressure was 14.7 psia
  • the compressor had an efficiency of 0.77
  • the rectifier had an efficiency of 0.98
  • the inverter had an efficiency of 0.96
  • the generator had an efficiency of 0.94
  • the turbine efficiency was 0.85
  • the fuel cell had an efficiency of approximately 45 percent.
  • the auxiliary power load of the system was estimated at 3 kW
  • the pressure drop across the fuel cell was 0.5 psi
  • the pressure drop across the piping system was 3 psi.
  • the system operated at a pressure ratio of 3.2.
  • the system generates 1 1 3 kW, with energy efficiency of 57 percent.
  • a system according to the present invention can have an energy efficiency of about 60 percent, soon to be available, at a capital cost of approximately $ 1000 per kilowatt, with minimal transmission cost since they would be located at the user's site, for units sized at about 90 kW capacity.
  • an external cooler such as an air-to-air or air-to-water heat exchanger can be used.
  • a supplementary firing combustor can be added prior to the fuel cell, or a supplementary firing combustor can be added prior to the turbine input, or a supplemental firing combustor can be added in both locations, so that a smaller fuel cell apparatus can be used.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Fuel Cell (AREA)

Abstract

A system for generating electricity comprises a fuel cell (18), a heating stage (20), and an integral power generator (10). The power generator comprises a compressor (12), an electricity generator (14) and a turbine (16). Hot exhaust gas (40) from the fuel cell is used for driving the turbine, which in turn drives the generator and the compressor. Both the fuel cell and the generator produce electricity. The compressor is used for compressing air (32) for use in the fuel cell. A portion of the waste heat from the turbine drive gas (58) is used for preheating the air utilized in the fuel cell.

Description

POWER GENERATION SYSTEM UTILIZING TURBINE GAS GENERATOR AND
FUEL CELL
The present invention is directed to a power generation system.
There is a need for systems for generating electrical energy with high efficiency and minimum environmental pollution. Conventional coal and nuclear plants generally achieve only about 35 percent efficiency. By efficiency, there is meant the amount of electrical energy produced as a percentage of potential energy present in the fossil fuel burned in the power plant. A conventional power installation typically has a capital cost of $600 per kilowatt (1 996 dollars), with distribution charges adding to the capital and operating costs. Recently, General Electric has claimed it has systems that can achieve efficiencies as high as 60 percent, but only in large installations of about 350 megawatts. Medium sized users of electricity, and users in remote locations, would like to have their own small power generation source. However, this is economical only if the capital and operating costs are comparable to those associated with large scale installations, if fuel efficiency is high, and if pollution problems are minimal. However, high efficiencies have not to date been obtainable for smaller size installations. Attempts have been made to improve the efficiency of standard electricity generator systems, and at the same time lower the size required of a highly efficient system, by using fuel cells. For example, Hendricks et al. describe in their U.S. Patent Nos. 5,083,425 and 5,31 9,925 an installation that includes a compressor unit driven by a turbine which receives compressed fluid after passage through an exhaust gas heat exchanger. The installation also includes a power generator driven by a gas turbine, with a fuel cell (typically a solid oxide design) that receives natural gas. The electrical power originating from both the generator and the fuel cell form the output of the installation. Difficulties associated with the Hendricks system are complexity and it has a high capital cost, in that it requires multiple turbines. Accordingly, there is a need for small scale power installation units that have high energy efficiency, have capital and operating costs comparable to those of large scale installations, and create minimum pollution.
SUMMARY The present invention is directed to a system for generating electricity that satisfies these needs. The system comprises as its main components (i) a fuel cell, (ii) a heat exchanger, also referred to as a heating stage or recuperator, and (iii) an integral power generator. The integral power generator comprises three units on a single shaft, namely a compressor, an electricity generator, and a turbine. This system operates on fossil fuel, preferably natural gas, and inexpensively and cleanly generates electricity. In a process using the system, oxygen-containing gas, typically air, is introduced into a gas inlet of the compressor and compressed in the compressor. At least some of the compressed gas is then heated in the heating stage. Fuel and the compressed gas, serving as an oxygen source, are introduced into the fuel cell through an inlet, wherein the fuel is converted by oxidation to produce electricity, water, and hot a exhaust gas. The electricity produced by the fuel cell is one source of electricity generated by this system. Additional electricity is produced by the turbine generator. This electricity is obtained by taking the fuel cell exhaust gas and introducing it into an inlet of the turbine as a drive gas for driving the turbine, which in turn, because they are on the same shaft, drives the generator and the compressor. The turbine operates at at least 50,000 RPM, and generally from about 70,000 to about 90,000 RPM. Thus, for a two-pole generator, the generator produces a high-frequency alternating current, typically at least 800 Hz, and generally from about 1 ,200 to about 1 ,600 Hz. The power from the generator can be converted to direct current, and then combined with the direct current electricity from the fuel cell. This combined direct current can then be inverted in an inverter to produce relatively low-frequency alternating current for consumption, typically having a frequency of 50 to 60 Hz.
Spent turbine drive gas, once discharged from the turbine through an outlet, is used for heating the oxygen-containing gas fed to the fuel ceil in the heating stage by introducing spent turbine drive gas into an inlet of the heating stage. Thus, due to the direct linking of the fuel cell with the power generator, inexpensive electricity is generated.
The exhaust gas from the fuel cell may be at a higher temperature, i.e, about 1 800°F, than commercially available turbine power generators can operate, which is generally in the order of only about 1 600-1700 °F. Therefore, preferably, the turbine drive gas includes a sufficient quantity of compressed gas from the compressor to maintain the turbine drive gas at a sufficiently low temperature that it does not damage the turbine.
It is also preferred that water be combined with the compressed air before it is introduced into the heat exchanger to maximize the heat recovery from the turbine exhaust gas. The water used for this purpose can be water generated in the fuel ceil or from an independent source.
DRAWINGS
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description, appended claims, and accompanying drawing, which is a process flow sheet of a system according to the present invention, wherein the principal components of the system are schematically shown.
DESCRIPTION
With reference to the drawing figure, the main components of a system according to the present invention are:
(a) a power generator 10 comprising a compressor 12, an electrical generator 14, and a turbine 16, all sharing a common shaft 17;
(b) a fuel cell 18;
(c) a recuperator or regenerator 20, also referred to as a heating stage or heat exchanger;
(d) a rectifier 22; and (e) an inverter 24.
The power generation unit shown in the drawing has the compressor 12, the generator 14, and the turbine 16 mounted on the same shaft 17 in that sequential order, but that is not required. For example, the turbine 16 can be between the generator 14 and the compressor 12, or the compressor 12 can be between the generator 14 and the turbine 16.
A suitable power generator can be obtained from Capstone Turbine Corporation of Tarzana, California. The Capstone power generator referred to has a turbine 16 which generates about 24 kW. Another satisfactory power generation will be available from Allied Signal of Torrance, California, which has a turbine providing from about 40 to about 50 kW, and larger units are planned up to 200 kW.
The compressor 12 and the turbine 16, which turn on a common shaft with the generator 14 at high speed, can each or both be radial (centrifugal) design, or both can be an axial flow design. Other options are that the bearings required for the power generation unit 10 can be located on the shaft 17 with the generator 14 cantilevered on the shaft, or the generator 14 can be located between the bearings. Air bearings are preferred to reduce the complexity of the machine. The high speed generator 14 uses a permanent magnet to supply the necessary magnetic lines of force.
The fuel cell 18 catalytically converts methane to hydrogen and carbon dioxide with heat generation; and the hydrogen is then combined with oxygen in an oxygen-containing gas to generate electricity, plus waste heat and water.
Different types of fuel cells are suitable for use in the system of the invention. One type that can be used is a molten carbonate fuel cell. Also, a phosphoric acid fuel cell can be used. A low-temperature fuel cell, such as a proton exchange membrane or phosphoric acid can be used, but with less efficiency. The preferred fuel cell is a solid oxide fuel cell, which typically operates at a temperature from 1 600 to 1 800°F.
A solid oxide fuel cell can be obtained from Westinghouse, Pittsburgh, Pennsylvania. The Westinghouse fuel cells can be obtained in any size, in 250 watt increments.
The heating stage 20 can be a fixed recuperator or a revolving regenerator. The rectifier 22 is typically a diode system whose purpose is to convert high-frequency alternating current to direct current.
The purpose of the inverter 24 is to convert direct current to a low- frequency, alternating current, typically 50 to 60 Hz, for domestic use.
There will now be described how the system is used, with reference to Table I. Table I provides the temperature, pressure, and flow rates of the various streams of the system shown in the drawing.
TABLE I Typical Process Parameters
Figure imgf000006_0001
The inputs to the system are an oxygen-containing gas, typically air 32, and a fuel 34, which is typically natural gas, which is principally made up of methane. The input air 32 is used for oxidizing the fuel 34 in the fuel cell, after it is compressed and heated. The air 32 is first compressed in the compressor 12. The compressed oxygen- containing gas 34 is then heated in the heating stage 26, to produce the heated, compressed, input oxygen-containing gas stream 37 for the fuel cell 18. Although the oxygen-containing gas is typically air 32, it can be other gases containing oxygen, such as air partially depleted of oxygen, or air enriched with oxygen. The outputs from the fuel cell 18 are direct current electricity 38, water 39, and hot exhaust gas 40. The temperature of the exhaust gas 40 depends upon the temperature at which the fuel cell operates. For efficiency, preferably the fuel cell 18 is operated at as high a temperature as possible, subject to the material limitations of the fuel cell. For the preferred fuel cell 18, this is in the order of about 1800°F. The fuel cell by itself typically has an energy efficiency of about 45 percent.
The purpose of the power generation unit 10 is to take advantage of the energy content of the hot exhaust gas 40 from the fuel cell. The efficiency of a commercially available power generation unit by itself, is typically about 30 percent. By combining the power generation unit 10 with the fuel cell 18, a system with an energy efficiency of about 60 percent results.
Accordingly, spent fuel cell exhaust gas 40 is used as a turbine drive gas 48 for driving the turbine 16. Because the generator 14 and compressor 12 are on the same shaft as the turbine, the generator 14 turns, producing alternating current electricity 50, and the compressor 12 compresses the input air stream 32 as described above. The frequency of the electricity 50 produced by the generator is at least 1 ,000 Hz, and typically is from about 1 ,200 to about 1 ,600 Hz.
The turbine 16 may not operate at as high a temperature as the fuel cell can operate. Accordingly, it may be necessary to reduce the temperature of the spent fuel cell gas 56. Preferably, a slip stream 52 of the air compressed by the compressor 12 is combined with the fuel cell exhaust gas 40 upstream of the turbine 16. These two gas streams combined yield the turbine drive gas 48.
Spent turbine drive gas 58 is used for heating the compressed air stream 34 in the heating stage 20. To maximize the recovery of the heat from the spent turbine drive gas 58, preferably a slip stream 56 of the water 39 produced in the fuel cell is introduced into the heating stage 20 with the compressed air stream 34 to attemperate the compressed air. A portion of the water vapor produced in the fuel cell is condensed before it is used to attemperate the compressed air. It is not necessary that the water used in the recuperator come from water produced in the fuel cell. Makeup water 61 from pump 63 can be used instead. Spent turbine drive gas is discharged from the recuperator through line 72.
The alternating current electricity 50 from the generator 14 is rectified in the rectifier 22 to direct current electricity 64. This direct current 64 is combined with the direct current 38 from the fuel cell, and inverted in the inverter 24 to produce alternating current power 66.
Rather than using a single inverter 24, two inverters can be used, one for the direct current 38 from the fuel cell and the other for the direct current 64 from the rectifier 22. The use of separate inverters is less preferred.
An advantage of the invention is that because of the relatively low pressure ratio used in the compressor 1 2, generally less than 4: 1 , intercooling between multiple compressor units, as required in some prior designs, is not needed.
Example A computer simulation of the system according to the present invention was run. Parameters for the process streams are presented in Table II.
TABLE II Process Parameters for Example
Figure imgf000008_0001
It was assumed that the heating value of the fuel was approximately 22,000 Btu/lb, ambient temperature was 59 °F, ambient pressure was 14.7 psia, that the compressor had an efficiency of 0.77, the rectifier had an efficiency of 0.98, the inverter had an efficiency of 0.96, the generator had an efficiency of 0.94, the turbine efficiency was 0.85, and the fuel cell had an efficiency of approximately 45 percent. The auxiliary power load of the system was estimated at 3 kW, the pressure drop across the fuel cell was 0.5 psi, and the pressure drop across the piping system was 3 psi. The system operated at a pressure ratio of 3.2.
At these parameters, the system generates 1 1 3 kW, with energy efficiency of 57 percent.
Accordingly, a system according to the present invention can have an energy efficiency of about 60 percent, soon to be available, at a capital cost of approximately $ 1000 per kilowatt, with minimal transmission cost since they would be located at the user's site, for units sized at about 90 kW capacity. Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. For example, rather than using a slip stream of compressed air for reducing the turbine inlet temperature, an external cooler, such as an air-to-air or air-to-water heat exchanger can be used. As another option, a supplementary firing combustor can be added prior to the fuel cell, or a supplementary firing combustor can be added prior to the turbine input, or a supplemental firing combustor can be added in both locations, so that a smaller fuel cell apparatus can be used.
Therefore, the scope of the appended claims should not be limited to the description of the preferred versions contained herein.

Claims

1 . A process for generating electricity utilizing an integral, power generator comprising a compression stage, an electricity generation stage, and a turbine stage all on the same shaft, the process comprising the steps of:
(a) compressing an oxygen-containing gas in the compression stage;
(b) heating at least some of the compressed gas in a heating stage;
(c) introducing fuel and the compressed heated gas into a fuel cell for oxidizing the fuel therein to produce electricity, the fuel cell also producing hot exhaust gas;
(d) driving the turbine stage with a turbine drive gas comprising fuel cell exhaust gas, the turbine stage being driven at a speed of a least 50,000 rpm, the turbine stage driving the electricity generation stage and the compression stage, the generation stage generating alternating current electricity; and (e) withdrawing spent fuel cell exhaust gas from the turbine stage and introducing the spent gas into the heating stage for heating the compressed oxygen- containing gas.
2. The process of claim 1 comprising the additional step of introducing water into the heating stage with compressed gas to increase the amount of heat recovered from the spent gas.
3. The process of claim 2 wherein the fuel cell produces water, and wherein the step of introducing water into the heating stage comprises introducing water produced by the fuel cell.
4. The process of claim 1 wherein the turbine drive gas comprises sufficient compressed oxygen-containing gas that the turbine drive gas has a temperature sufficiently low that the turbine stage is not damaged by the turbine drive gas.
5. The process of claim 4 wherein the fuel cell operates at a higher temperature than does the turbine stage.
6. The process of claim 1 wherein the fuel cell operates at a higher temperature than does the turbine stage.
7. The process of claim 1 comprising the step of rectifying the alternating current to direct current, and inverting both direct currents to low frequency alternating current.
8. The process of claim 1 wherein the low frequency alternating current electricity is at about 50 to about 60 Hz.
9. A process for generating electricity utilizing an integral, power generator comprising a compression stage, an electricity generation stage, and a turbine stage all on the same shaft, the process comprising the steps of:
(a) compressing an oxygen-containing gas in the compression stage;
(b) introducing compressed oxygen-containing gas and water into a heating stage to produce a hot, compressed, oxygen-containing gas;
(c) introducing a methane-containing fuel and the hot, compressed, oxygen- containing gas into a fuel cell for oxidizing the fuel therein to produce direct current electricity, the fuel cell also producing hot fuel cell exhaust gas;
(d) combining the fuel cell exhaust gas with sufficient compressed oxygen- containing gas to produce a turbine drive gas having a temperature sufficiently low that the turbine stage is not damaged by the turbine drive gas, and driving the turbine stage with turbine drive gas at a speed of a least 50,000 rpm so that the turbine stage drives the electricity generation stage and the compression stage, the generation stage generating high frequency alternating current electricity;
(e) withdrawing spent fuel cell exhaust gas from the turbine stage and introducing the spent gas into the heating stage for heating the compressed oxygen- containing gas; and
(f) rectifying the alternating current electricity to generator-produced direct current electricity, and inverting both the fuel cell-produced direct current electricity and the generator-produced direct current electricity to low-frequency alternating current.
10. A system for generating electricity comprising:
(a) an integral, power generator comprising a compressor, an electricity generator, and a turbine, all on the same shaft, the compressor having a gas inlet for introducing an oxygen-containing gas into the compressor to generate a compressed oxygen-containing gas; (b) a heating stage for heating at least some of the compressed oxygen- containing gas;
(c) a fuel cell for converting a fuel, in the presence of an oxygen source, into direct current electrical energy, the fuel cell having a gas inlet for receiving heated compressed oxygen-containing gas from the heating stage for use in the fuel cell as the oxygen source, the fuel cell also producing a hot exhaust gas;
(d) wherein the turbine stage has an inlet for turbine drive gas comprising fuel cell exhaust gas so that the turbine drives the generator and the compressor, the generator generating alternating current electricity, and wherein the turbine stage has an outlet for hot spent drive gas; and
(e) wherein the heating stage has an inlet for the hot spent drive gas for heating the compressed oxygen-containing gas.
1 1 . The system of claim 10 comprising a rectifier for rectifying the alternating current electricity to generator-produced direct current electricity.
1 2. The system of claim 1 1 comprising an invertor for inverting both the fuel cell-produced direct current electricity and the generator-produced direct current electricity to low-frequency alternating current.
1 3. The system of claim 10 comprising a mixer for mixing the fuel cell exhaust gas with sufficient compressed oxygen-containing gas to produce a turbine drive gas having a temperature sufficiently low that the turbine stage is not damaged by the turbine drive gas.
PCT/US1998/000250 1998-01-08 1998-01-08 Power generation system utilizing turbine gas generator and fuel cell WO1999035702A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU58168/98A AU5816898A (en) 1998-01-08 1998-01-08 Power generation system utilizing turbine gas generator and fuel cell
PCT/US1998/000250 WO1999035702A1 (en) 1998-01-08 1998-01-08 Power generation system utilizing turbine gas generator and fuel cell

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US1998/000250 WO1999035702A1 (en) 1998-01-08 1998-01-08 Power generation system utilizing turbine gas generator and fuel cell

Publications (1)

Publication Number Publication Date
WO1999035702A1 true WO1999035702A1 (en) 1999-07-15

Family

ID=22266161

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1998/000250 WO1999035702A1 (en) 1998-01-08 1998-01-08 Power generation system utilizing turbine gas generator and fuel cell

Country Status (2)

Country Link
AU (1) AU5816898A (en)
WO (1) WO1999035702A1 (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10249588A1 (en) * 2002-04-16 2004-05-13 Airbus Deutschland Gmbh Water-generating method for generating water on board aircraft via fuel cells integrates a water-generating unit in an aircraft's driving gear as high-temperature fuel cells
DE10216709B4 (en) * 2001-10-11 2006-11-16 Airbus Deutschland Gmbh Process for the treatment and distribution of airborne water in air, land and / or water vehicles
DE10216710B4 (en) * 2001-10-11 2006-11-16 Airbus Deutschland Gmbh Arrangement for generating water on board an aircraft
US7550218B2 (en) 2001-10-11 2009-06-23 Airbus Deutschland Gmbh Apparatus for producing water onboard of a craft driven by a power plant
US7767359B2 (en) 2002-10-24 2010-08-03 Airbus Deutschland Gmbh Device for producing water on board of an airplane
EP3142177A1 (en) * 2015-09-13 2017-03-15 Honeywell International Inc. Fuel cell regulation using loss recovery systems
CN110534771A (en) * 2018-05-24 2019-12-03 曼恩能源方案有限公司 The device of the air supply of fuel cell for the preferred handling hydrogen of fuel cell

Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1436747A (en) * 1965-03-17 1966-04-29 Gaz De France Installations for generating electricity and thermal energy comprising fuel cell batteries operating at high temperature and method of using these installations
JPS60195880A (en) * 1984-03-19 1985-10-04 Hitachi Ltd Power generation system using solid electrolyte fuel cell
JPS63119163A (en) * 1986-11-07 1988-05-23 Mitsubishi Heavy Ind Ltd Fuel cell generating system
JPS63166157A (en) * 1986-12-26 1988-07-09 Mitsubishi Heavy Ind Ltd Solid electrolyte fuel cell power generating system
JPS63216270A (en) * 1987-03-03 1988-09-08 Mitsubishi Heavy Ind Ltd Power generating system for solid electrolyte fuel cell
JPH01126137A (en) * 1987-11-10 1989-05-18 Osaka Gas Co Ltd Power equipment using fuel cell
US5083425A (en) 1989-05-29 1992-01-28 Turboconsult Power installation using fuel cells
WO1992007392A1 (en) * 1990-10-15 1992-04-30 Mannesmann Ag Process and installation for the combined generation of electrical and mechanical energy
US5413879A (en) * 1994-02-08 1995-05-09 Westinghouse Electric Corporation Integrated gas turbine solid oxide fuel cell system
US5449568A (en) * 1993-10-28 1995-09-12 The United States Of America As Represented By The United States Department Of Energy Indirect-fired gas turbine bottomed with fuel cell
JPH0845523A (en) * 1994-08-03 1996-02-16 Mitsubishi Heavy Ind Ltd Fuel cell/gas turbine combined generation system
WO1996005625A2 (en) * 1994-08-08 1996-02-22 Ztek Corporation Ultra-high efficiency turbine and fuel cell combination
US5541014A (en) * 1995-10-23 1996-07-30 The United States Of America As Represented By The United States Department Of Energy Indirect-fired gas turbine dual fuel cell power cycle
WO1997028573A1 (en) * 1996-01-31 1997-08-07 Westinghouse Electric Corporation Purge gas protected transportable pressurized fuel cell modules and their operation in a power plant

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1436747A (en) * 1965-03-17 1966-04-29 Gaz De France Installations for generating electricity and thermal energy comprising fuel cell batteries operating at high temperature and method of using these installations
JPS60195880A (en) * 1984-03-19 1985-10-04 Hitachi Ltd Power generation system using solid electrolyte fuel cell
JPS63119163A (en) * 1986-11-07 1988-05-23 Mitsubishi Heavy Ind Ltd Fuel cell generating system
JPS63166157A (en) * 1986-12-26 1988-07-09 Mitsubishi Heavy Ind Ltd Solid electrolyte fuel cell power generating system
JPS63216270A (en) * 1987-03-03 1988-09-08 Mitsubishi Heavy Ind Ltd Power generating system for solid electrolyte fuel cell
JPH01126137A (en) * 1987-11-10 1989-05-18 Osaka Gas Co Ltd Power equipment using fuel cell
US5319925A (en) 1989-05-28 1994-06-14 A.S.A. B.V. Installation for generating electrical energy
US5083425A (en) 1989-05-29 1992-01-28 Turboconsult Power installation using fuel cells
WO1992007392A1 (en) * 1990-10-15 1992-04-30 Mannesmann Ag Process and installation for the combined generation of electrical and mechanical energy
US5449568A (en) * 1993-10-28 1995-09-12 The United States Of America As Represented By The United States Department Of Energy Indirect-fired gas turbine bottomed with fuel cell
US5413879A (en) * 1994-02-08 1995-05-09 Westinghouse Electric Corporation Integrated gas turbine solid oxide fuel cell system
JPH0845523A (en) * 1994-08-03 1996-02-16 Mitsubishi Heavy Ind Ltd Fuel cell/gas turbine combined generation system
WO1996005625A2 (en) * 1994-08-08 1996-02-22 Ztek Corporation Ultra-high efficiency turbine and fuel cell combination
US5541014A (en) * 1995-10-23 1996-07-30 The United States Of America As Represented By The United States Department Of Energy Indirect-fired gas turbine dual fuel cell power cycle
WO1997028573A1 (en) * 1996-01-31 1997-08-07 Westinghouse Electric Corporation Purge gas protected transportable pressurized fuel cell modules and their operation in a power plant

Non-Patent Citations (8)

* Cited by examiner, † Cited by third party
Title
HSU M ET AL: "ZTEK'S ULTRA-HIGH EFFICIENCY FUEL CELL/GAS TURBINE SYSTEM FOR DISTRIBUTED GENERATION", PROCEEDINGS OF THE AMERICAN POWER CONFERENCE, vol. 59-01, 1997, pages 559 - 561, XP000198317 *
KRUMPELT M ET AL: "SYSTEMS ANALYSIS FOR HIGH-TEMPERATURE FUEL CELLS", EXTENDED ABSTRACTS, vol. 87-02, 18 October 1987 (1987-10-18), pages 261/262, XP000115057 *
PATENT ABSTRACTS OF JAPAN vol. 010, no. 039 (E - 381) 15 February 1986 (1986-02-15) *
PATENT ABSTRACTS OF JAPAN vol. 012, no. 367 (E - 664) 30 September 1988 (1988-09-30) *
PATENT ABSTRACTS OF JAPAN vol. 012, no. 430 (E - 682) 14 November 1988 (1988-11-14) *
PATENT ABSTRACTS OF JAPAN vol. 013, no. 005 (E - 701) 9 January 1989 (1989-01-09) *
PATENT ABSTRACTS OF JAPAN vol. 013, no. 374 (E - 808) 18 August 1989 (1989-08-18) *
PATENT ABSTRACTS OF JAPAN vol. 096, no. 006 28 June 1996 (1996-06-28) *

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10216709B4 (en) * 2001-10-11 2006-11-16 Airbus Deutschland Gmbh Process for the treatment and distribution of airborne water in air, land and / or water vehicles
DE10216710B4 (en) * 2001-10-11 2006-11-16 Airbus Deutschland Gmbh Arrangement for generating water on board an aircraft
US7550218B2 (en) 2001-10-11 2009-06-23 Airbus Deutschland Gmbh Apparatus for producing water onboard of a craft driven by a power plant
DE10249588A1 (en) * 2002-04-16 2004-05-13 Airbus Deutschland Gmbh Water-generating method for generating water on board aircraft via fuel cells integrates a water-generating unit in an aircraft's driving gear as high-temperature fuel cells
DE10249588B4 (en) * 2002-04-16 2006-10-19 Airbus Deutschland Gmbh Arrangement for generating water on board an aircraft
US7767359B2 (en) 2002-10-24 2010-08-03 Airbus Deutschland Gmbh Device for producing water on board of an airplane
EP3142177A1 (en) * 2015-09-13 2017-03-15 Honeywell International Inc. Fuel cell regulation using loss recovery systems
CN106532086A (en) * 2015-09-13 2017-03-22 霍尼韦尔国际公司 Fuel cell regulation using loss recovery systems
US10033056B2 (en) 2015-09-13 2018-07-24 Honeywell International Inc. Fuel cell regulation using loss recovery systems
EP3758119A1 (en) * 2015-09-13 2020-12-30 Garrett Transportation I Inc. Fuel cell regulation using loss recovery systems
CN106532086B (en) * 2015-09-13 2021-05-04 盖瑞特交通一公司 Vehicle electrical system and method of operating turbine assembly
CN110534771A (en) * 2018-05-24 2019-12-03 曼恩能源方案有限公司 The device of the air supply of fuel cell for the preferred handling hydrogen of fuel cell

Also Published As

Publication number Publication date
AU5816898A (en) 1999-07-26

Similar Documents

Publication Publication Date Title
US5811201A (en) Power generation system utilizing turbine and fuel cell
US4041210A (en) Pressurized high temperature fuel cell power plant with bottoming cycle
US5417051A (en) Process and installation for the combined generation of electrical and mechanical energy
CA1043860A (en) Pressurized fuel cell power plant with air bypass
CA1043861A (en) Pressurized fuel cell power plant
US6897577B2 (en) Methods and system for power generation
US20060053792A1 (en) Power generation system and method of operating same
EP1659654A1 (en) Recuperated atmospheric SOFC/Gas turbine hybrid cycle
JPH0789494B2 (en) Combined power plant
WO2001095409A3 (en) Joint-cycle high-efficiency fuel cell system with power generating turbine
EP2127005A1 (en) Integrated fuel cell and heat engine hybrid system for high efficiency power generation
KR20090064853A (en) The power plant system combined with self-starting gas turbine using the fuel cell
US6608395B1 (en) Hybrid combined cycle power generation facility
JPH11297336A (en) Composite power generating system
Luo et al. Energy and exergy analysis of power generation systems with chemical looping combustion of coal
CA1157910A (en) Method of generating electricity using an endothermic coal gasifier and mhd generator
WO1999035702A1 (en) Power generation system utilizing turbine gas generator and fuel cell
JP3804204B2 (en) Fuel cell power generator with multi-stage turbine compressor
Steinfeld et al. High efficiency carbonate fuel cell/turbine hybrid power cycle
CN211789285U (en) Purge gas utilization system based on fuel cell combined power generation
CN207728443U (en) One kind three recycles type coal gasification melting carbonate fuel cell generation system
EP4187061A1 (en) Method and apparatus for co-generating electricity in a process plant integrated with a thermal power generator
CA2353073C (en) Combined multi-fuel electrical generator and method
Ghezel-Ayagh et al. Development of hybrid power systems based on direct fuel cell/turbine cycle
JPS6257073B2 (en)

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE GH GM GW HU ID IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT UA UG US UZ VN YU ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: CA