17-11-2012, 04:03 PM
Fuel Cell/Gas Turbine Hybrid Systems
[attachment=40022]
Abstract
The National Fuel Cell Research Center (NFCRC) was established to accelerate the evolution
of fuel cells and fuel cell systems. In addition to addressing the key research challenges in
the emergence of fuel cells, the Center assists the market to understand this unusual power
system and the opportunities for both central and distributed generation. An intriguing fuel
cell research initiative in which the NFCRC is focused addresses the development of hybrid
turbocell systems. With an unusually high fuel-to-electrical efficiency, hybrid systems
portend a major paradigm shift for the future generation of power in a variety of applications.
The first demonstrations of both high-pressure and atmospheric pressure hybrid systems
verify the basic principles of the technology, delineate the component features that require
technology advances, and confirm the viability of the product for a near-term and long-term
market for a broad variety of applications in both stationary and transportation. Both the
Molten Carbonate Fuel Cell (MCFC) and the Solid Oxide Fuel Cell (SOFC) are attractive for
hybridization due to the high operating and effluent temperature. Systems are emerging for
distributed generation (15kW to 50 MW) with combinations of high-temperature fuel cells
(HTFCs) and micro-turbine generators (MTGs). Concepts are also evolving for central plant
configurations (~300MW) where ultra high-efficiency on both natural gas and coal are
desired in combination with zero-emission of criteria pollutants, CO2 sequestration, and
hydrogen co-production.
Introduction
The application of fuel cell technologies to advanced power generation systems signifies the
most significant advancement in energy conservation and environmental protection for the
next decade. The National Fuel Cell Research Center (NFCRC) was established in 1998 to
provide key leadership in the development and application of these new technologies. The
mission is to promote and support the genesis of fuel cell power generation systems by
providing technological leadership with a vigorous program of research and beta testing,
coupled with education and technology transfer to and from the marketplace.
For several reasons, the NFCRC offers a timely focus on an emerging new power technology.
First, fuel cells represent the most important new power generation technology of this decade.
Second, the technologys successful emergence is constrained in the absence of an
institutional magnet that can attract and coalesce the various stakeholders into an integrated
effort to pursue technical development and raise awareness of fuel cells. One example of a
major new fuel cell technology is the Hybrid System where a fuel cell is combined with
another power generation device to create a synergy with attributes that exceed the sum of the
two when combined.
Hybrid Systems
The NFCRC is engaged in a variety of fuel cell initiatives. One of the more intriguing is the
development of Hybrid Systems. The NFCRC is developing steady-state and dynamic
models, applying these models to a wide spectrum of Hybrid concepts, and is currently
hosting the demonstration of the first Hybrid system to be fabricated and operated.
Hybrid Systems are power generation systems in which a heat engine, such as a gas
turbine, is combined with a non-heat-engine, such as a fuel cell. The resulting system
exhibits a synergism in which the combination performs with an efficiency that far exceeds
that which can be provided by either system alone. Thus the combination performs better
than the sum of its parts.
Technical Features
A fuel cell generates electricity directly through electrochemical reactions and is more
efficient than a heat engine because it eliminates the mechanical or rotating machinery
(Figure 1). Because the performance of a fuel cell is not restricted by the Carnot Law
constraints that limit heat engine efficiencies, the fuel cell will likely be the core of a highefficiency
hybrid power cycle
MTG-SOFC: Distributed Power Generation
The first Hybrid demonstration of a pressurized MTG-SOFC (Figure 1) is being conducted at
the NFCRC (Figure 4). This initiative, lead by Southern California Edison, is a 220 kW unit
that utilizes a Siemens Westinghouse SOFC and an Ingersoll-Rand Energy Systems
microturbine generator (MTG). The system to date has achieved over 2,000 hours of
operation and attained the world record in fuel-to-electricity conversion efficiency. The unit
is natural gas fired and the load is controlled through two (an AC for the turbine output, and a
DC for the fuel cell output) dissipaters.
MTG-SOFC: Central Power Generation
Under the sponsorship of the DOE, a multi-disciplinary team led by the Advanced Power and
Energy Program(APEP) of the University of California at Irvine is defining the system
engineering issues associated with the integration of key components and subsystems into
central power plant systems that meet stretch performance and emission goals for both
natural gas and coal fuel fired operation. The myriad of fuel processing, power generation,
and emission control technologies are narrowed down to selected scenarios in order to
identify those combinations that have the potential to achieve the program goals of high
efficiency and minimized environmental impact while using fossil fuels. The technology
levels considered are based on projected technical and manufacturing advances being made in
industry and on advances identified in current and future government supported research.
Examples of systems included in these advanced cycles are high-temperature fuel cells,
advanced gas turbines, ion transport membrane separation and hydrogen-oxygen combustion.
[attachment=40022]
Abstract
The National Fuel Cell Research Center (NFCRC) was established to accelerate the evolution
of fuel cells and fuel cell systems. In addition to addressing the key research challenges in
the emergence of fuel cells, the Center assists the market to understand this unusual power
system and the opportunities for both central and distributed generation. An intriguing fuel
cell research initiative in which the NFCRC is focused addresses the development of hybrid
turbocell systems. With an unusually high fuel-to-electrical efficiency, hybrid systems
portend a major paradigm shift for the future generation of power in a variety of applications.
The first demonstrations of both high-pressure and atmospheric pressure hybrid systems
verify the basic principles of the technology, delineate the component features that require
technology advances, and confirm the viability of the product for a near-term and long-term
market for a broad variety of applications in both stationary and transportation. Both the
Molten Carbonate Fuel Cell (MCFC) and the Solid Oxide Fuel Cell (SOFC) are attractive for
hybridization due to the high operating and effluent temperature. Systems are emerging for
distributed generation (15kW to 50 MW) with combinations of high-temperature fuel cells
(HTFCs) and micro-turbine generators (MTGs). Concepts are also evolving for central plant
configurations (~300MW) where ultra high-efficiency on both natural gas and coal are
desired in combination with zero-emission of criteria pollutants, CO2 sequestration, and
hydrogen co-production.
Introduction
The application of fuel cell technologies to advanced power generation systems signifies the
most significant advancement in energy conservation and environmental protection for the
next decade. The National Fuel Cell Research Center (NFCRC) was established in 1998 to
provide key leadership in the development and application of these new technologies. The
mission is to promote and support the genesis of fuel cell power generation systems by
providing technological leadership with a vigorous program of research and beta testing,
coupled with education and technology transfer to and from the marketplace.
For several reasons, the NFCRC offers a timely focus on an emerging new power technology.
First, fuel cells represent the most important new power generation technology of this decade.
Second, the technologys successful emergence is constrained in the absence of an
institutional magnet that can attract and coalesce the various stakeholders into an integrated
effort to pursue technical development and raise awareness of fuel cells. One example of a
major new fuel cell technology is the Hybrid System where a fuel cell is combined with
another power generation device to create a synergy with attributes that exceed the sum of the
two when combined.
Hybrid Systems
The NFCRC is engaged in a variety of fuel cell initiatives. One of the more intriguing is the
development of Hybrid Systems. The NFCRC is developing steady-state and dynamic
models, applying these models to a wide spectrum of Hybrid concepts, and is currently
hosting the demonstration of the first Hybrid system to be fabricated and operated.
Hybrid Systems are power generation systems in which a heat engine, such as a gas
turbine, is combined with a non-heat-engine, such as a fuel cell. The resulting system
exhibits a synergism in which the combination performs with an efficiency that far exceeds
that which can be provided by either system alone. Thus the combination performs better
than the sum of its parts.
Technical Features
A fuel cell generates electricity directly through electrochemical reactions and is more
efficient than a heat engine because it eliminates the mechanical or rotating machinery
(Figure 1). Because the performance of a fuel cell is not restricted by the Carnot Law
constraints that limit heat engine efficiencies, the fuel cell will likely be the core of a highefficiency
hybrid power cycle
MTG-SOFC: Distributed Power Generation
The first Hybrid demonstration of a pressurized MTG-SOFC (Figure 1) is being conducted at
the NFCRC (Figure 4). This initiative, lead by Southern California Edison, is a 220 kW unit
that utilizes a Siemens Westinghouse SOFC and an Ingersoll-Rand Energy Systems
microturbine generator (MTG). The system to date has achieved over 2,000 hours of
operation and attained the world record in fuel-to-electricity conversion efficiency. The unit
is natural gas fired and the load is controlled through two (an AC for the turbine output, and a
DC for the fuel cell output) dissipaters.
MTG-SOFC: Central Power Generation
Under the sponsorship of the DOE, a multi-disciplinary team led by the Advanced Power and
Energy Program(APEP) of the University of California at Irvine is defining the system
engineering issues associated with the integration of key components and subsystems into
central power plant systems that meet stretch performance and emission goals for both
natural gas and coal fuel fired operation. The myriad of fuel processing, power generation,
and emission control technologies are narrowed down to selected scenarios in order to
identify those combinations that have the potential to achieve the program goals of high
efficiency and minimized environmental impact while using fossil fuels. The technology
levels considered are based on projected technical and manufacturing advances being made in
industry and on advances identified in current and future government supported research.
Examples of systems included in these advanced cycles are high-temperature fuel cells,
advanced gas turbines, ion transport membrane separation and hydrogen-oxygen combustion.