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Title: High efficiency fuel cell/advanced turbine power cycles

Abstract

An outline of the Westinghouse high-efficiency fuel cell/advanced turbine power cycle is presented. The following topics are discussed: The Westinghouse SOFC pilot manufacturing facility, cell scale-up plan, pressure effects on SOFC power and efficiency, sureCell versus conventional gas turbine plants, sureCell product line for distributed power applications, 20 MW pressurized-SOFC/gas turbine power plant, 10 MW SOFC/CT power plant, sureCell plant concept design requirements, and Westinghouse SOFC market entry.

Authors:
 [1]
  1. Westinghouse Electric Corp., Orlando, FL (United States)
Publication Date:
Research Org.:
USDOE Morgantown Energy Technology Center, WV (United States)
OSTI Identifier:
426100
Report Number(s):
DOE/METC-96/1024; CONF-9510272-
ON: DE96000644; TRN: 96:006563-0002
Resource Type:
Conference
Resource Relation:
Conference: Workshop on very high efficiency fuel cell/advanced turbine power cycles, Morgantown, WV (United States), 19 Oct 1995; Other Information: PBD: 19 Oct 1995; Related Information: Is Part Of Proceedings of the workshop on very high efficiency fuel cell/gas turbine power cycles; Williams, M.C.; Zeh, C.M.; PB: 92 p.
Country of Publication:
United States
Language:
English
Subject:
20 FOSSIL-FUELED POWER PLANTS; 30 DIRECT ENERGY CONVERSION; FUEL CELL POWER PLANTS; EFFICIENCY; DESIGN; GAS TURBINE POWER PLANTS; MANUFACTURING; NITROGEN OXIDES

Citation Formats

Morehead, H. High efficiency fuel cell/advanced turbine power cycles. United States: N. p., 1995. Web.
Morehead, H. High efficiency fuel cell/advanced turbine power cycles. United States.
Morehead, H. 1995. "High efficiency fuel cell/advanced turbine power cycles". United States. doi:. https://www.osti.gov/servlets/purl/426100.
@article{osti_426100,
title = {High efficiency fuel cell/advanced turbine power cycles},
author = {Morehead, H.},
abstractNote = {An outline of the Westinghouse high-efficiency fuel cell/advanced turbine power cycle is presented. The following topics are discussed: The Westinghouse SOFC pilot manufacturing facility, cell scale-up plan, pressure effects on SOFC power and efficiency, sureCell versus conventional gas turbine plants, sureCell product line for distributed power applications, 20 MW pressurized-SOFC/gas turbine power plant, 10 MW SOFC/CT power plant, sureCell plant concept design requirements, and Westinghouse SOFC market entry.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1995,
month =
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

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  • The following figures are included: Westinghouse (W.) SOFC pilot manufacturing facility; cell scale-up plan; W. 25 kW SOFC unit at the utility`s facility on Rokko Island; pressure effect on SOFC power and efficiency; SureCELL{trademark} vs conventional gas turbine plants; SureCELL{trademark} product line for distributed power applications; 20 MW pressurized SOFC/gas turbine power plant; 10 MW SOFT/CT power plant; SureCELL{trademark} plant concept design requirements; and W. SOFC market entry.
  • The U.S. Department of Energy`s (DOE`s) Morgantown Energy Technology Center (METC) held a workshop on October 19, 1995, to explore the subject of Very High Efficiency Fuel Cell/Gas Turbine Power Plants. The combination of these two technologies has the potential for enormous synergies in that it offers a solution to two important problems: the low efficiency and relatively high nitrogen oxides (NO{sub x}) emissions of small gas turbines, and the high cost of small fuel-cell power plants. Small gas turbines, with capacities of less than 10 megawatts (MW), typically have efficiencies in the 25 to 30 percent range. Small fuelmore » cells are predicted to cost $1,000 to 1,500 per kilowatt (kW) when commercially available in the years after 2000. If the early efforts are successful in commercializing these products, the foundation will be laid for scaling up the technology to large-scale power plants. This is important since the combination, at the scale of 200 MW or more, can achieve efficiencies of 75 percent or more. This is significantly higher than other technologies for generating electricity from natural gas. As a result, carbon dioxide (CO{sub 2}) emissions could also be significantly reduced. In comparison, the best currently available, large scale, combined-cycle power plants have an efficiency of about 58 percent. That level will likely increase to 60 to 62 percent over the next decade, as a result of the Advanced Turbine System (ATS) program sponsored by DOE. The highest efficiencies currently projected for several fuel cell technologies, which are now under development, are in the range of 55 to 65 percent for stand-alone, fuel-cell power plants. The presentations focused on the cycle analysis studies that have been done as well as suggestions from gas turbine and fuel cell vendors on how to arrange these components in practical and reliable configurations. Individual projects have been processed separately for the United States Department of Energy databases.« less
  • Carbonate fuel cells developed by Energy Research Corporation, in commercial 2.85 MW size, have an efficiency of 57.9 percent. Studies of higher efficiency hybrid power cycles were conducted in cooperation with METC to identify an economically competitive system with an efficiency in excess of 65 percent. A hybrid power cycle was identified that includes a direct carbonate fuel cell, a gas turbine and a steam cycle, which generates power at a LHV efficiency in excess of 70 percent. This new system is called a Tandem Technology Cycle (TTC). In a TTC operating on natural gas fuel, 95 percent of themore » fuel is mixed with recycled fuel cell anode exhaust, providing water for the reforming of the fuel, and flows to a direct carbonate fuel cell system which generates 72 percent of the power. The portion of the fuel cell anode exhaust which is not recycled, is burned and heat is transferred to the compressed air from a gas turbine, raising its temperature to 1800{degrees}F. The stream is then heated to 2000{degrees}F in the gas turbine burner and expands through the turbine generating 13 percent of the power. Half the exhaust from the gas turbine flows to the anode exhaust burner, and the remainder flows to the fuel cell cathodes providing the O{sub 2} and CO{sub 2} needed in the electrochemical reaction. Exhaust from the fuel cells flows to a steam system which includes a heat recovery steam generator and stages steam turbine which generates 15 percent of the TTC system power. Studies of the TTC for 200-MW and 20-MW size plants quantified performance, emissions and cost-of-electricity, and compared the characteristics of the TTC to gas turbine combined cycles. A 200-MW TTC plant has an efficiency of 72.6 percent, and is relatively insensitive to ambient temperature, but requires a heat exchanger capable of 2000{degrees}F. The estimated cost of electricity is 45.8 mills/kWhr which is not competitive with a combined cycle in installations where fuel cost is under $5.8/MMBtu.« less
  • Carbonate fuel cells developed in commercial 2.85 MW size, have an efficiency of 57.9%. Studies of higher efficiency hybrid power cycles were conducted to identify an economically competitive system and an efficiency over 65%. A hybrid power cycle was identified that includes a direct carbonate fuel cell, a gas turbine, and a steam cycle, which generates power at a LHV efficiency over 70%; it is called a Tandem Technology Cycle (TTC). In a TTC operating on natural gas fuel, 95% of the fuel is mixed with recycled fuel cell anode exhaust, providing water for reforming the fuel, and flows tomore » a direct carbonate fuel cell system which generates 72% of the power. The portion of fuel cell anode exhaust not recycled, is burned and heat is transferred to compressed air from a gas turbine, heating it to 1800 F. The stream is then heated to 2000 F in gas turbine burner and expands through the turbine generating 13% of the power. Half the gas turbine exhaust flows to anode exhaust burner and the rest flows to the fuel cell cathodes providing the O2 and CO2 needed in the electrochemical reaction. Studies of the TTC for 200 and 20 MW size plants quantified performance, emissions and cost-of-electricity, and compared the TTC to gas turbine combined cycles. A 200-MW TTC plant has an efficiency of 72.6%; estimated cost of electricity is 45.8 mills/kWhr. A 20-MW TTC plant has an efficiency of 65.2% and a cost of electricity of 50 mills/kWhr.« less
  • FuelCell Energy, INC. (FCE) is currently involved in the design of ultra high efficiency power plants under a cooperative agreement (DE-FC26-00NT40) managed by the National Energy Technology Laboratory (NETL) as part of the DOE's Vision 21 program. Under this project, FCE is developing a fuel cell/turbine hybrid system that integrates the atmospheric pressure Direct FuelCell{reg_sign} (DFC{reg_sign}) with an unfired Brayton cycle utilizing indirect heat recovery from the power plant. Features of the DFC/T{trademark} system include: high efficiency, minimal emissions, simplicity in design, direct reforming internal to the fuel cell, no pressurization of the fuel cell, independent operating pressure of themore » fuel cell and turbine, and potential cost competitiveness with existing combined cycle power plants at much smaller sizes. Objectives of the Vision 21 Program include developing power plants that will generate electricity with net efficiencies approaching 75 percent (with natural gas), while producing sulfur and nitrogen oxide emissions of less than 0.01 lb/million BTU. These goals are significant improvements over conventional power plants, which are 35-60 percent efficient and produce emissions of 0.07 to 0.3 lb/million BTU of sulfur and nitrogen oxides. The nitrogen oxide and sulfur emissions from the DFC/T system are anticipated to be better than the Vision 21 goals due to the non-combustion features of the DFC/T power plant. The expected high efficiency of the DFC/T will also result in a 40-50 percent reduction in carbon dioxide emissions compared to conventional power plants. To date, the R&D efforts have resulted in significant progress including proof-of-concept tests of a sub-scale power plant built around a state-of-the-art DFC stack integrated with a modified Capstone Model 330 Microturbine. The objectives of this effort are to investigate the integration aspects of the fuel cell and turbine and to obtain design information and operational data that will be utilized in the design of a 40-MW high efficiency Vision 21 power plant. Additionally, these tests are providing the valuable insight for DFC/Turbine power plant potential for load following, increased reliability, and enhanced operability.« less