0

Full Content is available to subscribers

Subscribe/Learn More  >

Comparison of Molten Carbonate and Solid Oxide Fuel Cells for Integration in a Hybrid System for Cogeneration or Tri-Generation

[+] Author Affiliations
Georgia C. Karvountzi, Paul F. Duby

Columbia University

Clifford M. Price

Tractebel Power, Inc.

Paper No. IMECE2004-59927, pp. 139-150; 12 pages
doi:10.1115/IMECE2004-59927
From:
  • ASME 2004 International Mechanical Engineering Congress and Exposition
  • Advanced Energy Systems
  • Anaheim, California, USA, November 13 – 19, 2004
  • Conference Sponsors: Advanced Energy Systems Division
  • ISBN: 0-7918-4701-2 | eISBN: 0-7918-4178-2, 0-7918-4179-0, 0-7918-4180-4
  • Copyright © 2004 by ASME

abstract

High temperature fuel cells, such as molten carbonate fuel cells (MCFC) and solid oxide fuel cells (SOFC) can be integrated in a hybrid cycle with a gas turbine and a steam turbine and achieve overall lower heating value (LHV) efficiencies of about 70%. A hybrid cycle designed for cogeneration or tri-generation applications could lead to even higher overall LHV efficiencies. Tri-generation is the combined generation of power, heat and cooling from the same fuel source. The purpose of the present paper is to compare the performance of a 20MW MCFC system and a 20MW tubular SOFC system and assess their potential to cogeneration and tri-generation applications. The system includes a fuel cell, a gas turbine, a multiple pressure heat recovery steam generator (HRSG), a steam turbine and an absorption chiller (for cooling). The systems were designed and sized using GatecycleTM heat balance software by GE Enter Software, LLC. In order to optimize each system we developed curves showing LHV “electric” and “cogeneration” efficiency versus power for different ratios of “MCFC and SOFC fuel cell-to-gas turbines size.” At atmospheric pressure and at 675°C (1247°F) the 20MW MCFC system achieves “electric” efficiency of 69.5%. The SOFC at the same pressure and at 980°C achieves 67.3% “electric” efficiency. The MCFC alone is more efficient (58%) than the SOFC alone (56%). However the SOFC produces more heat than the MCFC leading to slightly higher cogeneration and tri-generation efficiencies. Pressurized operation at 9atm boosts the performance of the SOFC system to higher efficiencies (70.5%). Pressurized operation is problematic for the MCFC due to increased cathode corrosion leading to cathode dissolution as well as sealant and interconnection problems. However we can pressurize the MCFC system independently of the fuel cell with the integration of a gas turbine with a compressor pressure ratio of 10 to 16. Thus we achieve efficiencies close to 69%. In conclusion SOFC is more efficiently integrated in a hybrid configuration with gas turbine and a steam turbine for trigeneration applications when pressurized. MCFC is more efficiently integrated at atmospheric and pressures below 6 atm.

Copyright © 2004 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In