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Title: Detailed thermodynamic investigation of an ICE-driven, natural gas-fueled, 1 kWe micro-CHP generator

Here, the purpose of this work is to record the baseline performance of a state-of-the-art micro-combined heat and power (mCHP) system. A second goal of this work is to provide detailed thermodynamic first and second law performance measurements of the internal combustion engine and generator subsystems. A global technology survey was conducted to identify the leading mCHP systems in the 1 kW electric range. The Honda ECOWILL was identified as the state-of-the-art system in the United States, and an unused unit was procured. The ECOWILL underwent round-robin performance testing at three independent laboratories. First law (energy) and second law (exergy) analyses were conducted on the steady state data. Analysis revealed the ECOWILL operated at a first law electrical efficiency of 23.5 ± 0.4% and a utilization factor of 74.5 ± 3.2%. The primary energy loss was heat transfer from the device, followed by chemical and thermal energy in the exhaust stack. The second law analysis showed the ECOWILL operated at a second law electrical efficiency of 23.1 ± 0.4% and total (including exergy in both the electrical and recovered waste heat streams) second law efficiency of 30.2 ± 2.3%. Key areas of exergy destruction were, in decreasing magnitude, heat transfer,more » combustion irreversibility, and generator and friction losses.« less
ORCiD logo [1] ; ORCiD logo [2] ; ORCiD logo [2] ; ORCiD logo [2] ; ORCiD logo [2] ; ORCiD logo [2] ;  [3] ;  [1]
  1. Oregon State Univ., Bend, OR (United States)
  2. Oak Ridge National Lab. (ORNL), Knoxville, TN (United States)
  3. Booz Allen Hamilton, Washington, D.C. (United States)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Energy Conversion and Management
Additional Journal Information:
Journal Volume: 166; Journal Issue: C; Journal ID: ISSN 0196-8904
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
USDOE Advanced Research Projects Agency - Energy (ARPA-E)
Country of Publication:
United States
42 ENGINEERING; Residential cogeneration; Micro combined heat and power; Thermodynamic analysis; Internal combustion engine; Exergy analysis; CHP
OSTI Identifier: