0
RESEARCH PAPERS

Selection of Distributed Power-Generating Systems Based on Electric, Heating, and Cooling Loads

[+] Author and Article Information
Gregory J. Kowalski

Department of Mechanical and Industrial Engineering,  Northeastern University, Boston, MA 02115gkowal@coe.neu.edu

Mansour Zenouzi

Electromechanical Engineering Program, Department of Electronics & Mechanical,  Wentworth Institute of Technology, Boston, MA 02115zenouzim@wit.edu

J. Energy Resour. Technol 128(3), 168-178 (Mar 08, 2006) (11 pages) doi:10.1115/1.2213275 History: Received February 02, 2005; Revised March 08, 2006

A generalized thermodynamic model is developed to describe combined cooling, heating, and power generating systems. This model is based on reversible power generation and refrigeration devices with practical, irreversible heat exchanger processes. It provides information on a system’s performance and allows easy comparisons among different systems at different loading conditions. Using both the first and second laws as well as the carbon dioxide production rate allows one to make a first-order system assessment of its energy usage and environment impact. The consistency of the exergy destruction rate and the first law performance ensures that the thermodynamic system boundaries are correctly and completely defined. The importance of the total thermal load to the required power ratio (HLRP) as a scaling parameter is demonstrated. A number of trends for limited conditions can be delineated even though the reported results confirmed that generalized trends are not identifiable because of the systems’ complexities. The results demonstrate that the combined vapor compression∕absorption refrigeration has higher first law utilization factors and lower carbon dioxide production rate for systems with high refrigeration to total thermal load ratios for all HLRP values. Fuel cell systems outperform engine systems for large refrigeration load applications. An illustration of combining these results to an economic analysis is presented.

FIGURES IN THIS ARTICLE
<>
Copyright © 2006 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Schematic of the engine-powered cogeneration system

Grahic Jump Location
Figure 2

Details of the refrigeration subsystem. The heat-powered refrigeration cycle is shown on the left and the vapor compression refrigeration cycle on the right. Both are included in this figure to describe the combined cycle.

Grahic Jump Location
Figure 3

Schematic of the fuel cell with reformer system used in the cogeneration analysis

Grahic Jump Location
Figure 4

The energy utilization factor is graphed as a function of the total thermal load to power ratio for an engine-based cogeneration system. The total thermal load is refrigeration, CHR=1.0.

Grahic Jump Location
Figure 5

The exergy destruction rate per power as a function of the total thermal load to power ratio for an engine-based cogeneration system. The total thermal load is refrigeration, CHR=1.0.

Grahic Jump Location
Figure 6

The carbon dioxide production per power is graphed as a function of the total thermal load to power ratio for an engine-based cogeneration system. The total thermal load is refrigeration, CHR=1.0.

Grahic Jump Location
Figure 7

The energy utilization factor as a function of the total thermal load to power ratio for an engine-based cogeneration system with a vapor compression refrigeration subsystem. The no-cogeneration case is also shown.

Grahic Jump Location
Figure 8

The energy utilization factor is graphed as a function of the total thermal load to power ratio for an engine-based cogeneration system for a cooling total thermal load ratio of 0.2. The three different refrigeration subsystems and the no-cogeneration case are shown.

Grahic Jump Location
Figure 9

The energy utilization factor is graphed as a function of the total thermal load to power ratio for an engine-based cogeneration system for a cooling total thermal load ratio of 0.8. The three different refrigeration subsystems and the no-cogeneration case are shown.

Grahic Jump Location
Figure 10

The energy utilization factor is graphed as a function of the total thermal load to power ratio for a fuel-cell-based cogeneration system with a vapor compression refrigeration subsystem. Different values of the cooling to total thermal load ratio are shown. The no-cogeneration case is shown.

Grahic Jump Location
Figure 11

The energy utilization factor is graphed as a function of the total thermal load to power for different systems designs and load conditions

Tables

Errata

Discussions

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 Journal Articles
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