Evaluation of Cooling, Heating, and Power (CHP) Systems Based on Building Energy-Rating

Cooling, Heating and Power (CHP) systems are a form of distributed generation that uses internal combustion prime-power engines to generate electricity while recovering heat for other uses. CHP is a promising technology for increasing energy efficiency through the use of distributed electric and thermal energy recovery-delivery systems at or near end-user sites. Although this technology seems to be economically feasible, the evaluation and comparison of CHP systems cannot be restricted to economical considerations only. Standard economic analysis, such as life cycle economic analysis, does not take in consideration all the benefits that can be obtained from this technology. For this reason, several aspects to perform a non-conventional evaluation of CHP systems have to be considered. Among the aspects to be included in a non-conventional evaluation are: power reliability, power quality, environmental quality, energy-efficient buildings, fuel source flexibility, brand and marketing benefits, protection from electric rate hikes, and benefits from promoting energy management practices. Some benefits of these non-economical evaluations can be transferred into an economic evaluation but others give intangible potential to the technology. This paper focus on a non-conventional evaluation based on energy-efficient buildings, which is associated to energy conservation and improvement of the building energy performance rating for government energy programs like Energy Star and Leadership in Energy and Environmental Design (LEED). Results show that the use of CHP systems could improve the Energy Star Rating in more than 50 points. The Energy Star Rating is significant on the LEED Rating as a building can score up to 10 points of the 23 available in the Energy & Atmosphere category on energy efficiency alone. As much as 8 points can be obtained in this category due to the Energy Star rating increment from the use of CHP systems. Clearly the use of CHP systems will help building owners to reach the benefits from these energy programs while improving the overall energy use and energy cost.