Methodology to perform a non-conventional evaluation of cooling, heating, and power systems

Abstract

Cooling, heating, and power (CHP) is a distributed generation technology that can provide electricity and heat while improving the overall thermal energy efficiency of a building. The evaluation and comparison of this technology versus conventional technologies cannot be limited to economical considerations only. Therefore, a non-conventional evaluation, based on non-economical aspects, is necessary to show the additional benefits that can be obtained from the CHP technology. A non-conventional evaluation includes aspects such as: environmental quality, energy-efficient buildings, power reliability, power quality, fuel source flexibility, etc. Some benefits of these non-conventional evaluations can be factored into an economic evaluation but others give intangible potential to the technology. The current paper presents a methodology to evaluate CHP systems based on two non-conventional aspects: energy-efficient buildings and emission of pollutants. Using the methodology described in the current paper it can be demonstrated that the use of CHP systems could improve the Energy Star rating of a building in more than 50 points. The improvement on the Energy Star rating is significant on the Leadership in Energy and Environmental Design rating as a building can score up to ten points of the 23 available in the energy and atmosphere category on energy efficiency alone. As much as eight points can be obtained in this category due to the Energy Star rating increment from the use of CHP systems. Also, using the proposed methodology it can be demonstrated that CHP systems have the ability to significantly reduce emission of pollutants. For carbon dioxide a reduction around 50 per cent can be reached, for nitrogen oxides the reduction can be in the order of 75 per cent, while for sulphur dioxide the reduction is higher than 90 per cent.