Energy and Global Warming Impacts of HFC Refrigerants and Emerging Technologies

摘要

This report summarizes the results from the third phase of a project sponsored by the U.S. Department of Energy (DOE) and the Alternative Fluorocarbons Environmental Acceptability Study (AFEAS).1 The study is a comparative analysis of the global warming impacts of alternative technologies for refrigeration, air conditioning, and appliance insulation that could be commercialized during the phase-out of hydrochlorofluorocarbons (HCFCs) mandated under the Montreal Protocol. The analysis utilizes a systems approach to determine the overall contribution to global warming from an individual air conditioner, heat pump, or refrigeration system during its operating lifetime- a concept known as the 'total equivalent warming impact (TEWI).' Air conditioners, heat pumps, and refrigeration systems can affect global warming through the release of refrigerants and insulation blowing agents directly into the atmosphere and also through the release of carbon dioxide from the generation of electricity to power the system throughout its lifetime. The results of the TEWI analysis for refrigeration and air conditioning applications are presented in this report. The TEWI concept provides a useful tool in the assessment of various competing technologies. However, it is only one of many criteria that must be considered as illustrated in Fig. 1. Safety, health, and other environmental concerns, system initial and operating costs, regional energy considerations, and ease of maintenance are among other important factors that must be evaluated in the selection of the 'best technology' for any given application. Finally, TEWI is dependent on the electricity fuel mix in a given area; as such it should not be considered absolutely, but rather comparatively.