Life-Cycle Assessment and Life-Cycle Cost as Collaborative Tools in Residential Heating System Selection

Abstract

Typically the selection of a residential heating system focuses on first costs rather than the economic or environmental life cycle consequences. The use of life cycle assessment and life cycle cost methodologies in the design phase provide additional criteria for consideration when selecting a residential heating system. A comparative case study of a gas forced air and radiant solar heating system was conducted for a 3,000 square foot house located in Fort Collins, Colorado, U.S.A. The initial results of an analysis of the life cycle assessment and the life cycle cost data indicated the gas forced air system was superior, both environmentally and economically. Further data analysis pinpointed solar radiant system components for replacement in an effort to reduce both life cycle environmental emissions and costs. This analysis resulted in a hybrid radiant system using a high-efficiency gas-fired boiler, a choice that lowered both the solar radiant system's costs and emissions. This new system had slightly lower environmental impacts than both the gas forced air system and solar radiant system. Unfortunately the hybrid system had less impact on the life cycle cost with the hybrid system substantially more expensive then the gas-forced air alternative.