Life cycle sustainability assessment of geothermal heating and cooling system: UIC case study

Abstract

This study presents a sustainability assessment of geothermal heating and cooling system of three buildings at the University of Illinois at Chicago - Grant, Lincoln, and Douglas Halls based upon the triple bottom line sustainability framework and presents a comparison between geothermal and conventional heating and cooling systems. Life cycle assessment (LCA) was performed to evaluate and quantify the environmental impacts for both geothermal and conventional systems. Similarly, economic impacts were evaluated by making a comparison between direct and indirect costs of both systems. Indirect costs were calculated using Stepwise 2006 incorporated in monetized LCA and compared that cost with social cost of carbon. Social impacts were quantified using Social Sustainability Evaluation Matrix (SSEM) which covers four major dimensions of society: social-individual, socio-institutional, socio-economic, and socio-environmental. An overall sustainability index for geothermal system and conventional system was calculated by evaluating environmental, economic, and social impacts using Integrated Value Model for Sustainability Assessment (MIVES) methodology. The results show that the geothermal heating and cooling system is more sustainable and environmentally friendly than the conventional system.