Estimation of Comparative Life Cycle Costs and Greenhouse Gas Emissions of Residential Brownfield and Greenfield Developments

Abstract

This paper describes an approach to estimate life cycle costs and greenhouse gas emissions for residential brownfield and greenfield developments. The approach has been implemented in a spreadsheet estimation model that can be used to estimate the comparative life cycle costs and greenhouse gas emissions of major elements of residential brownfield redevelopments. The spreadsheet is available for download at http://www.cmu.edu/steinbrenner/brownfields/index.html. The estimation model includes default values and ranges based on a sample of United States residential brownfield and greenfield developments and other literature sources. Model users can enter information about their own developments and compare life cycle costs and emissions with the sample for individual characteristics. Five major characteristics are included for the life cycle assessment of brownfields compared with greenfields, including brownfield remediation, residential building construction, infrastructure costs, residential building utilities and maintenance, and resident travel. Based upon the sample of brownfield and greenfield developments included, the brownfield developments tend to have lower average overall impacts due to lower travel costs associated with infill development closer to city centers despite costs associated with remediation. These averages show that a brownfield development can save each person $150 annually, compared with a greenfield development. Greenhouse gas emissions savings are an average of $1,200 kgCO2e per year per person. However, design decisions with respect to building type and density have large effects on overall development impacts for either brownfields or greenfields.