Integrating Air Pollution, Climate Change, and Economics in a Risk-Based Life-Cycle Analysis: A Case Study of Residential Insulation

ABSTRACT One of the ways in which risk assessment can inform life-cycle analysis (LCA) is by providing a mechanism to translate midpoint categories into common endpoints. Although this analytical step is complex and often highly uncertain, it can allow for prioritization among disparate midpoints and subsequent analytical refinements focused on the endpoints that dominate policy decisions. In this article, we present an approach to address three widely differing impact categories—particulate matter air pollution, greenhouse gas emissions, and personal income. We use the case of increased residential insulation as a measure to reduce energy consumption, which implies economic and public health tradeoffs across all three categories. We apply previously developed models that combined input-output LCA and risk assessment to address public health impacts from particulate matter, and extend the framework to address greenhouse gases and the public health consequences of changes in income. For a hypothetical loan program applied to both new and existing single-family homes, we find a payback period of approximately one year for the particulate matter and greenhouse gas–related midpoints and endpoints, with the structure of the loan implying that no economic payback is required. Our central estimates for avoided disability adjusted life years (DALYs) for a 50-year period are approximately 200,000 for particulate matter, 900,000 for greenhouse gases, and 300,000 for income changes, although values are highly dependent on discount rates and other model assumptions. We conclude that all three impact categories are potentially significant in this case, indicating that analytical refinements should be considered for all three impact categories to reduce model uncertainties. Our study demonstrates how LCA and risk assessment can work together in a framework that includes multiple impact categories, aiding in the evaluation of the net impacts of an energy policy change on society.