Trade-linked Canada–United States household environmental impact analysis of energy use and greenhouse gas emissions

We compare energy use and greenhouse gas (GHG) emissions associated with total household expenditures and activities in Canada and US in 1997, the first detailed estimate of environmental burdens for Canadian households. We estimate direct burdens from published government data and indirect burdens using an industry-by-commodity, bi-national economic input–output life cycle assessment model developed in this study. Comparing 30 expenditure and two activity categories, per capita US household expenditures were 70% higher, while per capita household energy use and GHG emissions were only 10% and 44% higher, respectively. Energy use/dollar of expenditure was higher in most Canadian categories, while the average ratio of GHG emissions/energy use was higher in the US (65 vs 50 kg Eq. CO2/GJ) due largely to a higher proportion of electricity from nonrenewable sources. Indirect environmental burdens represented 63–69% of total burdens and 62–70% of total burdens were associated with household operation and transportation. Key drivers of differences between energy profiles were: higher per capita electricity use by Canadian households, and higher US household private health care expenditures and motor fuel use. Energy-intensive production for export represented a higher proportion of Canadian production, resulting in less agreement between consumption and production-based analyses for Canada than US.