A recent paper in Environmental Science & Technology gives a nice breakdown of typical life-cycle GHG emissions of conventional vehicles, hybrid electric vehicles, and plug-in hybrids for specific operating conditions. The production emissions are about 35 g of CO2-eq/km traveled, for all of them (slightly more when battery production is included for the hybrids). The use phase dominates, ranging from 145 to 240 g CO2-eq/km (the higher emissions coming from conventional vehicles).
A life-cycle assessment of apparel products shows that 73% of the life-cycle energy use for a pair of men's polyester trousers is due to washing, drying and ironing. Similary, 80% of the energy use in a pack of men's cotton briefs is a result of the use phase (cotton uses more energy in the use phase per unit weight).
Life-cycle emissions for products that last some years and use energy throughout that period are likely to be dominated by the use phase (products such as cars, applicances, clothes, etc.). So, for consumers, switching to hybrid vehicles and purchasing fabrics that consume less energy in washing/drying are all critical steps. However, given the huge amounts of manufactured products in the economy, production and distribution emissions are still important to quantify and optimize from a manufacturing perspective. CO2 emissions for the industrial sector (from fossil fuel combustion) are significantly higher than for the residential sector in the US and second only to transportation.
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