|
The main components of automobile exhaust are carbon dioxide (CO2) and water vapor (H2O). Carbon dioxide is the most important anthropogenic greenhouse gas (GHG) and the most significant Greenhouse Gas emitted in the U.S. (with 82-84% of all U.S. emissions).〔(July 1999 SBC Newsletter )〕 Increases in carbon dioxide concentration are due primarily to fossil fuel use and land-use change.〔 IPCC, ' .〕 The CO2 emission standards can be referred to the fuel or to the vehicle : *The European Union is moving towards fuel mandatory CO2 standards and USA has reflected it in the Greenhouse Gas Score. *There are information, but no mandatory, standards for CO2 limits in vehicle (engine) emissions, excepting some state regulations (i.e. California). See hybrid vehicles. CO2 mass emission in vehicles is measured in g/km (g/mi * 0.621371192 = g/km). == Low carbon fuel standard == Transportation accounts for forty percent of California's annual greenhouse gas emissions, and California relies on petroleum-based fuels for 96 percent of its transportation needs. The Californian Governor Arnold Schwarzenegger issued an Executive Order in January 2007 for California adopt a Low-Carbon Fuel Standard (LCFS). The LCFS requires oil refineries to ensure that the mix of fuel they sell in the California Market meets, on average, a declining target for greenhouse gas emissions measured in CO2-equivalent grams per unit of fuel energy sold. By 2020, the LCFS will produce a 10 % reduction in carbon intensity from production and use of transport fuels in California.〔(【引用サイトリンク】title=Low-Carbon Fuel Standard Program )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Low-carbon emission」の詳細全文を読む スポンサード リンク
|