燃料经济性

Fuel Economy燃料经济性

Fuel economy in automobiles，refers to the fuel efficiency relationship between distance traveled by an automobile and the amount of fuel consumed．Fuel economy is calculated by themiles per gallon(mpg) or kilometers per liter(km/l) of fuel thata vehicle consumes．Themore distance per tank of fuel，the better the fuel economy．

Through the 1950s and 1960s in the United States，fuelwas relatively cheap and gasoline engines were not very fuel-efficient．This trend gave way to smaller imported cars in the 1970s，particularly after the gasoline shortage in 1976 when gasoline prices started their uphill climb．Today，consumers are struck not only by the exorbitant prices at the pump but also by a threatened shortage of fossil fuels．Combine thiswith continued unrest in the Middle Eastand it's easy to seewhy fuel economy has become a central issue to consumers．

Through the years，many engine designs have attempted to improve fuel economy without sacrificing power．Today's hybrid vehicles are themost recent example．Hybrids compliment a gasoline engine with battery power for use in city driving，where speeds are not excessive and frequent stopsand-starts are amajor cause of poor fuel economy．When the driver hits the highway，the engine switches from battery power to standard gasoline power．Hence，hybrids get better fuel economy in the city than on the highway．

For example，the fuel economy for the2006 Ford Escape 4WD SUV is rated at33mpg for city driving(14 km/l) and 29mpg on the highway(12 km/l)．The 2006 Toyota Prius is touted at 60mpg in the city(25 km/l) and 51mpg on the highway(21 km/l)．Compare this to a standard gasoline-only engine，and the fuel economy is double to triple．

Regardless of the type of vehicle being driven，there are some things every driver can do to improve fuel economy．Experts recommend driving in a controlled manner at the speed limit，avoiding sudden starts and stops．Build momentum easily from a green light，and coast to stops．

Extra weight in the car also cuts down on fuel economy．Many people carry golf clubs or other heavy items in the trunk for no reason，or use the rear seatas a storage area．When vacationing，try to carry everything inside the vehicle rather than using a roof rack．Roof racks create wind resistance that reduces fuel economy．

Regularmaintenance of a car also improves fuel economy．Be sure tires are inflated to the correct pounds per square inch(PSI)．The steering wheel should not pull to the left or right when driving on a flat，straight road．If constant pressure is required on the steering wheel to keep the vehiclemoving straight ahead，it likely needs a front-end alignment．Both issues impact fuel economy by creating added resistance against the pavement．The engine should also be tuned and running properly．

Gasoline expands in heat，so to get your money's worth，try to purchase fuel during the coolest part of the day．For those in warm climates，thismightmean a visit to the pump early in the morning after the underground tanks have had a chance to cool overnight．Also try to combine short trips，as the engine runsmore efficiently when warm．If you'll be idling oneminute or longer in a standard gasoline powered vehicle，cut the engine．This savesmoney at railroad crossings，when chatting out the window，or when picking up passengers．

Following these tips should help to improve fuel economy．When it comes time to replace your vehicle，consider fuel-saving models like hybrids．