Green Cars

Vehicle Use: Driving Practices

Your driving practices can significantly affect the environmental performance of your vehicle, regardless of the type of vehicle you own.


To maximize fuel economy and minimize the emissions your vehicle generates, we recommend the following three simple tricks.

  1. Drive less by choosing alternative modes of transportation.
    The best way you can reduce your contribution to air and water pollution, traffic congestion, and the depletion of non-renewable natural resources is by limiting the number of vehicle miles you drive. This can be accomplished by choosing clean transportation options such as biking and walking, carpooling, and efficient public transportation whenever possible. Check out our
    Tailpipe Tally to estimate your contribution to CO2 emissions and global warming by driving your car or truck.

    Biking and walking are the healthiest transportation options. While completely eliminating vehicle exhaust, they offer an easy way to get outside and exercise, and an opportunity for you to communicate with neighbors and other members of your community. In 20 minutes you can walk one mile or bike four miles. In the United States, nearly 64 percent of all daily trips are within easy biking distance; 44 percent of all trips to work and 75 percent of all shopping trips are 5 miles or less in distance.

    Carpooling can significantly reduce transportation emissions while conserving gasoline. EPA estimates suggest that a two-person carpool can reduce overall emissions by 50 percent and fuel consumption by 33 percent, when compared to individual driving and average fleet efficiencies.

    Shifting people away from driving alone to sharing rides, walking, bicycling, or taking public transportation may require the support of politicians, regulators, and employers. "Modal" shifts such as these are best supported by comprehensive land-use changes, and policies that encourage more environmentally benign modes of transportation.

  2. Avoid aggressive driving habits.
    Aggressive driving habits can dramatically increase emissions while decreasing your fuel economy. Jack-rabbit accelerations, excessive speed, and hauling heavy loads are only a few such aggressive driving behaviors.

    Accelerate and decelerate smoothly and gradually. Jack-rabbit accelerations consume up to 50 percent more fuel and generate one-hundred times (100x) as much carbon monoxide and hydrocarbon emissions when compared to slow, steady accelerations. In traffic, anticipate stops and starts for traffic lights and changing traffic speeds to maintain a constant speed and minimize brake use.

    Avoid using your vehicle's air conditioning whenever possible. The use of air conditioning can decrease fuel efficiency by as much as 12 percent in stop-and-go traffic.

    Avoid excessive speeds. You can improve your gas mileage 15 to 20 percent by driving 55 miles per hour (mph) rather than 65 mph. Some estimates suggest that fuel economy decreases by two percent (2%) for each mph increase in speed over 55 mph; above 65 mph, the rate of decrease is even greater.

    Avoid hauling unnecessary loads; extra weight decreases fuel economy and increases pollutant emissions. For each additional 100 pounds of weight, fuel economy decreases by 0.5 miles per gallon. Place luggage and cargo inside rather than on the roof or trunk of the vehicle to maintain an aerodynamic profile and minimize drag.

    Avoid hauling unnecessary loads; extra weight decreases fuel economy and increases pollutant emissions. For each additional 100 pounds of weight, fuel economy decreases by 0.5 miles per gallon. Place luggage and cargo inside rather than on the roof or trunk of the vehicle to maintain an aerodynamic profile and minimize drag.

  3. Plan your trips and reduce the time your vehicle runs.
    To conserve fuel and reduce the emissions generated during vehicle use, plan your daily trips to minimize the time a vehicle runs. Combining errands and turning off your vehicle rather than letting it idle are two effective strategies. With today's oil formulations, there is no need to warm-up your car before you drive; simply start it proceed gradually.

    Much of the pollution your vehicle generates occurs during cold starts, when the engine has been off for 90 minutes or longer. Combining errands keeps an engine warm, and reduces cold-start emissions. Furthermore, by parking once in a central location and walking to accomplish several errands, you lessen the total distance traveled, and minimize the number of times you start your engine.

 

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