Hot weather actually can reduce your fuel consumption – at least if you follow some basic tips.
“Under very hot conditions, AC can reduce a conventional vehicle’s fuel economy by more than 25%,” notes new guidelines posted on Fueleconomy.gov. The impact of running your air conditioning in a hybrid, plug-in or battery-electric vehicle “can be even larger on a percentage basis,” it notes.
In the days before AC , you’d likely keep your windows open while driving on a hot day. Today’s vehicles are designed to maximize aerodynamics and the added drag of leaving your window open is likely to use more fuel than running your AC.
Opening your windows to let out the excess heat when you start your car on a hot day is more efficient than trying to cool down what is essentially a greenhouse. Start the AC on after you get the engine running and have aired out the cabin. Air conditioning usually is more effective and efficient when you are moving.
Other recommendations from the DoE and other sources:
• Get a summer service check to make sure your car is in tune. It uses less fuel when it’s running efficiently;
• A tune-up doesn’t apply only to the engine. Make sure the AC system is checked and has the proper level of coolant to run most efficiently. Also make sure your radiator has enough antifreeze which, in summer, helps prevent boilover;
• When you park, look for a spot in the shade, or get a sunshade that can reflect or block the sun’s rays.
• If you own a plug-based vehicle, such as a Nissan Leaf or Chevrolet Volt, chances are you can pre-cool the cabin (and pre-heat it during the winter) while it’s still connected to its charger. That not only means it will be pleasant to climb into but that you’ll also maximize range.
• Using a warmer temperature setting for the AC will use less battery power.
• Driving at or under the speed limit can save as much as 33% of your fuel. Coasting to a stop, rather than slamming the brakes, can reduce your bills – while it also pays off to start out smoothly, rather than making jackrabbit starts when the light turns green.
• Tires can have a substantial impact on mileage, as much as 10% of your fuel economy. The AAA recommends regularly checking your tire to ensure their at the pressure recommended by the manufacturer or tire maker. It’s best to check in the morning, before temperatures rise and pressures increase. Road friction also increases pressure, so check before you begin your commute or start running errands.
• Compare fuel prices. Warehouse clubs and grocery stores often have some of the best prices.
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