The prospect of dizzying energy bills, maxed-out power grids, and killer heat waves poses a dilemma for the eco-minded. Crank up the AC, and you'll burn through countless kilowatts -- not to mention your budget. Listen to your green conscience, and you'll pay with sweat.

But when you maximize the efficiency of your home's cooling system and adopt smart, low-cost strategies, you can save money and still beat the heat. In fact, by eliminating wasteful habits and power guzzlers, you could cool your home with up to 50 percent less energy and save more than $400 on annual utilities. With 100 million tons of heat-trapping CO2 emitted every year as a result of residential air-conditioning, your new habits will amount to nothing less than a step toward global cooling.

Window Units

They can't compete with central air's efficiency for whole-house cooling, so use window units only in contained areas. For maximum comfort, keep fan speed on high except on the most humid days, when you'll want low speed to remove more moisture. If it's time for a new unit, choose one with the Energy Star label for greatest efficiency; since oversized units tend to waste energy, select an AC sized for the space you intend to cool (visit for guidelines).


Give AC a rest when you're away for even a few hours. Set programmable thermostats to kick in half an hour before you return home unless you have heat-sensitive indoor pets. Cranking the thermostat to penguin-worthy temperatures won't cool the house faster, since AC works at full throttle until a set temperature is reached. With every degree you lower it, cooling costs increase by about 7 percent.



Unplug small appliances whenever you can. Computers, cell phone chargers, and other electronics often continue to use power -- and radiate heat -- even when turned off. To simplify, plug items into a power strip that you can use as a master switch.



Incandescent bulbs put more energy into generating heat than light, so replace high-use bulbs with compact fluorescent lightbulbs (CFLs). They burn cool and bright with only a third of the power required by incandescents.


Window and Fans

Position a fan to blow air out a window. But if you're lucky enough to have a strong wind, set the fan to blow in the same direction to maximize air flow. Close nearby windows to keep exhausted air from flowing back in and open those on the other side of the house (ideally in cool, shaded areas). In a multilevel home, place the fan in a top-floor window and open windows on lower floors, where air is cooler. For windows that catch direct sun, use blackout blinds or heavy drapes to minimize solar heat gain.


Central Air

If you have central AC, schedule annual servicing. Visits cost up to $100, but repairs and tune-ups that increase efficiency soon pay for themselves. If you want to invest in a new system, look for a seasonal energy efficiency rating (SEER) of at least 14 to qualify for up to $300 in tax credits. But take note: Credits only apply to home improvements made through the end of this year. Tax credit or no, you stand to earn significant savings by replacing a system sold in the 1990s, which can guzzle up to 40 percent more energy than today's most efficient systems.



Run appliances such as clothes dryers and dishwashers at night to avoid peak energy rates and the humid heat they generate. Excess humidity is more than uncomfortable -- it can also be expensive, since air conditioners use extra energy to process the moisture.



Take advantage of summer weather and cook outdoors, as prolonged baking or stovetop cooking makes AC work overtime. Too muggy outside? Use a microwave or toaster oven, which use less energy and generate less heat. When you need to use a burner, keep pots covered to cook food faster and minimize humid heat in the kitchen.



Don't keep extra refrigerators and freezers in unconditioned spaces, such as garages, where heat tends to build up. Save more energy by opting for a chest freezer, which loses less cold air when opened. Keep all freezers relatively full for maximum efficiency.


Ceiling Fans

Partner ceiling fans with AC to make rooms feel at least 4 degrees cooler (so you can raise the thermostat and save energy without feeling the heat). Turn fans off when you leave the room; windchill makes you feel cooler but doesn't drop room temperature or ventilate the house. Opt for counterclockwise rotation, which pulls hot air up and away.

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Comments (1)

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December 31, 2018
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