According to the U.S. Department of Energy, the average family shells out about $1,500 annually for utilities. With energy prices steadily rising, that may soon seem like a bargain.

Want to really slash your utility bills? Concentrate on cutting the biggest energy hogs in your household -- heating and cooling, which collectively account for more than half of the typical home's energy tab (and much more during the extreme weather months).

To twist a timeless cliche: An ounce of prevention is worth a pound of sweat (or a few nights of shivering, depending on the time of year). Here are tips on helping your wallet weather the seasons by significantly slashing your utility bills.

Keep cool and save some cash
We've all heard it plenty of times: Turning up the thermostat keeps your cooling bill down. But there's no need to suffer in sweltering heat. Even modest adjustments can make a difference. Small things (like changing the filter and cleaning the coil) can increase your unit's original efficiency anywhere from 5% to 20% each year. But that's not the only way to crank up the summer savings.

  • Use your thermostat to dial down your bill: In the summer, energy pros say that each degree setting below 78 degrees increases your energy consumption by about 8%. And every degree you raise the thermostat equals 1% to 2% of savings on your summer cooling bill. A programmable thermostat makes it effortless to keep the house at a higher temp during the hours when you're not around to fiddle with the dial.
  • Use AC SPF: If you use a window unit, too much sun directly on your unit's outdoor heat exchanger can lower its efficiency as much as 10%. Keep it shaded with vegetation, without blocking the air flow (or the maintenance guy's way).
  • Embrace the darkness: The cats might not appreciate their view being blocked, but closing the curtains during the day (particularly on east- and west-facing windows) will keep the indoor temp down. Also, try to limit all heat-generating chores (laundry, dishwasher-running, baking) to nighttime.
  • Sacrifice the spare bedroom: If there are rooms (or entire wings) to the house that you don't use much, close the vents and shut the doors and concentrate your air conditioner's efforts on cooling the high-traffic areas instead.
  • Go with the flow: All AC operation manuals recommend cleaning or replacing your air filter at least once a month. Most filters cost less than a cappuccino, and a clean one can lower your AC's energy suck by 5% to 15%.
  • Keep your coolant: According to the Air Conditioning Contractors of America (ACCA), a system that's 10% low on coolant (or freon, or the "refrigerant charge") costs about 20% more to operate than a system that's fully loaded. (Leave the topping-off to the pros, since freon's a hazardous substance.) Additionally, low freon can cause the compressor to overheat and die early. That can result in a big-ticket repair bill if the compressor or condensing unit needs to be replaced.
  • Clean sweep: During an annual checkup, your AC pro can also look for buildup on the outdoor air conditioning and heating coils, and clean them. Ask them how to check and clean the indoor coil, too. Because the coil is moist during summertime, it attracts a lot of dust. The ACCA says that dirt buildup on the indoor coil is the most common cause of poor efficiency.
  • It IS the humidity!: Actually, it's the dehumidifier that's the problem. The folks at say that running your dehumidifier while the AC is on forces the air conditioner to work harder and runs up your utility bill. For window units, run the fan on "low" on humid days. The slower air flow through the cooling system will more efficiently cut the moisture. If you have central air and live in a humid climate, put your thermostat on "auto" instead of letting the fan run the entire time.
  • Keep a lid on it: Grandma was right about drafts being dangerous. Worn out (or nonexistent) weatherproofing can result in serious air leaks that can contribute to more than one-third of cooling costs. (Looks like plastic sheeting and duct tape are handy to have around.) About 30% of the heat in your house is absorbed through the roof. Vents and attic fans can help keep things circulating and prevent your bills from going through the ... well, you get it.
  • Maintenance matters: Ignore regular maintenance at your peril. Overlooking the small things (like changing the filter and cleaning the coil) can reduce your unit's original efficiency about 5% each year.
  • Big chill savings: Switching to a high-efficiency air conditioner, though costly, will probably put the most money back in your pocket over time -- cutting your energy use by 20% to 50%.

Stay toasty and still see savings
Heating your home efficiently can be boiled down to these major to-do's: insulating, sealing leaks, and maintaining your home -- all with the goal of maximizing your heating dollars.

Start your home energy audit with a DIY version at, and get an upgrade report that calculates your savings, your return on investment, and your payback time in key areas (heating, cooling, water heating, appliances, and lighting).

Bring your insulation up to snuff: Part of your sleuthing expedition should include eyeballing your insulation to make sure it's in good shape. Pay careful attention to your attic, crawl spaces, walls (check existing walls by removing an outlet cover and using a flashlight), and the underside of floors that are above unheated spaces. Consider purchasing special insulation materials designed for your water pipes and water heater.

Before you purchase insulation, consult a chart that shows you what type (graded in "R" levels) you'll need, depending on factors such as climate and the location in your home where the insulation will be placed. For a step-by-step guide, consult the Department of Energy's online fact sheet.

In many cases, you can install or replace old insulation yourself. However, if your insulation job is a complicated one -- for example, insulating between walls in an existing home, working around old electrical wiring, or replacing wet or damp insulation, which could signal a leak -- you may want to hire a contractor. Many insulation contractors will come estimate your home's insulation needs for free, giving you a chance to determine which jobs seem like "do-it-yourself" projects, and which need a professional touch.

If you're working in your attic (since heat rises, many folks start their insulation journey here), make sure there's proper ventilation. Do-it-yourselfers sometimes mistakenly assume that more is better and cover up natural airflow at the eaves. However, this actually makes the home less energy-efficient, and prone to roofing problems because of ice dams or moisture.

Keep the bad elements out (and the good ones in) with proper sealing: Ensuring that heat isn't leaking out through improperly sealed windows, doors, or other openings is another way to save big on your heating bills. You'll want to pay special attention to duct work (a major culprit for energy inefficiency), cracks around doorways and windows, fireplaces, and other miscellaneous openings like attic pull-downs or access holes. Caulk, foam, and window-sealing kits can all be found at your nearest home-improvement store.

To learn more, consult the Environmental Protection Agency's helpful online guide to detecting and sealing air leaks in your home.

Maintain your hermetically sealed sanctuary: Certain maintenance projects can enhance your energy efficiency when performed regularly. These include changing your furnace filters on schedule, having your duct work cleaned, and hiring a professional to "tune up" your heating system each year so it stays in peak working order.

Again, programming your thermostat (keeping it warmer during waking hours and cooler while you sleep) will also cut your monthly utility bills. Also, turn down the heat on your water heater if you have it set to "scald."

Reaping the returns
If you're in your home for the long haul, you may want to consider some longer-term measures to make your energy usage much more efficient. These might include replacing your windows and buying Energy Star appliances, household products that meet stringent energy efficiency guidelines set forth by the EPA and the U.S. Department of Energy.

As you can see, all it takes is a little effort to cut your utility bills. And the savings can make it well worth the effort.