1. Check air filters each month to make sure they're clean, and change them at least once every three months. When dirt and dust build up, your system has to work overtime. Dirty air filters impede airflow and can drive up energy costs by as much as 20 percent.
2. Install a programmable thermostat. Lennox's Energy Star ComfortSense 7000 thermostat regulates temperatures so you don't have to worry about wasting energy on heating or air-conditioning while you're away. Lennox claims that, when programmed correctly, the system can cut energy costs by as much as $150 a year. Visit lennox.com.
3. Seal air leaks to keep conditioned air indoors. Replace old or damaged weather stripping around doors, windows, and attic hatches, and remember to shut the flue when the fireplace isn't in use. According to Energy Star, you can save up to 20 percent of your home's heating and cooling costs if you follow the program's Home Sealing guidelines. Visit energystar.gov for more information.
4. Install efficient heating and cooling systems. Consider the Seasonal Energy Efficiency Ratio (SEER), which measures the cooling efficiency of air-conditioners and heat pumps, and Annual Fuel Utilization Efficiency (AFUE), which measures systems' heat production relative to fuel expenditures. Look for a SEER rating of at least 14 on air-conditioning units; on furnaces, you want an AFUE of 90 percent or higher.
5. Swap incandescent bulbs for compact fluorescents (CFLs) in fixtures that are on more than three hours a day. Or replace old, high-wattage incandescents with 60- or 75-watt bulbs.
6. Turn off unnecessary lights. Install dimmers, motion sensors, or timers, especially outdoors.
7. Install Energy Star light fixtures. Sea Gull Lighting sells energy-efficient chandeliers and sconces, and vanity, outdoor, and recessed lighting. Visit seagulllighting.com.
8. Cover your water heater with an insulating jacket. Inexpensive and easy to install, it effectively reduces heat loss by 25 to 40 percent, according to the American Council for an Energy-Efficient Economy. Visit aceee.org.
9. Update your bath with low-flow showerheads and faucet aerators. Old faucets can deliver as much as 5 gallons of water per minute (gpm). Newer options use air to create pressure, ensuring you won't waste water. Delta Faucet Company's H2OKinetic faucets use 1.6 gpm, and Hansgrohe's Raindance AIR Bodyspray uses only 1 gpm. Visit deltafaucet.com or hansgrohe-usa.com.
10. Consider a tankless water heater. It supplies hot water on demand, rather than using energy to constantly heat a reservoir the way standard units do. Bosch offers indoor or outdoor gas-powered or electric models that, according to the company, deliver as much as 50 percent savings on utility costs. Visit boschhotwater.com.
11. Launder only full loads, and wash in cold water when possible. Use liquid detergent rather than powder, which is more difficult to dissolve in cold water. Look for specially formulated detergents such as Tide Coldwater or Seventh Generation Free & Clear. Visit tidecoldwater.com or seventhgeneration.com.
12. Buy Energy Star electronics and appliances, and unplug power adaptors and battery chargers for cell phones, laptops, and battery-powered tools when not in use. Remember, even inactive items can draw electricity. Visit energystar.gov for more information.