Programmable thermostats

Programmable thermostats can save you money by raising the air conditioning temperature when you're away and overnight. Whether you want a different setting for weekdays and weekends, or want to schedule settings for each day of the week, there's a model to fit every lifestyle. Set your thermostat to 78°F, and then program it to raise the temperature 7°F when you're away from home, and 4°F overnight. The only difference you'll notice is in lower cooling bills.

Skill level: Basic
It's easy to set your programmable thermostat by the season. Set it once in spring and once in fall.
Cost range: $25-$250
Programmable thermostats are available at home improvement retailers. Look for rebates through the manufacturer and Focus on Energy that can help defray your costs.
Savings: Up to $180 annually (includes heating)
Using a programmable thermostat to control your HVAC system can save you about 8% a year in energy costs.