There are many relatively simple ways that owners can increase the energy efficiency of their home.As much as half of the energy used in homes goes toward heating and cooling. The following are a few ways that energy bills can be reduced through adjustments to the heating and cooling systems:

• Install a ceiling fan.
• Periodically replace air filters in air conditioners and heaters.
• Set thermostats to an appropriate temperature. In wintertime, they should be turned down at night and when no one is home. In most homes, about 2% of the heating bill will be saved for each degree that the thermostat is lowered for at least eight hours each day. Turning down the thermostat from 75° F to 70° F, for example, saves about 10% on heating costs. Reverse the process in summertime.
• Install a programmable thermostat. A programmable thermostat saves money by allowing heating and cooling appliances to be automatically turned down during times that no one is home and at night. Programmable thermostats may save up to $150 per year in energy costs.
• Curtains drawn over windows will better insulate the room.

Sealing and insulating your home is one of the most cost-effective ways to make a home more comfortable and energy-efficient. The following are some common places where leakage may occur:

• Electrical receptacles/outlets
• Mail slots
• Around pipes and wires
• Wall- or window-mounted air conditioners
• Attic hatches
• Fireplace dampers
• Inadequate weather stripping around doors
• Baseboards
• Window frames
• Switch plates

Homeowners can perform a variety of repairs and maintenance to their attics that save them money on cooling and heating, such as: 

• Plug the large holes. Locations in the attic where leakage is most likely to be the greatest are where walls meet the attic floor, behind and under attic knee walls, and in dropped-ceiling areas.
• Seal the small holes. You can easily do this by looking for areas where the insulation is darkened. Darkened insulation is a result of dusty interior air being filtered by insulation before leaking through small holes in the building envelope. In cold weather, you may see frosty areas in the insulation caused by warm, moist air condensing and then freezing as it hits the cold attic air. In warmer weather, you'll find water staining in these same areas. Use expanding foam or caulk to seal the openings around plumbing vent pipes and electrical wires. Cover the areas with insulation after the caulk is dry.
• Seal up the attic access panel with weather stripping. You can cut a piece of fiberglass or rigid foamboard insulation in the same size as the attic hatch and glue it to the back of the attic access panel. If you have pull-down attic stairs or an attic door, these should be sealed in a similar manner.

About one-third of the home's total heat loss usually occurs through windows and doors. The following are ways to reduce energy lost through windows and doors:

• Seal all window edges and cracks with rope caulk. This is the cheapest and simplest option.
• Windows can be weather stripped with a special lining that is inserted between the window and the frame. For doors, apply weather stripping around the whole perimeter to ensure a tight seal when they're closed. Install quality door sweeps on the bottom of the doors, if they aren't already in place.
• Install storm windows at windows with only single panes. A removable glass frame can be installed over an existing window.
• If existing windows have rotted or damaged wood, cracked glass, missing putty, poorly fitting sashes, or locks that don't work, they should be repaired or replaced.

Homeowners who take the initiative to make these changes usually discover that the energy savings are more than worth the effort. InterNACHI home inspectors can make this process much easier because they can perform a more comprehensive assessment of energy-savings potential than the average homeowner can.

Taken from "10 Easy Ways to Save Energy in Your Home" by Nick Gromicko, Ben Gromicko, Rob London and Kenton Shepard