Heating and cooling systems typically are responsible for the greatest portion of home energy bills. Here are ways to stay comfortable and still save money…

Create more zones. Homes with heating and cooling “zones,” where one part of the house can be cooler or warmer than the other, are ideal for saving energy. If your home has a ducted forced-air heating-and-cooling system that wasn’t initially designed as a zoned system, dampers can be installed to create a similar effect. Consider hiring a professional to install in the key ducts a series of motorized dampers that direct heated or cooled air where it’s needed.

Cost: About $1,000, depending on the type of damper and ease of accessing ductwork.

Install room air-conditioning units. If you and your family spend several hours a day in one room, such as the living room, an air conditioner in a window or wall or a portable unit might help save money even if you have central air-conditioning. You can turn on one of these units instead of central air and save energy. A portable unit, which sits on the floor and can be easily moved, has a venting hose that is put in an open window, along with a temporary sealing device.

Cost: $120 to $600.

Install ceiling fans. Ceiling fan technology has improved considerably and can help you save as much as 30% off your air-conditioning bills by better circulating air. Look for the Energy Star designation for energy efficiency.

Cost: Between $80 and $500 or more per fan, plus installation.

Make ductwork more efficient. Researchers at University of Oregon found that central heating and cooling systems that use ductwork lose as much as 50% of their energy through leaky ductwork. Have ductwork inspected for leaks once every three years by a heating contractor. All connections should be properly sealed, preferably with metal-reinforced tape or mastic, a rubbery fiber-reinforced goo that is applied with a brush. Some homes have flexible ductwork with built-in fiberglass insulation. Rigid metal ductwork needs to be wrapped with fiberglass duct insulation. All are available on-line and at most home-improvement stores.

Another way to make your ducts efficient is to apply an aerosol sealant called Aeroseal, developed by Lawrence Berkeley National Laboratory and licensed by Carrier Aeroseal, LLC. This aerosol, which must be applied by a Carrier-approved contractor, seals leaks, reducing energy loss by as much as 90%. To find a contractor, go to www.aeroseal.com and click on “Locate Dealer.”

Cost of application: $300 to $1,800, depending on the size of your home.

Install heat-recovery ventilators (HRVs). These units get rid of air contaminants, such as cooking odors, cigarette smoke, dust and mold. HRVs also grab much of the heat or cold from that outgoing air and recycle it back into the house with the incoming fresh air, cutting energy costs. They are especially useful in tightly sealed homes.

Cost: Room-sized models run from $350 to $450… whole-house units can cost $1,500 or more, plus installation.

Related Articles