(Real Simple) -- Make a few easy changes around the house for substantial savings.

To save money and energy, seal electrical outlets along the exterior walls of your home.

Seal sneaky leaks

Seal electrical outlets in the exterior walls of your house. Foam insulating gaskets (less than $1 each) "act as a barrier so conditioned air stays in, rather than leaking out," says Jonathan Passe of the Environmental Protection Agency.

Just unscrew the outlet cover, install the gasket, and replace the cover.

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Go with the flow

Install a high-performance showerhead. This uses 1½ gallons of water per minute (gpm) rather than 2½ gallons, the federal upper limit for new showerheads.

By switching from a 2½-gpm to a 1½-gpm model ($20 and up), a family of four (each person taking daily 10-minute showers) could save about $88 a year on water and energy costs with gas water heating and $135 a year with electric, according to figures from the Department of Energy Federal Energy Management Program.

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Swap out bulbs

Replace incandescent bulbs with CFLs (compact fluorescent lightbulbs).

A $10 CFL uses about a quarter of the wattage of an incandescent bulb, which amounts to more than $30 in savings per replaced bulb over the lifetime of the CFL (which averages 10,000 hours or 416 days).

"If every household in the United States replaced one incandescent bulb with a CFL," says Pablo Päster, a sustainability engineer based in San Francisco, California, "the energy savings would be the equivalent of shutting down one coal-fired power plant."

Be cool

Wash clothes in cold water.

You may already know that this saves energy, but do you know how much?

"Up to 90 percent of the cost of washing clothes comes from heating the water, so use hot water only for very dirty clothes," says Adam Gottlieb of the California Energy Commission.

Another tip: "Match the water level to the amount of clothes, or wait to wash full loads," suggests Clement. "The water savings can be enormous."

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Close (or open) your blinds

Leave blinds down on south-and west-facing windows on hot summer days to keep your space cool.

"This prevents the sun from warming your home and making your cooling system work harder," says Clement. "In winter, leave blinds up to allow the sun to help heat your home."

Upgrade your heating (and cooling) system

Install (and properly program) a programmable thermostat. The average household spends $2,200 annually on energy bills, and about half of that is for heating and cooling, says Vargas.

A programmable thermostat costs $50 to $80, is easy to install, and can save about $180 a year.

You can shave 2 percent off your heating (or cooling) bill for each degree you lower (or raise) the thermostat for at least eight hours a day while you're away from home or asleep, says Amanda Korane of the American Council for an Energy-Efficient Economy.

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