Ways to Lessen Your Air Conditioner Usage This Summer

When temperatures rise, people instinctively resort to air conditioning. But that comfort comes at a price: in 2005, for example, 91.4 million U.S. households consumed 258 billion kilowatt-hours of electricity running air conditioners, according to the Energy Information Administration. That translates to about $24 billion in energy costs and 171 million tons of global warming emissions.

To keep both you and the planet cooler, consider these energy-efficient alternatives:

Evaporative coolers, also known as “swamp” coolers, use a fan to draw outside air through water-saturated pads, making the incoming air 15ºF to 40ºF cooler. They work best in dry or desert climates with little humidity. Two-stage coolers, which first pass the air through a heat exchanger, are effective in areas where temperatures reach or exceed 100ºF. According to the U.S. Department of Energy (DOE), evaporative coolers use about 75 percent less energy than a central air conditioner and cost half as much to install, but because they can consume up to 15 gallons of water per day, their use might be restricted during water shortages.

Whole-house fans installed in the ceiling pull cool evening and morning air into the house, while forcing hot air out through the attic. They use just one-tenth the electricity of a comparably sized air conditioner. Because of the heavy volume of air flow, you may need to install additional attic vents.

Ceiling fans help circulate the air, making it feel cooler. You can even run a ceiling fan in conjunction with an air conditioner set 4ºF higher than you otherwise would, with no change in comfort and less energy use overall (especially when using an Energy Star-rated fan, which is up to 20 percent more efficient than a standard model). To move air effectively, fan blades should be 10 to 12 inches from the ceiling.

Passive cooling strategies are electricity-free ways to reduce the amount of heat entering your home. For example:

• Trees—Planting deciduous trees on the south side of your home can help block sunlight in the summer but allow it through in the winter. According to the DOE, trees can reduce the surrounding air temperature as much as 9ºF, and the air within their shade as much as 25ºF. Keeping an air conditioner in full shade can increase its efficiency up to 10 percent.
• Solar screens—This window-covering fabric blocks up to 90 percent of incoming solar heat without obscuring your view.
• Awnings—These can reduce solar heat gain by 77 percent on west-facing windows, according to the DOE.

If you do decide an air conditioner is necessary, buy an Energy Star-rated model sized for your needs. Switching every room air conditioner sold in the United States to Energy Star models would avoid 650,000 tons of global warming emissions—the equivalent of taking 115,000 cars off the road.

***article from Greentips, published by the Union of Concerned Scientists

DOE Announces up to $22 Million for Community Renewable Energy Projects

July 15, 2009, from the Michigan Public Service Commission

U.S. Department of Energy (DOE) Secretary Steven Chu today announced plans to provide up to $22 million from the American Recovery and Reinvestment Act to support the planning and installation of utility-scale community renewable energy projects in up to four communities nationwide. This funding opportunity directly supports the Obama Administration’s goals of developing clean, renewable energy supplies, and creating new jobs and economic opportunities.

“American families and businesses are struggling in a recession and an increasingly competitive global economy. The Recovery Act was designed to rescue the economy from the immediate dangers it faces while rebuilding its fundamentals, with an eye toward new industry and opportunity,” Secretary Chu said. “To help meet these challenges, the Recovery Act invests significant dollars to put people to work to spur a revolution in clean energy technologies.”

The DOE Office of Energy Efficiency and Renewable Energy (EERE) will provide technical assistance to selected recipients, including concepts, best practices, planning, financial approaches, policy guidance, and recognition to help communities rapidly plan and deploy utility-scale renewable energy systems that provide clean, reliable, and affordable energy supplies for their communities, while creating jobs and new economic development opportunities. The projects will demonstrate how multiple renewable energy technologies, including solar, wind, biomass, and geothermal systems, can be deployed at scale to supply clean energy to communities.

DOE anticipates each project will leverage significant investment, including public and private sector investment in renewable energy systems. The projects funded under this Funding Opportunity Announcement are expected to create jobs and avoid 50,000 tons of carbon dioxide annually.

Up to $22 million in DOE funding is available for these awards in fiscal year 2010. DOE anticipates making up to 4 awards totaling up to $21.45 million, and expects matching funds from public and private investment of $22 million or more.

Successful applicants will be awarded financial assistance to support the implementation of an integrated renewable energy deployment plan for a community, and the construction of renewable energy systems.

Completed applications are due September 3, 2009. DOE will select awardees by the end of November 2009. For more information, please visit the Recovery Act Web site.