Heating bills in the winter. Cooling bills in the summer. If we could just get the planet to stop wobbling so much we might save a lot of confusion.
Now we must ponder, once again, ways of keeping the house cool without blowing the budget on air conditioning.
There are several products on the market intended to cut cooling costs by blocking solar radiation that enters the house. Solar shades, screens and films fit over windows and either reflect or absorb solar heat that would otherwise enter through the glass and heat the house interior. They are sold through many hardware, houseware and department stores. Prices range from around $13- $35 per window, depending on size.
Consumer Reports tested different types and brands for its March 1979 issue. It found that most blocked about 75 percent of the sun's radiation and a similar amount of visible light; almost like putting a pair of dark sunglasses on your house. Consumer Reports found "no significant differences in overall quality," but there are differences in the appearance of each and how easily they can be installed and removed.
Films, thin sheets of plastic material, are often reflective and can give your house an odd, mirrored look. Once they are on the window, they do not come off again easily. If you live in a temperate climate, such as Washington's, the film also will reflect radiation during the winter, causing you to lose natural heat that helps keep down fuel bills during the colder months.
Shades catch solar rays as well, but only after they have already entered the house. Some radiation is reflected back out the window. Consumer Reports believes the rest of it, however, passes through the shade or is absorbed by the window, adding heat to the room.
Solar screening is installed outside over the window casement and can replace normal insect screens. They, too, either absorb or reflect the sun's rays. But they can be removed in the winter to permit natural solar heating.
The National Bureau of Standards (NBS) has published 20 tips for saving summer energy costs. Among the most helpful is its suggestion that homeowners consider purchasing a "whole house fan" to use alternately with central or room air conditioning.
The NBS last year tested the performance of the house fans in three houses in the Houston area. They are only the beginning, and the results cannot be applied to all types of houses everywhere in the country. The tests showed, however, that discriminating use of air conditioning and house fans can reduce energy bills.
The test houses were wood-frame ramblers with brick veneer. Air conditioning was turned on only when the outside temperature climbed above 82 degrees. When the temperature fell below that mark, the air conditioning was turned off and the house fan, which consumes considerably less energy, used instead. The NBS found that at 76 degrees the house fan cooled the house with two-thirds less energy than the air conditioner would have used.
House fans, priced at $160- $220, depending on size, and mounted in the ceiling or on the outside wall of the attic, cool the living area by drawing air through open windows and circulating it throughout the house.
They are not the same as attic fans, smaller and priced around $50, designed to ventilate the attic area. Although attic fans, operating at full capacity, can cut the amount of heat soaked up by ceilings and ducts, NBS tests showed they reduce cooling requirements at most by only 6 percent and usually by as little as 3 percent. Researchers concluded that attic fans actually use more energy than they save and do little to improve indoor comfort, though they are sometimes essential for eliminating attic moisture during the winter.
Some cool advice from NBS:
Open windows to catch cooler night breezes. If you use window fans, place them on the shaded side of the house. Turn the air conditioner thermostat up to 79 degrees. A six-degree difference in the setting can mean an 18 percent savings in fuel.
Use awnings, overhangs, trees and shrubs to shade windows. Blinds should be light in color and opaque.
Limit use of appliances and turn off lights. Flourescent tubes give more light for the buck and generate less heat.
Make sure the refrigerator door seals are tight and the condensing coils clean. Don't use the self-cleaner on the oven.
Use exhaust fans, rather than opening windows, to get rid of steam from cooking, bathing or washing, and close off rooms where the fans are being used, if the house is air conditioned.
Check the energy efficiency of the room air conditioner you plan to buy. For the amount of BTUs per hour you will need, multiply the square footage of the room times 30, if the wall is fully exposed to sun, or by 15, if the wall is shaded. To compare the energy efficiency of different models, divide the BTUs per hour by the number of watts it uses. The higher the resulting number, the less energy you will use to cool.
Check filters every 30-60 days and either clean or replace them.
Insulate around air-conditioning ducts and hot-water storage tanks. Weatherstrip around windows and doors and repair caulk cracks. Close and seal openings into the attic. Keep storm doors and windows in place while the air conditioning is on. CAPTION: Picture 1 and 2, Want to be cool? Add on a big porch like the vice president's. Or a great fountain like the one in the Biltmore House in Asheville, N.C.; Illustration, no caption