The energy joyride—that brief delusion of 20th-century man that the supply of cheap fuel was limitless—came to a sudden stop in 1973 with the Arab oil embargo and subsequent price rises. But long before then, farsighted individuals had been advocating a change to what have come to be called alternate energy sources: waterpower, wind power, solar energy, wood, and other nonfossil fuels. Conservation was one reason, saving money was another, but equally important were ecological considerations, for the growing use of oil and coal was polluting the earth, the air, and the oceans. Energy From Wood, Water, Wind, and Sun is both an overview and a detailed look at small-scale applications of these “new” sources of energy. The techniques needed to use them in the home are described as well as the methods for determining if a particular system—be it wood stove, waterwheel, windmill, or solar heater—makes good economic sense for the individual homeowner.

Making Your House Energy Efficient

Energy-Saving Measures That Cost Least

The most effective way to save money on fuel bills is to use less fuel. At one time this philosophy was taken as a matter of course in America. Heavy shutters helped homeowners keep their houses warm in winter, cool in summer. Shrubbery was planted with an eye to protecting the home from weather and not used merely for decoration. Chimneys ran through the center of the house rather than along the exterior. Homes were compact, not sprawling, and designed to draw family members together not only for conversation but also to share body heat. In many farm homes even animal heat was used occasionally by sharing living quarters with a goat or cow, or by housing large animals in a space alongside or beneath the family’s living quarters. The need to save fuel influenced customs and manners too. Bundling, the practice of permitting unmarried couples to occupy the same bed without undressing, allowed courtships to proceed with a minimal cost in firewood.With the advent of the energy crisis, many old practices are being revived. These techniques, when combined with modern insulation and weather stripping, allow us to immunize our homes against the vagaries of the weather to a degree unimagined by our ancestors.

Where heat leaks out and cold leaks in

Reducing Air Infiltration

Every house has gaps and cracks through which outdoor air can enter and indoor air escape. In most houses air exchange takes place at a rate of one to two changes in an hour. Inevitably, this turnover of air causes a substantial loss of heated air in wintertime.
Caulking and weather stripping are the basic means for reducing this loss. Properly applied, they can lessen the air exchange rate by 50 percent and cut fuel bills by 5 to 20 percent, depending on how leaky your house is.
Caulking is used to seal construction cracks in the body of the house, such as those between window frame and siding. The usual way to apply caulking is with a caulking gun loaded with a cartridge of caulking compound. When the trigger is pressed, a continuous bead of compound is squeezed out, like toothpaste from a tube. The compound is also sold in a ropelike strip that can be pressed into place. Caulking is not a modern development. In pioneer days homesteaders would plug leaky cabins with such materials as moss, mud, clay, and pitch-impregnated rope. Today’s caulking compounds are superior. They are easier to apply, last longer, and insulate better. Oil-based compounds are still very common. Others include acrylic latex types that permit cleanup with water before they set. Butyl compounds are more flexible and stick to more materials.
Weather stripping is used to seal gaps between moving parts, such as those between a window sash and frame, and at door closures. To minimize wear, match the weather stripping to the motion of the parts.For compressive contact, as in a door closing, use felt or foam. For a sliding motion select a tough plastic or metal strip. Whatever type you buy, be sure it is thick enough to fill the gap. Foam stripping is available with a wood backing or with a self-stick adhesive backing. Where considerable compression is likely, as in a front door closure gap, use an open-cell foam, such as urethane. For light compression use a closed-cell type, such as vinyl. Adhesive-backed weather stripping bonds best when the temperature is above 50°F. During cold weather warm the surface to which the stripping is to be applied with a heat lamp or hair dryer. In some cases inexpensive felt stripping can be used for sliding as well as compressive contact. Where sliding motion is involved, the felt must be mounted carefully so that contact pressure is adequate but not excessive, since friction shortens the felt’s useful working life. Felt stripping is usually held in place by tacks or staples. Wherever possible, with any type of stripping, make a trial fit with a short length before doing the complete job. Check that the seal is snug enough to block drafts but not so tight that the window cannot open or the door catch fail to hold.

Protecting Your Home With Trees and Earth

Winter winds, like a forced-air cooling system, can cause substantial heat loss from a house. The loss is due to various effects: lowered air pressure, conduction, and evaporative cooling. These combine to produce a temperature drop called the windchill factor. The chart at right shows how large the factor can be. For example, if during January the average outdoor temperature in your area is 10°F, an average wind speed during the same period of 10 miles per hour will make it seem like–9°F—a net difference of 19 degrees. If your house stands fully unprotected from the wind, the drop of 19 degrees that it is therefore subjected to might be virtually eliminated if you can find a way to block the wind. As an estimate of how much fuel such a step might save, check your fuel bills for January and for a month in which the average outdoor temperature was 19 degrees above January’s temperature. The difference between these costs would be the saving for January. Such savings can range up to 30 percent in a year.

Trees and shrubs can be planted in a variety of ways to redirect the wind. if the cold winds of winter arrive mostly from one direction, a single line of evergreen trees will do a good job of blocking them (Fig. 1); more rows at other angles to the house may be needed if the wind is variable. in the summer, however, these same trees may interfere with cooling breezes. One solution
(Fig. 2) would be to plant a row of deciduous trees (trees that shed their leaves in autumn) to deflect summer winds onto the house. Once autumn arrives and the leaves have fallen
(Fig. 3), the evergreens will function as before to protect the house. Deciduous trees are also valuable as shade trees (Fig. 4) to keep the rays of the hot summer sun off the house. Their advantage over evergreens is that sunlight will be able to get through during the winter to warm the house.
A thoughtful, step-by-step approach to planting windbreaks is advisable. Wind patterns can vary consider ably during the year. in many cases, not until the windbreak is in place can you be sure what its net effect will be. Phone or write your state energy office or local utility company for further information. Local agricultural extension offices can help and may provide you with lists of additional resources.
Various methods exist for keeping wind away from a house. One of the most esthetically pleasing is a strategic placement of trees and shrubbery to block the wind. Planted near the house, trees can also shade it in summer and save on air-conditioning costs. Walls, trellises, and parapets can also be built onto or near the house to deflect air currents. When planning a new structure, consider the shape of the land—slopes and hills strongly affect the way the wind blows.

Underground Houses

Houses that are built into the earth or beneath it are virtually immune to fuel shortages. This is because very little fuel is necessary to keep them heated comfortably above the surrounding temperature of the earth in which they are buried, a temperature that stays remarkably close to 55°F the year round.
This impressive fuel-saving advantage is offset, however, by the desire of most people for open space and sunlight rather than the cavelike atmosphere of an underground dwelling. Moreover, since subsurfacestructures are surrounded by tons of earth, some individuals worry that the walls may collapse or that escape may be difficult in case of fire or other emergency.
Shrubbery windbreaks are most effective when planted no farther from the house than five times the height of the windbreak (150 ft., for example, for a windbreak with 30-ft.-high trees). The trees should be far enough away from foundations and sewer pipes to prevent root damage. The distance can be inferred from tree size; root systems of mature trees usually extend about as far as the trees’ branches.
Structures that impede air flow past the house, such as fences, walls, and parapets, can also serve as windbreaks. Even a trellis—which is normally used to support vines—or a similar wind-spoiling attachment serves this purpose. Traditional Navaho hogan is the basis for the design of this octagonal log-supported home in the southwest. The logs rest on footings of stone and form the roof as well. The structure is covered by a mixture of earth and pumice. A vapor barrier of asphalt paint and stucco protects the logs from moisture.
Many underground houses have been built in this country. Those that have been are often only partly buried. This type of design can still achieve major fuel savings if the layout of the house permits the residents to live aboveground during the warm months of the year and belowground during the cold months. Even if a house is embedded more deeply in the earth, its design can still achieve a degree of airiness by incorporating skylights, sunken courtyards, and aboveground panels that deflect the sun’s rays down light shafts. Another variant is to build the house into the side of a hill. That way one or more walls can be left exposed to let in sunlight and provide views of the countryside.Built into the side of a hill, this Midwest home is nearly impervious to the effects of wind, storms, and tornadoes. An asphalt coating waterproofs the concrete roof and walls, which support more than 1 million lb. of earth. Drainage tiles below footings channel away water that collects there as a result of soil seepage.
There are a number of special problems associated with underground structures. Erosion of the earth that covers the house must be kept in check. Usually this can be done by planting grass or shrubs that stabilize the soil. The shrubs should have short roots so they will not penetrate the walls or ceiling. An underground building must have enough strength to sustain the heavy load of earth pressing down on the dwelling. To achieve extra strength, underground houses are often built in the shape of a circle or octagon, designs that achieve a relatively even distribution of load. Roofs reinforced with steel beams and heavy concrete walls are also used.Extra effort has to be made to keep belowground homes dry. Even with a waterproof vapor barrier around the structure that blocks moisture from the earth, the house must cope with condensation that accumulates inside. Surface houses have enough openings to let interior dampness quickly evaporate. Underground houses, however, need special ducts and blowers to keep them dehumidified. The problem is similar to the one many homeowners experience with their basements; but while a small portable dehumidifier will handle the moisture problem in the average basement, a much larger system is needed to control the humidity in an underground home.