Power Sources, Equipment for Life on a Few Acres by Wesley Gunkel and David Ross
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Power Sources, Equipment for Life on a Few Acres By Wesley Gunkel and David Ross Modern farming and our style of living require the use of energy in much greater quantities than in the past. While re- turning to nature on a few acres may reduce dependence on energy and modern equipment for some, it is hard to escape their use. Power is needed to perform the many tasks found in maintaining and using a few acres. The few acre site may open new energy sources to the owner. Natural energy from wind, water, the sun, wood or coal may be locally utilized. Electricity, natural gas, fuel oil and coal may be supplied by commercial companies. Equipment such as tractors and tractor-operated imple- ments, household appliances, and power tools use many sources. Family living requires surprisingly large quantities of energy. More than 20 percent of all the energy in the United States is consumed in the home. Over half of this energy is used for heating. Both your life style and the nature of any operations on your few acres will determine energy requirements. The loca- tion of your place will determine the most likely energy sources. Most few acre operations will be near electricity or a petroleum fuel source. However, the electrical service may be inadequate for large electrical motors, particularly 3-phase motors. Accessibility for fuel deliveries may be poor during some months, and larger storage facilities may be needed. Electricity obtained from a central station is fairly depend- able and reasonably priced as a rule. Electrical generators on your few acres are ideal for standby operation. If generators are your only source of electricity, some form of energy storage is needed; direct current [d.c] and storage batteries are used. Wesley Qunkei is Professor of Agricultural Engineering, Cornel! University, Ithaca, N.Y. David Ross is Extension Agricultural Engineer, University of Maryland, College Park. 153 Average wattage and amount of energy used per year for selected home appliances Appliance Wattage Annual Energy Equivalent Consumption Gallons of (kw.hrs.) Gasoline Air-Conditioner (room) 1,500 2.000 54.6 Can Opener 150 5 .14 Clock 2 17 .47 Clothes Dryer 4.500 1,000 27.0 Clothes Washer (automatic) 500 100 2.7 Coffeemaker 900 106 3.0 Dishwasher 1,200 340 9.4 Electric Blanket 200 180 5.0 Fan (attic) 350 270 7.4 Food Freezer (15 cu ft) 350 1.200 32.8 Food Mixer 125 10 .3 Food Waste Disposal 500 30 .8 Frying Pan 1,200 240 6.6 Hair Dryer 500 15 .4 Hot Plate (2 burner) 1,250 100 2.7 Iron (hand) 1,000 150 4.1 Lights 1,000 800 22.0 Radio (solid state) 5 20 .6 Range 13,250 1,550 42.3 Refrigerator (frost-free 12 cu ft) 600 1,200 33.0 Sewing Machine 75 10 .3 Television (black & white) 160 400 11.0 Television (color) 350 540 14.8 Toaster 1,200 40 1.1 Vacuum Cleaner 630 45 1.2 Water Heater 4,500 4,500 123.9 Water Pump (shallow) 500 231 6.4 These systems are satisfactory for electric lights but have limited capacity for large power demands. Other sources of commercial energy that may be available at your site are natural or LP gas, gasoline, fuel oil or coal. All of these fuels can be used for both power and heat. Gasoline and diesel fuel are used regularly for tractors. LP gas is nor- mally used for heating, but can be used in cars, trucks and tractors fitted with special LP gas carburetors. In select locations, water and wind energy may be useful for performing some operations. Work on utilization of wind energy has come from many sectors and may result in equip- ment directly coupled to a windmill, or in wind-generated elec- tricity. 154 In 1850, one percent of the total energy consumed in the United States was supplied by wind. Since then more than 6 million small windmills of less than 1 horsepower each have been built. These windmills pumped water, generated electric- ity, and performed other similar tasks. Over 150,000 are still in use. The amount of power available is directly proportional to the cube of the wind velocity, which illustrates the importance of wind velocity. Doubling the wind velocity means 2 x 2 x 2 or eight times the power. As a rule of thumb, continuous winds over 8 miles an hour average are needed to operate a wind- powered electrical generator. Suitable site characteristics include high annual wind speed, no tall obstructions upwind for some distance depending upon the height of the windmill, top of a smooth well-rounded hill, open plain or shoreline, or mountain gap that produces a wind funneling. Consult the windmill manufacturers for spe- cific information. Waterpower is another potential source of natural energy available at a few farm sites. In the past, waterpower provided the energy for grinding flour, sawing wood, and generating electricity. Today waterpower is used primarily for generating electricity in large central hydroelectric plants. Very few of the original small scale systems remain. Interest has developed in harnessing water in rivers and streams for limited supplemental energy. Wood, Solar Energy Wood is a source of energy available at many sites. While* only a small fraction of America's fuel needs are now supplied by wood, it can be used advantageously if a sufficient, low cost supply is available. Fireplaces have been installed in many homes for decorative purposes. Few are used for primary oit supplemelitary heating, as the efficiency is a low 10 percent. Improvements have been made in wood-burning equipment to increase the combustion efficiency of fireplaces and stoves. Wood can be obtained from your own well-maintained woodlot or from forest land nearby. State and local regulations will govern wood collection from public lands where a permit may be needed. Solar energy has been used in recent years to heat and cool buildings, dry agricultural products, power irrigation pumps, generate electricity, heat water, and for other purposes. Solar cells are used to generate electricity from solar energy. Costs of solar cells and associated equipment are expected to come dow^n lATith time. 155 Passive solar systems make use of the building design to capture and store heat. Windows or structural components which absorb heat energy are examples. Passive systems are relatively inexpensive and use few or no moving parts. They are designed into the structure and not added onto it later. Active solar systems use large heat-collecting panels, pumps or fans and storage facilities. The equipment is rela- tively expensive, requires space, and must be maintained. Ex- cept in moderate temperatures, the solar system cannot economically provide all the heating needed. A backup conven- tional heating system will provide 50 to 70 percent. Putting finishing touch on heat collectors (bottom). Solar heat can move directly from collectors into the house or be stored in crushed rock beneath house, as shown in diagram. Working drawings of solar house are available from Extension Agri- cultural Engineers, Cooperative Extension Service at state land grant universities. Ask for Plan 7220, Solar CLJ CxasMSb "^(xx. Kx /fef r ¿TOX^oe [U House. Popular magazines carry articles about build-it-yourself systems and how they perform. A well designed build-it- yourself system will be economically feasible before one pur- chased and installed by a contractor; however, the lay builder must be capable of doing the job. Two rules of thumb on sizing the solar heating system are: 1) the collector area is equal to one-fourth to one-third of the house floor area, depending on the site and geographical loca- tion, and 2) a liquid heat storage system needs 1.5 to 2 gallons of fluid for each square foot of collector, while an air heat storage system needs one-half to three-fourths of a cubic foot of rock per square foot of collector. In addition, the house should be insulated to standards equal to electric heat. Often the many possible conservation practices give sufficient savings in an existing house so that the additional expense of putting in a solar system does not give an economic return. The fastest payoff comes in heating household water. No structural insulation is needed and comparatively small collec- tors—30 to 100 square feet—are used. The storage tank is con- nected to the household hot water heater by a heat exchanger. Fluid in the collector does not mix with the household water, so there is no contamination. Insulating the attic of a house. 157 Field Machinery A wide range of tractors and implements are available from local farm machinery dealers. Most of the larger tractors and implements sold are manufactured in the U.S., while many of the smaller tractors—particularly diesels—are imported. Small compact tractors, frequently called lawn or garden tractors, are also manufactured in the U.S. and are sold by either farm machinery dealers or other specialized stores. Gar- den tractors are designed primarily for light, estate duty and are not intended for continuous heavy service. Consider product reliability, equipment warranty, dealer reputation, and availability of spare parts when you purchase machinery. A successful farm business requires careful management of land, labor and capital. In most cases, machinery costs are high and exceeded only by land costs. Thus it is important to manage machinery properly. This includes planning the use of machinery for timely and productive operation, selecting proper types and sizes, proper care to maintain performance and re- liability, replacing obsolete or wornout machinery at the right time, and deciding if a custom operator should be hired or a machine leased.