FURTHER APPLICATIONS OF ELECTRICITY Ultra Violet present day electric farm is incom plete without its ultra violet ray equipment. Experiments have been made on cattle, pigs and poultry with these rays. It has been found that chickens so treated develop into strong vigorous birds in a much shorter time than under normal conditions. The treat ment is only given during December, January, February and March, for about ten minutes morning and evening. Laying hens have been found to lay better during the winter months when treated with the rays.
Experiments have shown that the danger of rickets in young pigs, owing to their very rapid growth, can be considerably mini mised by treating them with ultra violet rays. This is especially true during the winter. A farmer really has no business to rear young livestock in the winter-time when adequate health-giving sunshine is not available. However, the profits are greater, and the use of ultra violet rays combined with small doses of cod-liver oil, enable him to overcome adverse conditions.
weather conditions constitute one of the greatest risks facing the farmer, for only too often excellent crops are ruined through rain at harvest time. Some years ago the manager of the Sussex farm, as a result of a number of labora tory and field experiments, decided to eliminate this risk, with the result that the hay and corn can now be cut when in the best condition, carted almost immediately, and stacked and cured with the aid of a small fan and an electric motor. This is not a drying but rather a bacteriological process. Stacks of from 15 to i oo tons have been cured without the aid of any pre-heated air. The method of procedure is as follows. On the place where the ricks are to be built, covered channels are prepared, provided with openings at about every ten feet of their length. High sided ex tensions are provided at the openings to give the air a lead into the cavities that are to be formed in the rick above. Over these cavities a drum or former is fixed. These drums are about 3 feet high and 2# feet in diameter. The rick is then built in the ordi nary way. When the crop reaches the level of the top of the drums, the latter are drawn upwards to provide a ventilating shaft. When this shaft has reached about two-thirds of the finished height of the stack, the drum is removed and pieces of trellis are placed over the cavities to prevent f resit material from falling down. The stack is then finished in the ordinary way.
The main ducts in the ground are led to a portable fan which is driven by an electric motor. The time when blowing commences on the stack depends upon the state of the grass. If the grass has been carried in a very wet condition, blowing commences immedi ately and is continued for ten to fifteen hours, thus ensuring the removal of the surface moisture.
The fan is afterwards operated for half an hour every twenty four hours for the ten following days. The object of blowing is to keep the stack within certain temperature limits and thereby control the bacterial action. To this end temperature readings are taken at least twice a day. The thermometers are enclosed in steel cases and pushed into the rick about half way up for a dis tance of about 34 feet. The size of fan used absorbs the full power of a 5 horse power electric motor. While the process was originally designed for curing hay, it has also been used success fully on cereals, thus saving the necessity of stooking and the con sequent loss due to birds and vermin; incidentally also permitting of earlier ploughing.
The whole process is of course dependent upon bacteriological principles, coupled with a knowledge of the art of the ventilating engineer.
In the Garden.—The electric farmer also uses electricity for heating the soil in garden frames, dispensing with the erratic warmth of a horse-manure hot-bed. This is ideal for early spring crops. Excellent water melons have been grown in this way in succession to early lettuces. Around Stockholm where this sys tem has been most extensively employed, 5,000 kilowatts of energy are now used during the nights for this particular application alone. Very intensive illumination of plants in bud quickly brings them into bloom ; seedlings thus treated will not wilt.
Cost of Equipment and Saving Effected.—There is an in crease of about 25 per cent. in the capital expenditure of the electrified farm, but this can be recovered in a comparatively short time, usually about 3 years, whereas, in a factory, io years is the usual time allowed for the recovery of capital sunk in the enterprise.
The saving effected on a medium sized farm, when a few general machines are electrically driven has been carefully compiled, and the table on p. 163 shows how appreciable this is.
Now, 15% interest and depreciation on £76 equals II i 8s. od. Deducting this from the gross saving of 133 12s. 6d. shows a net profit to the electrical installation of 121 4s. 6d., so that, even if there had been no profit, the convenience and other indirect gains would have been well worth while. (R. B. M.) In the United States the utilization of electricity in agriculture has advanced rapidly during the past decade and will surely in crease even more rapidly in the near future. The greatest ob stacle to the electrification of American farms is the great dis tance between them and the consequent cost of installation. The relatively small initial demand for electric power of a few scat tered farms is generally not sufficient to cover the cost of bringing the power to the farms. For the economical generation of elec tricity large plants must be built as near as feasible to the centre of the load of the district which they serve. From the central gen erating plant the power is sent out at high voltage. Where power is to be transmitted long distances it is necessary to employ high voltage in order to reduce the size of wire and hence the cost of the transmission line. Should low voltages be employed, the size of wire required to carry the power with a reasonable loss would become so great that the cost would be prohibitive.
Cost of Electrification.—It has been found that the cost of serving the average farm with electricity is about five times the average cost of serving the average city customer. It is, therefore, necessary for the farmer to use about five times the quantity of electricity as used by the city customer in order for the cost per unit of electricity, kilowatt hour, to be the same. The problem of farm electrification, in its broadest sense, is one of finding uses for electricity on the farm which will insure the utilization of sufficient power to justify the service at a price the farmer can pay and the power company is willing to accept. To this end the National Committee on the Relation of Electricity to Agriculture was formed. This committee is composed of the following organ izations: American Farm Bureau Federation; American Home Economics Association; American Society of Agricultural Engi neers; General Federation of Women's Clubs; Individual Plant Manufacturers; National Association of Farm Equipment Manu facturers; National Electric Light Association ; National Grange; National Electrical Manufacturers' Association; U.S. Department of Agriculture; U.S. Department of Commerce; U.S. Depart ment of the Interior.
In 1928 associations in 24 States were studying the same prob lems, largely through the agricultural colleges and experiment sta tions. Their investigations have shown that many farms can find practical and economical use for the amount of electricity pro vided at the minimum charge. Some 200 separate and distinct uses of electricity on the farm are now listed. Many of these uses necessitated the design and development of special apparatus and devices, and as the service for the farm differs materially from other classes of the electric light and power business, it became necessary to draft special rates and regulations.
The price of electricity depends upon the relation between the expense of carrying the power to the point of use and the amount of power supplied. The rate forms generally provide for the financing of the line construction by the power company, thus making the farmer's capital available for the purchase of electrical equipment. While many forms of rural rates are in use through out the country, there appears to be a general tendency towards standardization in two general types: (I) Monthly service charge plus a relatively low energy rate, usually in two steps. (2) a guaranteed minimum yearly revenue with various energy rates. A survey by the rural electric service committee shows that on Jan..i, 1927, there were 227,442 farms in 27 States having service from high tension lines, which is an increase of 86% for the same 27 States over Jan. 1, 1924. On this basis, between 300,00o and 350,000 farms were receiving electric service on Jan. 1, 1927, and it is believed that the number of farms having their own electric plants is as great. This gives between 600,000 and 700,000 farms in the United States using electric power, or about 1o% of the total number.
The electrically-operated household refrigerator (see REFRIGER ATORS, HOUSEHOLD) is rapidly being installed in the farm home. The need of refrigeration on the farm is generally greater than in the city, as larger quantities of perishable foods must be kept for longer periods. The electric range is a most convenient method of cooking food, but its intelligent operation is one of the most important factors. If meals are planned so as to use for the most part the insulated oven and boiler, the energy consumption can be greatly reduced below that required where the open grids are used. For satisfactory cooking with electricity, using automatic control, it is essential that the voltage applied be that for which the heating elements are designed, as the temperature of the elements drops rapidly with a decrease in voltage.
An electric water heater should be used in conjunction with an electric range. The heater should not be larger than is absolutely necessary to provide the quantity of hot water needed, as losses by radiation are considerable. A well-insulated heater of about 3 gal. capacity hand operated, is usually employed for providing hot water in the kitchen, principally for dish washing. Electricity also finds large use On the farm in connection with radio. In April 1927, the number of radio sets on farms was 1,251,186. This number is about 25% of the total number of farms in the country. In Sept. 1928 it was estimated that the total number of sets on farms was I,5oo,000, or about 3o% of the total number of farms. The number of farms reporting telephones in 192o was The number in 1928 was perhaps 3,000,000, or about 5o% of the entire number of farms in the country.
Dairying.—Many dairy farms have electric service. Electric lights are particularly useful in the dairy barns and milk house in order to provide illumination for the early morning and evening milkings and for feeding the cows, cleaning buildings, etc. The silo should be properly lighted not only for convenience and free dom of movement, but for safety as well. Electricity is largely responsible for the rapid development of the milking machine. The electric motor, owing to its light weight, simplicity of construction, cleanliness and constant speed, furnishes an ideal drive for the milking machine. Two types of these machines are in use, the pipe line machine and the portable machine. The pipe line ma chine, as the name implies, consists of a number of pipes installed in the barn with a vacuum pump located in a separate room. The portable type has the motor and vacuum pump mounted directly on the cover of the milk receptacle. This gives a direct suction to the machine and eliminates considerable leakage which occurs in the pipe line. The portable machine is usually arranged as a double milking unit ; that is, one machine will serve two cows. The capacity of the electric motors for these double units is standard ized at 6 horsepower. The power required to operate the pipe line type varies with the type and efficiency of the particular machine and usually ranges from $ to a horsepower per cow milked at one time. The time saved by the milking machine over hand milking is considerable. Tests show that with a herd of 15 cows, the saving in time amounts to 371 minutes at each milking, or an hour and a quarter a day. The time saving per cow increases with the size of the herd. There are two serious problems encountered in the operation of milking machines : viz., low voltage and sani tation. Low voltage produces unsatisfactory operating conditions, but can be remedied by proper electrical installations.
The refrigeration of milk embodies two distinct problems; viz., the initial cooling for removing the animal heat, and the storage at a temperature sufficiently low to greatly retard the growth of bacteria. The initial cooling is accomplished by running the warm milk over some form of surface cooler, while refrigerated water or brine is pumped through the interior of the cooler. Usually the cooler coils are divided into two sections. Cool well or spring water is pumped through the upper section and refrigerated brine through the lower section. Such an arrangement economizes in mechanically produced refrigeration, as approximately half the cooling is accomplished through the use of the cold well or spring water. The morning's milk is generally cooled to about 45° F, placed in insulated cans and taken immediately to the milk plant or railway station. The night's milk comes from the surface cooler at about 5o° or 55° F, and is placed in cans and stored overnight, either in an insulated tank of refrigerated water or in an insulated cold storage room, where the temperature of the milk is further lowered throughout the night to around F. Refrigeration is stored in the tank of water and also in the tank of brine which is located in the top of the cold storage room. Storing up refrig eration makes possible the use of a much smaller refrigerat ing plant, as the plant can be operated a longer time, thus storing up refrigeration which is available for quick action when needed. The pasteurizing of milk by electricity is little employed. The usual method is to pass the milk between electrodes, the milk itself forming a part of the electric circuit. The resistance to the flow of electricity offered by the stream of milk serves to heat the milk to a temperature sufficiently high to destroy the bacteria. Alter nating current is employed, generally at a voltage of 220. The regenerative or heat exchange method is used to reduce the quan tity of electric energy required to a minimum.
Owing to the large amount of hot water required in the dairy for washing purposes, it is impracticable to employ electric energy as the heating medium except when a very low rate per kilowatt hour is available. Many States require the sterilization of utensils employed in dairying, and electricity is being used to a consider able extent for this purpose. The type of sterilizer generally employed consists of a well insulated box containing the heating elements. The heating elements are placed at the bottom of the box and covered with a small quantity of water, while the utensils to be sterilized are placed on a false bottom just above the heating elements. The temperature is automatically held at about F. It should be noted that the operation of the cream separator at exactly the proper speed is very important for efficient separation. The practically constant speed of the electric motor, especially of the alternating current type, makes it an ideal drive for this class of work. Consequently, on the dairy farm where electricity is available, the cream separator is one of the first pieces of equip ment to be electrically equipped. The average size of farm sepa rator is provided with a motor ranging in capacity from * to horsepower. The * h.p. machine will handle up to i,000 lb. per hour, while the 4 h.p. will handle up to 1,40o pounds.
The heating of the drinking water for the dairy cow, and con stant maintenance of a supply at the proper temperature, has served to increase the yearly average of milk production from 5 to 15%, the increase being greater in colder climates than in warmer. The milk tester is a valuable piece of apparatus for the dairy as it enables the dairyman to make more accurate selections in the building up of his herd on a butter fat basis. The energy consumption when operated electrically is very small and the speed of rotation is practically constant.
Bottle washers for the average dairy require about A h.p. motor and operate at about 1,800 r.p.m. They are convenient and eco nomical in the use of electric energy. The animal groomer is largely employed. It thoroughly removes the loose hair and dirt from the udder and flanks of the cow without permitting them to escape into the stable air and eventually into the milk. The con trol of flies by means of the electric fan is also largely employed. The usual method is to install vertical ceiling fans just inside the doors, the draft from the fans preventing the flies from entering. Electrocution screens have been used with some success in de stroying flies and other insects around the dairy. Some trouble, however, has been experienced due to the short-circuiting of the wires by the dead flies.
Ensilage is one of the best feeds for dairy cattle, and practically all dairy farms are equipped for providing this food. Due largely to the different methods of operating the ensilage cutter, the energy consumption per ton of material ensiled is extremely variable. The size of machine, sharpeners of knives, speed of fan, length of cut, method of feeding machine and kind of material being ensiled all affect the energy consumption per ton. Dull knives will increase the energy consumption approximately 5o%. The speed of the fan should be just sufficient to elevate the mate rial into the silo. The motor load fluctuates over a wide range, depending upon the care and uniformity of feeding the cutting machine. Owing to this wide fluctuation of load it is very im portant that the wires connecting the motor to the transformer be exceptionally large, especially if the motor is at a considerable distance from the transformer. In other words, the wiring should be so proportioned that there will be not over to% drop in voltage at the motor terminals under extreme conditions.
Owing to the short time required for cutting ensilage for a single farm, and to the comparatively large size of motor necessary for driving the machine, a community-owned outfit is sometimes employed. The outfit, in addition to the motor and ensilage machine, consists of a portable substation embodying the necessary transformers. This substation is mounted on a truck and trans ported from farm to farm to handle the ensilage cutting, thresh ing, etc. The portable substation eliminates the necessity of a bank of large transformers to supply the power for these jobs which are performed for only a short period of each year, and in this way lowers the cost of transformer installation for each of the individual subscribers. Such an outfit will provide ample power for any of the heavier farm operations where rotating machinery is used.
The average working day for the hens is from 12 to I 3 hours from November to March. In the case of late maturing pullets it has often proved practicable to use the lights even earlier. To avoid sudden changes in the habits of the flock, the artificial day should be lengthened gradually in autumn and reduced gradually in the spring. The usual practice is to light from 5 A.M. until day light and from dusk until 7.30 or 8.00 P.M. There is need for gentle brightening and dimming of the lights. If these are turned off suddenly and the flock is plunged into darkness they become demoralized and many roost on the floor. An arrangement is provided that will extinguish the lights gradually, to simulate the effect of the natural approach of twilight. A satisfactory method of doing this is to dim the lights down to at least half voltage for a period of from io to 15 minutes before turning them off entirely. When the lamps are dimmed, the hens instinc tively go to roost in their accustomed manner.
The lights for the poultry house are placed about 6 ft. from the floor and io ft. apart. They should be fitted with cone-shaped reflectors 16 in. in diameter and 4 in. deep. The reflecting surface should be covered with three coats of aluminium bronze paint. With the above mentioned spacing 4o-watt lamps will properly light 200 sq.ft. of floor space; therefore, to find the number of lights required, divide the square feet of floor space by 200. The nearest whole number will be the number of lighting units required. Should the poultry house be divided into pens, figure each pen separately. The energy consumption for lighting is from 3 to 5 kw. hours per month for each ioo hens. Warming the drinking water for poultry is necessary for maximum egg production. When the temperature is belpw freezing, hens consume about 2 5 % more warm water than cold, and about 5% more when the temperature is above freezing. The result of drinking more water is better appetites and more eggs. Electrically operated dropping boards are employed to some extent, and have practically eliminated the manual labour required for cleaning the boards.
Electricity is the ideal heating medium for the incubation of eggs, because of the reliability and ease of automatic temperature control. Automatic thermostats are the heart of the incubator, consequently they should be sensitive, reliable, durable and main tain their setting. They should be capable of controlling the temperature inside the incubator to within plus or minus 2° F from the thermostat setting. The incubator should be well in sulated in order to conserve heat, thus making it possible to control the temperature more accurately and to maintain the temperature for a long period in case the power should be cut off. It is the usual practice in designing incubators to provide in the heating element watt per egg.
Chilling and over-heating are to be guarded against in the brooder. Electricity furnishes the most reliable source of heat for this purpose. The brooder should be equipped with a no voltage or temperature alarm to notify the poultryman when the power fails so that he can take the necessary steps to keep the chicks warm, such as placing a blanket over the brooder. A tem perature alarm is further valuable in that it gives warning when the thermostat points fail to function. The temperature regulator need not be so sensitive as in the case of the incubator, as a temperature range between plus or minus 3° F from the thermostat setting is satisfactory. The area per chick under the brooder is one of the important factors in determining the energy consump tion. The construction of the brooder and the temperature of the brooder house are other factors affecting the quantity of heat required. The area per chick allowed under the brooder varies from 3 z to 72 sq.in. and an energy consumption of from t to 3 watts per chick. The maximum of 3 watts is required when the outside temperature is around o° F.
The electric brooder, due to the even and dependable heat, has proved successful in the raising of turkeys. During cold damp weather the mortality rate among newly hatched birds is usually very high. This has largely been overcome by the employment of the electric brooder. Time and labour are saved the poultry man by the employment of electrically driven green feed cutters and bone grinders, which operate with a small energy consump tion. The electrically heated oat sprouter provides an easy and satisfactory means of providing green feed requirements. A large, well insulated sprouter, when placed in a warm protected location, uses about 75 kw. hours per month for sufficient oats for t,000 birds. A smaller type sprouter consumes about 15 kw. hours per month to furnish green feed for about 200 birds.
Extensive experiments have been conducted on the treatment of poultry with ultra-violet rays. The lack of vitamin D in the ration of growing chicks which are confined indoors, causes leg weakness or rickets. Vitamin D controls the utilization of minerals in the ration, and the use of this vitamin is greatly increased through the application of ultra-violet rays. These rays are present in sunlight, and poultry that are exposed to sunlight for the greater part of the day do not require treatment with arti ficially produced ultra-violet rays. Ordinary window glass, which is commonly used in the front of poultry houses, prevents the passage of these rays in sunlight, and it therefore becomes neces sary to supply them artificially. The energy consumption of the ultra-violet lamp is small. About 7 2 kw. hours is required per month per i,000 chicks treated, one month of treatment generally being sufficient. In the case of hens about ioo kw. hours are required per month for each t,000 birds treated. The ultra-violet lamp offers the poultryman a convenient method of maintaining the vigour of his flock or the vitamin content of the eggs during cold sunless days of winter when the birds must be kept in the house.