Sources of Farm Power
Various types of agricultural operations on a farm can be broadly classified
- Tractive work such as seed bed preparation, cultivation, harvesting and
- Stationary work like silage cutting, feed grinding, threshing, winnowing
and lifting of irrigation water. These operations are done by different
sources of power, namely human, animal, oil, tractor, electricity and wind.
Human power is the main source of power for operating small tools and
implements. They are also employed for doing stationary work like threshing,
winnowing, chaff cutting and lifting irrigation water. On an average a man
develops nearly 0.1 horse power (hp).
The most important source of power on the farm all over the world is animal.
It is estimated that nearly 80% of the total draft power used in agriculture
throughout the world is still provided by animals. Animals like bullocks and
buffaloes happen to the principle sources of animal power. Camels, horses,
donkeys, mules and elephants are also used in farm work. The average force a
bullock can exert is nearly equal to one tenth of its body weight. A medium
size bullock can develop between 0.50 to 0.75 hp.
The third important source of farm power is mechanical
power that is available through tractors and oil engines. The oil engine
is a highly efficient device for converting fuel into useful work. The
efficiency of diesel engine varies between 32 to 38 per cent. Diesel
engines of larger size are used on tractors.
Electrical power has become a very important source of
power on farms. The largest use of electric power in the rural areas is
for irrigation and domestic water supply. Use of electricity in dairy
industry, cold storage, fruit processing and cattle feed grinding has
The availability of wind power for farm work is quote
limited. Where the wind velocity is more than 32 km/hr, wind mills can be
used for lifting water. A wind mill having 3.6 m diameter wheel mounted on
12.0 m tower is able to produce from 0.1 to 0.9 hp with the wind velocity
varying from 6.4 to 37 kmph. Thus the average capacity of a wind mill
would be above 0.5 hp.