The world is lightened to an extent of 38.3 % by burning of
coal, wood and vegetation, 19 % through hydro (water), 17.5 % through nuclear
energy, 14.9 % by gas, 9.9 % by oil and 0.4 % by others (wind, landfill gas and
solar) means. The energy generated through such means is used to run industries,
use in household affairs and agricultural productivity. Similarly, per capita
consumption of electricity in different human requirements and in different
countries of the world are as (kilo watt hours): USA (11,753), Japan (6,176),
Singapore (4,889), Malaysia (1,146), Iran (724), Thailand (636), China (448),
Pakistan (340) and India (292). There are nearly 2.5 billion people in the world
without access to electricity, so there is an urgent need for a strategy, of
renewable energy source usage for the benefit of mankind.
Energy use in food production has been increasing faster than
many other sectors of the world economy. The major question is how to stop
uncontrolled human population growth. Man must solve the ultimate problem of
increasing population numbers. We must find genuine ways to increase food
production on the world's limited arable land resources through the efficient
use of fossil energy. Suggestions have been made that the world's potential
arable land might be doubled with irrigation and the significant alterations of
parts of the ecosystem. Only about 12% of the world's cultivated land is now
irrigated. Unfortunately, irrigation and other environmental manipulations
require enormous amounts of energy. For example, a litre of water weighs 1 kg
and about 12.2 million litres (12,200 metric tons) of water are needed to
produce 5000 kg of corn/ha in the subtropics. To produce the high protein
calorie diet consumed by the average American, about 160 million hectares are
utilized for crop production in the U. S.
The world demand for food is expanding more rapidly than ever
before in history. Increase in population and changes in its spatial
distribution have aggravated the food situation during the last 35 years.
Besides population growth, rising affluence, agricultural inefficiency and
misguided political expediency have contributed to the further aggravation of
the problems. Rising affluence is rapidly emerging as a major new claimant on
the global food resources. Currently, the agricultural resources necessary to
support one inhabitant of a more affluent country can support on an average five
citizens of developing countries such as Bangladesh, Uganda or Colombia and many
more. Shortages and higher prices for fuels have resulted in increasing prices
and shortages of crop production inputs such as fertilizers and pesticides.
Recently, fertilizer prices increased from 3-2 fold in various parts of the
world. Pesticide prices increased from 2-5 fold and again in some areas none was
available. Shortages of these and other agricultural inputs that depend on
fossil fuel for their production have had a significant impact upon agricultural
production in all parts of the world. The present years are crucial for mankind.
Population numbers are currently over 6 billion and 16 billion by the year 2135.
Food shortages in the world already exist, at least half of the world's
population is suffering from protein calorie malnutrition. The standard of
livings can generally be achieved by way of sustained economic growth over a
number of years. Growth development of agriculture and industry requires energy.
The per capita consumption of energy in Pakistan is very low
in the world. In any development plan of our country the growing demand of
energy assumes great importance. For development of economical growth, the major
effect in the next decade world have to be through an increase in the production
of coal and a search for new reserves of oil. Our oil reserves are limited. Our
dependence on imported oil is on the rise every year. We have several large
reserves of coal, but our coal has high ash content. Coal used for power
generation in the country has ash content of about 48 %.
In the production of food for mankind, relatively a few crops
are utilized. The estimate is that of fifteen crops provide nearly 90% of the
world's food for man. These crops include rice, wheat, maize, sorghum, millet,
rye, barley, cassava, sweet potato, potato, coconut, banana, common bean,
soybean and peanut. These fifteen crops also occupy about 3/4 of the total field
land of the world. With the current and future shortage of energy resources,
alternatives techniques will be required to make more effective use of energy
resources in agricultural production as well as its other utilization for human
benefit. Some of the practical alternatives which might be employed in crop
production may be as: Labour: (Labour is the source that is in abundant supply
and becomes more abundant in less developed countries as the world population
continues to increase. Therefore, every effort should be made to make crop
production labour intensive within the viable economic constraints. To increase
the labour inputs requires careful consideration of both the economic and social
aspects of the problem.
Fertilizers account for almost half of the energy used in
agriculture. The single largest input in the US and also in many other countries
are fertilizer (N. P and K). Compared with phosphorus and potassium, the use of
nitrogen requires the largest quantity of energy in crop production. Thus as
energy supplies decrease other potential fertilizer sources such as livestock,
manure, some agricultural wastes and other organic wastes can be utilized.
Thus, when fertilizer is applied to during one year by either
3 cows, 22 hogs, or 207 chickens. Besides, adding nutrients to the soil, manure
adds organic matter, which increases an average hectare of corn at a rate of 125
kg nitrogen, 35 kg phosphorus and 67 kg of potassium; the same and of nitrogen
is available from manure produced the number of beneficial bacteria and fungi in
soil, makes ploughing easier, improves the water holding and percolation
capacity of soil, reduces soil erosion, and improves the ratio of carbon to
nitrogen in the soil. These same advantages, results from the use of crop and
other organic wastes. Tractor is an important input in the agricultural work.
Although, it reduces the work of at least 13 labourers, but its work in the
field minimize the time consuming factor required for preparation of a field.
But, tractor needs energy which is generated by the application of gasoline or
diesel. About 9.4 litres of gasoline are used for tractor application per
hectare. Pesticides/insecticides are also important input in the control of
insect/pest swarm in the agricultural fields. Their application to the crop is
only possible through the use of energy in form of petrol. Thus energy has great
link in the operational work for the improvement of soil fertility.
Conclusion: To maintain the supply of energy to keep the food
system going, hopefully new energy sources will be developed. The energy used in
crop production can be divided into two categories: (i) energy used to increase
yields (fertilizers, hybrid seeds, etc); (ii) energy used to reduce inputs
(machinery, gasoline, etc). Food production in the less developed countries will
have to depend primarily upon energy inputs to increase yields and less upon
heavy machinery. A surplus of labour already exists in many parts of the world.
The problem of population control must be reemphasized. The
human population cannot continue to increase without a continual decline in
living conditions and worse misery than the majority of the world population
faces today. The world urgently needs population control in each and every
nation. Our efforts in agriculture are forward increasing food supplies and
"buying time" to implement population controls.