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Energy Efficiency in Indian Agriculture
Approaches to efficient use of water in agriculture that could result in considerable savings in energy.
The agriculture sector in India uses 85% of the country's available fresh water. However, irrigation efficiency is only 20-50%. In other words, Indian agriculture wastes up to half of the country's fresh water supply. Although from a basin perspective, much of the wasted water is reused, significant amount of water is wasted primarily due to irrigation inefficiencies.
There are inefficiencies on the energy front as well. Agriculture accounts for about 27% of the total electricity consumption in India. The consumption is somewhat higher in the states like Andhra Pradesh, Gujarat, Madhya Pradesh, Uttar Pradesh, Karnataka, and Haryana, where agricultural electricity use is between 35-45%. However, sale of this electricity amounts to no more than 5-10% of the state electricity boards' revenues.
Flat Wastage
The adoption of flat rate pricing for agricultural power is cause for this perverse state of affairs. Under this system, a farmer pays a fixed price per horsepower per month for electricity. Therefore the marginal cost of pumping water is zero. This leads to energy wastage, over-pumping and inefficient selection of crops. Flat rate pumping also masks the true cost of power to farmers.
The tariff structure and the poor combination of technology and management are responsible for water loss, unsustainable exploitation of groundwater and the high energy losses associated with the distribution and end-use of electricity in irrigation water pumping.
Significant energy losses are associated with the distribution of electricity and in the poor selection, installation, maintenance and operation of the electrical motor pump system. A vicious cycle operates two sub-systems in tandem: the electrical distribution system and the water pumping system. This vicious cycle comprises three sub-cycles: The technology sub-cycle, the financial sub-cycle and the socioeconomic sub-cycle.
Financial Sub-Cycle
Poor quality of power and the resultant impact on performance and efficiency of pump results in low crop yields and incomes. Under these conditions, electricity tariff revisions for farmers are politically resisted and payments on electricity bills are postponed, resulting in low cost recovery.
Low cost recovery, in turn, is linked to under funding of operations and maintenance of the power delivery systems. This coupled with poor engineering standards and state of the LT distribution systems and inappropriate structure, policies and staff skills of many State Electricity Boards (SEBs) closes the circle by providing poor quality of supply service.
This sets off a chain reaction of events of motor burnout and transformer overloading. These further depress cost-recovery levels and the vicious cycle sets in. Sub-optimal allocation of resources towards the distribution system places further burden on the already vulnerable system causing deterioration in the quality and reliability of supply.
Causes of Water Loss
There are five causes of water loss.
First is the choice of crop. Farmers select crops that bring in maximum benefit to them and not crops that use less water. The natural environment also plays an important role in determining how much water is lost. Soil types, climate and hydrology all affect water losses.
India has a very diverse natural environment. A recent classification by the National Bureau of Soil Survey and Land Use Planning distinguishes 20 broad agro-ecological zones, separated by natural features and crop growing periods. Each of these agro-ecological zones comprises many myriad microhabitats. Therefore, there are always some regions in India that will have lower water use efficiency than others and any water-efficiency project must be site-specific.
Technology is next on the list of causes. The type of irrigation and delivery systems determines how efficiently water is used. Drip and sprinkler irrigation systems are more complex in design but can be more easily operated with low losses than surface irrigation methods, which require a high degree of flexibility in water supply. Pipe delivery systems generally lose less water than the more commonly used canal systems although canal systems are often more easily maintained.
The type of control structure used in irrigation is also important. Fixed control structures are less flexible but require a lower degree of expertise to operate and maintain. All this lends to the fact that technology that requires less skill to manage may often incur less water loss than systems that are theoretically more efficient. Again, site specific analysis is essential in determining the proper technology to be used.
The fourth cause of water loss is farmers. Farmer characteristics such as skills, knowledge, organization and motivation determine their ability to manage water.
The fifth cause of water loss is the central water agency and its policy. This cause should be recognized as the most important cause because it underlies the others.
The efficiency of any water management technology is dependent on the reliability of the water supply. Farmers cannot function effectively without a reliable supply of water and have no incentive to use water efficiently if it is supplied with little or no charge.
To provide the farmers with the means and incentive to conserve water, municipalities must provide water at a realistic cost and simultaneously improve the quality of the service they provide to the point where farmers will be willing to pay for it.
In India water is supplied to the agricultural sector virtually free of charge and therefore farmers use as much of it as possible. Unfortunately, municipalities raising the price of water cannot solve this problem. Farmers also must be willing to pay for the water. It has been shown that farmers in India are willing to pay for the water they receive provided that the supply is reliable.
Currently water supply to farmers is very unreliable. Farmers never know how much water they will get and when it will come. As a result of this and the low or non-existent cost, valves are most always open so that farmers can get the most out of the syncopated water flow.
These irrigation costs accounts for as much as 20 percent of the net value of output from these crops. Farmers are willing to pay for timely and reliable water supplies for irrigation. Hence, those institutional and financing arrangements that ensure reliable water supplies are likely to be more sustainable for improving water use efficiency than those that concentrate only on cost-recovery.
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