The energy source that India, like most of the world, has a surplus of its needs and inexhaustible “reserve” is the sun. The energy that comes from the land of sunshine each year exceeds the total energy that has been and will be produced by the humanity of all nonrenewable resources (including nuclear). Even for a relatively small territory, such as India, the amount of sunlight incident is estimated at five quadrillion watts per year. If even one hundredth of that could be used, is superior to all current and projected the country’s annual energy, population growth and increasing per capita consumption though. Why then are lagging in efforts to make full use of this resource?
First, with the sunlight, as with any other source of energy, it has to be available in a useful way in time and place. With sunlight is sometimes the case, but most cases you need to convert to other ways to meet human needs. These include lighting, space to keep the heat hot water heating or purification, or industrial applications cooking, ventilation, air conditioning and refrigeration, electricity generation, etc.
In India, at an average of 200-250 watts of sunlight received per square meter of surface, which is typical of the tropical land and sub-tropical regions, and considerably higher than the temperate zone. This makes large scale both centralized and decentralized (non-network) applications attractive. Unfortunately, the unit costs for solar power generation ranging from 2.5 to 15 times higher than conventional sources. R & D efforts around the world have been reducing costs, but it could be decades before non-solar energy becomes a competition. While India ranks sixth worldwide in terms of investment in renewable energy, most of this has been less in the wind and solar field.
The state of Rajasthan is perhaps the one that best suits the large-scale solar power generation because of its large proportion of days without clouds and substantial wilderness area of land available. With this in mind, the state government has allocated 35,000 square kilometers for solar power generation. There are plans to integrate solar energy 140 MW plant to be set up near Jodhpur. This is not pure solar energy, but a combination of heat recovery from a natural gas turbine with a parabolic solar collector system that provides up to 40 MW. The total cost is estimated at Rs.871. The proposals for 50 MW of solar in the desert are still to materialize. While Rajasthan has many advantages with respect to solar energy, it also has security problems, as it is located near a sensitive international border, bringing the vulnerability of large-scale installations of any kind of concern.
One area in which solar energy can have a major impact is the power supply in rural areas. To date, only about 55 percent of households have been electrified. The rest are mostly in mountainous areas or other places where electrification based network is difficult, expensive and risky. Decentralized energy sources are the best bet for energy supply to these areas, and numerous government agencies, businesses, and NGOs are carrying out the developing world.
These applications include passive solar architecture, such as the Trombe wall, used for heating in cold areas like Ladakh, solar cookers, dryers, water heaters, stills, and geothermal heat pumps (primarily for air conditioning).
Photovoltaic panels are used for street lighting, signals, telecommunications, interior lighting, and other domestic purposes in areas outside the network, and solar pumps for irrigation.
The community includeS applications of solar cooking in the kitchen Auroville, which serves about 700 people daily. One type of system used in large reflector in the kitchen is the system of Scheffler. The largest of its kind in the world was built in Abu Road, Rajasthan, with a capacity of 35,000 meals a day.
Thus, there have been numerous efforts to harness solar energy in various parts of India in recent decades, but the country has a long way to go in making full use of this valuable resource which means energy security, sustainability and reducing emissions of carbon dioxide emissions and other adverse environmental impacts. The solar detailed map of India indicates the amount of sunlight available in every part of the country. This untapped potential presents both a challenge and a huge business opportunity for venture capitalists, social entrepreneurs, technologists and green.