Solar power

India is both densely populated and has high solar insolation, providing an ideal combination for solar power in India. Much of the country does not have an electric grid, so one of the first applications of solar power has been for water pumping, to begin replacing India's four to five million diesel powered water pumps, each consuming about 3.5 kilowatts, and off-grid lighting. Some large projects have been proposed, and a 35,000 km² area of the Thar Desert has been set aside for solar power projects, sufficient to generate 700 to 2,100 giga watts.
With about 301 clear sunny days in a year, India's theoretical solar power reception, just on its land area, is about 5 Ph/year (i.e. = 5000 trillion kWh/yr ~ 600 TW). The daily average solar energy incident over India varies from 4 to 7 kWh/m2 with about 2,300–3,200 sunshine hours per year, depending upon location. This is far more than current total energy consumption. For example, even assuming 10% conversion efficiency for PV modules, it will still be thousand times greater than the likely electricity demand in India by the year 2015.
Solar power is currently prohibitive due to high initial costs of deployment. To spawn a thriving solar market, the technology needs to be competitively cheaper — i.e. attaining cost parity with fossil or nuclear energy. India is heavily dependent on coal and foreign oil — a phenomenon likely to continue until non-fossil / renewable energy technology become economically viable in the country. The cost of production ranges from Rs 15 to Rs 30 per unit compared to around Rs 2 to Rs 6 per unit for conventional thermal energy.