Solar is an important, although currently underutilized, energy resource in India with the potential to offer an improved power supply (especially in remote areas) and increase the security of India’s energy supply. On average, the country has 300 sunny days per year and receives an average hourly radiation of 200 MW/km
The India Energy Portal estimates that around 12.5% of India’s land mass, or 413,000 km2, could be used for harnessing solar energy.This area could be further increased by the use of building-integrated PV. Though large-scale CSP has not yet been deployed in India, one study has estimated that this technology alone could generate 11,000 TWh per year for India. In addition to India’s potential for widespread deployment of solar technologies to supply electricity across the country, India also has the potential to significantly reduce electricity demand through increased deployment of solar water heaters (SWH), which can be deployed on rooftops in the built environment. Although India already has a strong solar cell production industry, until now, there has not been a high demand for them in the domestic market. In response to the announcement of JNNSM in November 2009, substantial expansion in the domestic solar market is anticipated. JNNSM’s target of achieving at least 20,000 MWof grid-connected solar power by 2022 could make India one of the leading solar countries in the world, not only in total installed solar capacity but also in manufacturing components and technology research and development. The target encourages development of both PV and CSP technologies by allocating 10,000 MW of the goal to each technology. According to JNNSM, a further 2,000 MW of off-grid solar power capacity are to be installed by 2022. In order to achieve the goals, MNRE seeks to create an attractive environment for investors, including incentives such as feed-in tariffs.
Estimates of global horizontal irradiance (GHI) for India are available from several different organizations. The U.S. National Aeronautics and Space Administration (NASA) Surface Meteorology and Solar Energy (SSE) dataset provides estimates of GHI at a 1° spatial resolution, which is approximately 100 km at 26° N latitude and can be visualized and downloaded from the Solar and Wind Energy Resource Assessment (SWERA) Web site.
Solar resource maps at 40-km spatial resolution developed using the National Renewable Energy Laboratory (NREL) Climatological Solar Radiation model are also available from SWERA. NREL has recently released 10-km resolution solar resource maps for India based on the SUNY satellite to irradiance model. The annual average GHI across India, which illustrates that most areas of the country have greater than 5.5 kWh/m2/day of GHI, and the amount reaching a collector could be augmented by optimizing its orientation.