“I’d put my money on the sun and solar energy. What a source of power! I hope we don’t have to wait until oil and coal run out before we tackle that.”- Thomas Edison
India is a country with abundant natural resources, and solar power is not left behind. In a recent document published by the Ministry of New and Renewable Energy (MNRE), it has been established that India today receives more than 5,000 trillion kWh/year of solar radiation, which is far more than its total annual energy requirement. The radiation can have various usages in thermal and voltaic application areas.
Solar thermal technology uses the sun’s energy, rather than fossil fuels, to generate low-cost environment-friendly thermal energy. This energy is used to heat water or other fluids for industrial, commercial and domestic sectors of the country. In addition, it can power solar cooling systems. In new-age civil construction setups, solar-powered steam-generating systems and air-heating technologies are in vogue, especially in urban landscapes.
Solar photovoltaic technologies have their own application areas and these are used majorly for solar lanterns, solar home systems, solar streetlights, solar pumps, solar power packs, rooftop SPV systems, etc, reducing the burden on conventional fuels. So what’s the future ahead?
Wider acceptance of solar thermal systems drives business value in the long run by providing the following set of benefits:
- Reduced bills: Large business houses that require many gallons of hot water and other fluids must pay higher amounts for fuel-heating requirements, whereas manufacturing units using solar power save nearly 70 per cent on this cost.
- Benefits of compliance with government mandates: Many areas and green zones must meet some government mandates and solar thermal systems help meet the requirements set. This also benefits them in terms of sops from the government while also giving a ROI.
- Reduction in carbon footprint: By utilising solar energy instead of fossil fuels, solar thermal systems reduce the amount of onsite-generated, carbon-based greenhouse gases that businesses emit into the atmosphere.
Early 2010, the government of India, realising the benefits of solar power, launched the National Solar Mission with an initial target of deploying 20,000MW of grid-connected solar power by 2022. The idea was to reduce the cost of solar power generation through the following measures:
- Long-term policy framework to support the initiative
- Large-scale deployment goals
- High-resource R&D
- Domestic production of critical raw materials, components and products
After nearly five years of this initiative, with the mission taking off well the target has been revised to 100,000MW solar power generation capacity with the salient features remaining the same.
The way forward
With the threat of climate change, solar is the technology to rely upon in addition to the other forms of renewable energy. Solar electricity generation is one of very few low-carbon energy technologies with the potential to grow to very large scale. Recent years have seen rapid growth in installed solar generation capacity, great improvements in technology, price and performance, and development of creative business models that have spurred investment in residential solar systems.
Nonetheless, further advances are needed to enable a dramatic increase in solar contribution at socially acceptable costs. Achieving this role for solar energy will ultimately require that solar technologies become cost-competitive with fossil generation, which are appropriately penalised for carbon dioxide (CO2) emissions with substantially reduced subsidies.
Photovoltaic modules (PVMs). The cost of installed PVM is historically driven by: the cost of the solar module and the balance-of-system (BOS) costs, which include costs of inverters, racking and installation hardware, design and installation labour, and marketing, as well as various regulatory and financing costs. After years of development supported by the government’s research and development investments, the leading PVM technology, termed wafer-based crystalline silicon (c-Si), is technologically mature with large-scale c-Si module manufacturing capacity in place. c-Si systems are likely to dominate the solar energy market for the next few decades and perhaps beyond. Moreover, if the industry can substantially reduce its reliance on silver for electrical contacts, material inputs for c-Si PV generation are available in sufficient quantity to support expansion to terawatt scale.
However, current c-Si technologies have inherent technical limitations-most importantly, their high processing complexity and low intrinsic light absorption (which requires a thick silicon wafer). The resulting rigidity and weight of glass-enclosed c-Si modules contribute to BOS cost. Firms that manufacture c-Si modules and their component cells and input materials have the means and the incentive to pursue remaining opportunities to make this technology more competitive through improvements in efficiency and reductions in manufacturing cost and materials use. Thus, there is not a good case for government support of R&D on current c-Si technology.