Commentaries

Solar Energy: Alternative to Combat Energy Insecurity in India

Shikha Bisht & Biswajayee Patra
December 12, 2006

With a growing economy and increasing population, India’s energy demands are mounting. The household sector is the largest consumer of energy in India, accounting for 40-50 per cent of the total energy consumption in the country. In rural areas, the domestic sector accounts for nearly 80 per cent of total energy consumption. It has been estimated that with the current rate of consumption, India would require over 450 million tones of coal, 94 million tones of oil and 220 million units of electricity by 2006 to sustain its energy needs. Most of these sources are non-renewable resources and are therefore unsustainable. Thus the need is felt to shift over to renewable sources of energy, and these sources of energy should be utilized keeping in view the point of sustainability.

India has long ago realized that the key to sustainable consumption is to divert the energy load onto renewable sources, which is evident by looking at the status of renewable energy use in India. More than 3165 MW of power generating capacity based on renewable energy sources have been installed. India has the world’s largest deployment of solar PV (Photovoltaic), consisting of 850,000 PV systems aggregating 50 MW. India ranks 3rd in annual production capacity of solar PV (17 MW) ahead of Germany, France and Australia. With over 3.23 million biogas plants installed, India ranks 2nd after China. There still exists a potential of about 3500 MW of biogas-based power from 453 sugar mills in India. With 1367 MW of installed capacity for wind power, India ranks 5th globally with a total installed capacity of 18710 MW.

The ultimate source of sunlight on the earth's surface is the radiation received from the sun. Here the sunlight received is converted directly into electricity using photovoltaic (PV) cells. This resource is especially valuable for tropical countries like India, where there is adequate sunshine available for most parts of the year and most of the time. The amount of solar energy impacting the earth's surface is 1000 watts per square meter, which is about 32.8 million MW every second on the Indian landmass. A large part of the incident heat is reflected in outer space or radiated back to space. 

Considered from a practical viewpoint, solar energy is inexhaustible. It is also widely distributed, environment friendly and cost-free in raw form. Partially offsetting these manifold benefits are two technological disadvantages: Low intensity or dispersion and unpredictability, which varies with the whims of weather. Nonetheless, solar energy can supply from 40 to 75 per cent of a building’s energy needs, requiring only supplementary sources.

Harnessing the sun’s light and heat is a clean, simple and natural way to provide hot water or spaces heating in household and commercial buildings. There is another way to produce power from the sun through photovoltaic cells that convert solar radiation directly into electricity. Solar energy can be used for regulating the temperature of the dwellings by capturing the heat from the point where the radiation falls and directing it to the places where it is needed.

‘Solar architecture’ or the solar efficient building design is a climate-responsive architectural concept in which the impact of climate is minimized both in summers and winters, leading to the reduction in the use of electricity or other artificial energy sources. Unlike the conventional design approach that treats climate as the enemy which has to be kept out of the building environment, solar architecture endeavours to build dwellings as a part of the environment, using climatic factors to our advantage and utilizing the energy of Nature itself to attain required comfort levels. Nature’s energies can be utilized in two ways- Passive and Active and consequently, solar architecture is classified as Passive Solar and Active Solar architecture. 

‘Active Architecture’ methods employ a solar collector. Air systems use collectors, thermal storage bins filled with gravel, and ductwork to transport the heated air. In ‘Passive Architecture’, a solar heating or cooling system is passive if energy is collected, stored and distributed by natural forces, without mechanical aids or elaborate hardware. 

The Indian government has taken the initiative to promote this universally available cost-free resource – Solar Energy. Besides arranging seminars regularly, the Indian Renewable Energy Development Agency (IREDA) - a Public Limited Company established in 1987- provides revolving funds to financing and leasing companies offering affordable credit for purchasing PV systems, which in turn service lower volume customers. IREDA has also launched the Renewable Energy-Energy efficiency Umbrella Financing Scheme for organizations with good existing networks to serve individual/retail customers who do not fulfil IREDA’s legal eligibility criteria and are scattered over large rural/semi-urban areas. The scheme provides a loan of up to one crore at a very low interest. Both Ministry of Non-Renewable Energy Sources (MNES) and IREDA have taken extensive measures to create awareness about Renewable Energy Products and Services, resulting in the creation of a substantial market for these products. IREDA has also launched a scheme to set up energy centres across the country to serve retail consumer segments. Soft loans are provided at low-interest rates to establish the solar water heaters for a period of 6 years. These also include an 80% depreciation tax for profit-making companies.

Usually, people are hesitant regarding the use of solar energy. It is perceived as an emerging field, and hence tendency amongst the researchers is lacking to take that as a full-time profession. As well as, the commoner is not looking at solar appliances as a replacement for their existing heating gadgets like solar cookers, solar lights, solar heaters etc. This, in turn, is stopping the industry from investing in this technology. But in reality, solar energy is one of the oldest resources available, and our ancestors had a fairly good idea about the importance of this resource. They used to keep in mind the possible usage of the energy, which is available to us in plenty and distributed freely. Providing low-cost, environment friendly and sustainable energy to every rural household has been the top priority of the successive Indian governments. Only the political and practical will is necessary for the encouragement of solar energy in India which in return supplements the energy Independence of India.

Author Note
Biswajayee Patra is a New Delhi based Application Scientist. Sikha Bhist is a project associate with Delhi based School of Planning and Architecture.