The four pillars of non-conventional energy

After initial success in deriving energy from water, sun, wind and biomass, India is poised for a great leap in making these the energy sources of the future.

 
Last Updated: Sunday 28 June 2015

The four pillars of non-conventional energy

-- Mini-micro hydel:
Indian technologists developed mini-hydel systems more than 100 years ago, but in the post-Independence emphasis on the new "temples of modern India" -- huge dams and power stations -- mini-micro hydel systems were neglected. In 1989, however, hydro projects below 3 mw were transferred from the power ministry to MNES because it was felt that small-scale systems need to be dealt with differently. Former CPWD director general C Rama Rao says micro-hydel systems promoted by the Central Electricity Authority require extensive civil construction and, therefore, are costly. But a Chinese design cuts cost drastically and was adopted in some of the northeastern and Himalayan states.

Small companies such as Flovel Private Ltd and Triveni Engineering Works, both in Delhi, and Boving Fouress (P) Ltd, Bangalore and Jyoti Ltd, Vadodara, manufacture mini-micro hydel generators, controls and allied equipment. BHEL has also developed hydro-electric equipment and controls. All these companies use highly indigenised technology.

The Eighth Plan committment to this energy sector is Rs 100 crore. In addition, the World Bank will provide Rs 210 crore and the GEF, Rs 220 crore, for small-scale hydel promotion in the hilly regions of Uttar Pradesh and Himachal Pradesh. A World Bank stipulation that loans will be available to only private firms, cooperatives and public sector undertakings (except generating companies), is intended to encourage their participation in these projects. A World Bank-MNES study in 1991 identified 45 potential sites in the four south Indian states and Punjab for small-scale hydel projects with a total capacity of 110 mw. The study's objective was to simplify design, standardise equipment and reduce costs.

Photovoltaic systems:
MNES advisor J Gururaja says his ministry's programme for the deployment of solar photovoltaic systems "constitutes one of the largest government demonstration programmes in the world". Public sector organisations involved in this effort maintain the growth rate of the Indian photovoltaic market is among the highest in the world. Senior marketing officials of Central Electronics Ltd (CEL), of Sahibabad in Uttar Pradesh, and BHEL expect this to increase 12-fold in the next few years. About 30 per cent of the photovoltaic installations are commercial, unsubsidised and in such areas as telecommunications, signals, defence and oil exploration. MNES' photovoltaic programmes are used to provide domestic and street lighting and water pumping. They rely primarily on government subsidies.

The production of photovoltaic cells increased by 30 per cent per annum in the last decade. CEL reported last month that production of monocrystalline solar cells and modules reached a level of 1.25 mw. The level is a record "indicative of a breakthrough in large-scale use of solar photovoltaic systems in the country," according to CEL sources.

An installed capacity to manufacture 2 mw makes CEL one of the top five manufacturers of solar photovoltaic modules worldwide. BHEL, Bangalore, whose established capacity is 1 mw, is the other leading manufacturer of photovoltaic cells and ranks among the top dozen manufacturers of solar cells and solar systems.

Rationalising of the duty and tax structure for photovoltaic cells and modules is encouraging private companies to enter the industry. British Petroleum Solar representative Andrew Peers says, "With the likelihood of $ 55 million in World Bank assistance for the photovoltaic industry directed to market development, several multinational firms are eyeing the Indian market."

Bangalore-based Tata BP Solar, one of the leading private sector companies, has been manufacturing photovoltaic modules and systems since 1992 and intends to set up a manufacturing line for solar cells. Says chief executive A K Vora, "The ratio of imported to indigenous cells is 80:20 now, as against 50:50 before."

In an effort to bring down the cost of photovoltaic cells, made conventionally from single-crystal silicon, MNES has been working since 1989 on developing amorphous silicon. BHEL has set up a 500-kw-per-shift pilot plant for MNES at Gwal Pahari near Delhi for the manufacture of amorphous silicon (A-Si) modules. BHEL director for engineering R & D K Ramakrishnan says, "Commercially obtained efficiencies of A-Si panels is only about 7 per cent per square foot against more than 15 per cent for crystalline silicon, but the former has low input costs and so lower manufacturing costs". Their main drawback, he adds, "is that the panels degrade fast. (But) our scientists are confident that this degradation can be reduced and its functional life increased."

Wind energy technology:
Wind energy churned out by grid- connected wind farms has turned out to be the most feasible and cost-effective method of power generation. Its current level is about 45 mw but MNES' target by the end of the Eighth Plan is 100 mw.

Rakesh Bakshi, director of Vestas RRB India Ltd, a New Delhi manufacturer of wind energy equipment, says, "Wind farms have become a viable proposition because state electricity boards, especially in Gujarat and Tamil Nadu, have introduced a system of wheeling and banking of wind power." This system allows private investors to set up wind farms in a favourable location and feed power into the state grid and then withdraw an equivalent amount from it later. "However, state boards still have to work out a viable and attractive price for the electricity purchased," adds Bakshi.

Also being tried out are more than 2,500 wind pumps and 200 kw of wind-diesel or autonomous systems, wind battery chargers and stand-alone wind electric systems.

BHEL, the largest domestic manufacturer of wind turbines, is the leader in indigenised wind generators, which have grown from 55 kw size to generators of 200-500 kw capacity. Natural Energy Processing Co of Madras also says it has achieved significant indigenisation in manufacturing generators and fabricating the tower and other ancilliaries. Ajit K Gupta, director of the solar energy centre of MNES, notes, "Wind energy is a clear example of Indian firms taking technology from abroad, altering it to suit our conditions and then developing an industry based on the altered design. The Eighth Plan will generate sufficient demand for at least five manufacturers, in both the public and private sectors, to take up regular production of wind electric generators.

Cannon Energy Corp of USA has offered to set up a Rs 350-crore wind farm project of 110 mw capacity in Anantapur district, Andhra Pradesh. If the project, headed by an NRI, is cleared, it will be the largest in Asia.

Nevertheless, Bakshi complains, "Tariffs and duties for wind energy are higher than that for conventional power. Even in the current budget, greater concessions are given to conventional power than to wind electric generators. Why is the government discriminating against a pollution-free source of energy?"

Biomass gasification:
Agricultural residue, agro-industrial waste and energy plantations are available in quantities which would justify their use for power generation. Even with presently available conversion technology, biomass can be use to provide electricity and heat efficiently.

B C Jain, director of Ankur-Energy and Development Alternatives, Vadodara, points out, "When a programme of biomass production is coupled with its conversion for energy purposes there is no net CO2 release as is the case with conventional power generration. This aspect is very well recognised the world over and this technology is recommended as one of the few option to arrest global warming." The capital intensity of biomass conversion technologies is a low Rs 10,000/kw of installed capacity, whereas a 200 mw thermal power plant requires at least Rs 14,000/kw, he adds.

MNES sources estimate the likely exploitable power generation potential by 2000 from biomass obtained from agricultual and agroindustrial residue, will be the equivalent of more than 17,000 mw -- and could be even as high as 60,000 mw. More than 1,000 biomass gasifiers have been installed so far.

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