According to reports, after decades of studies and field surveys, India has finally decided to focus on tapping clean and renewable geothermal energy, which is available in abundance but remains largely untapped.
Union Ministry of New and Renewable Energy (MNRE) recently drafted a national policy, which seeks to make India a global leader in the sector, generating 1,000 MW in phase-one, ending 2022. The draft would be presented at the first global investors’ meet on renewable energy, to be held in New Delhi from February 15-17. Leading foreign firms in geothermal sector are expected to attend this meet.
“The power generated could be used to electrify rural parts of the country,” says Girish Kumar, scientist and head of the geothermal division, MNRE.
Anywhere on earth, below the surface there is tremendous amount of heat. This earthen heat can form a major power source. Although ambient temperature in India varies drastically from -10 degree to 50 degree centigrade, temperature below earth in geothermal zones could be as high as 150-160 degree centigrade.
Mile-or-more-deep wells can be drilled into underground reservoirs to tap steam and very hot water that drive turbines that powers electricity generators. Besides, geothermal energy can be used for heating and cooling purposes also.
Studies for locating renewable energy source were undertaken by the Geological Survey of India over the last three decades after which around 340 hot springs were traced. This includes geothermal reservoirs at Puga (J&K), Tatapani (Chhattisgarh) fields on Narmada, Godavari basin, Manikaran (HP), Bakreshwar (West Bengal), Tuwa (Gujarat), Unai and Jalgaon (Maharashtra) etc.
Chhattisgarh government has already decided to establish the first geothermal power plant in the country at Tattapani in Balrampur district, along with NTPC. This is the most promising geothermal resource in central India.
Though the capital cost involved in geothermal power plant is high due to costly exploration and drilling process, the power production is cheaper than the solar power plant. “A one MW geothermal plant costs Rs 30 crore (as per international estimate) while a solar power plant of similar capacity costs Rs 7 crore. However, geothermal energy is available 24/7 so the total power production is almost five-times more as compared to the solar plant,” says Kumar.
The geothermal power plants have almost zero emission.
The Union Ministry of New and Renewable Energy (MNRE) has assessed the potential of generating 10,600 Mwth from 340 hot springs spread across seven geothermal provinces in 11 states.
According to Girish Kumar, scientist and head of the Geothermal Division, MNRE, the power generated could be used to electrify rural parts of the country, especially for the cold-storages. “Though the technology to generate power from geothermal energy is available, it is very site-specific; so major thrust of the proposed policy at present is on exploration, research and development of efficient pumps.”
To encourage the industrialists, a 30 percent subsidy on capital has been proposed for the installation of geothermal projects. For research and innovation purposes, a whopping 50% of subsidy has been proposed. However, the allocation for the sector could not be obtained immediately.
Geothermal energy is heat stored in earth crust and being used for electric generation and also for direct heat application worldwide from last 50 years.
Though India has been one of the earliest countries to begin geothermal projects way back in the 1970s, but at present there are no operational geothermal plants in India. There is also no installed geothermal electricity generating capacity as of now mainly chief because the availability of plentiful coal at cheap costs. “However, with increasing environmental problems with coal based projects, for the first time the Centre has decided to use this source,” said an official from the ministry.
Among 24 countries using this technology are USA, Sweden, Germany, Switzerland, Canada, Japan and China with world production of 12,000 MW power. The largest producer of this environment friendly electricity is USA that generates 3,086MW of electricity. Moreover, at least 78 countries use this energy for direct heating.
The scheme is open to public and private sector to carry out projects in India. For geothermal power exploration, the entrepreneur is supposed to approach the state government for site allocation. Centre aims to provide research grant to the applicants. Research institutions, universities can also apply. All stake holders like HVAC Contractors & Suppliers, Food Processing Units Manufactures Builders & contractors, Cold storage, Green House Manufacturer, Hotel/Restaurants Owners, Industry owners, Social Institutes, Schools Owners are encouraged to come forward for deployment of geothermal pumps. For industrial projects it would 30% of the capital cost and 30-50% for the research, design and development work and up to Rs 50,000 for public good like space heating, greenhouse cultivation, cooking etc, using direct geo-exchange pumps.