Prof D Chandrasekharam

“Deriving energy from subterranean heat is no longer limited to volcanic regions. By drilling deep wells into the ground, it can be made to work almost anywhere. Engineered geothermal systems (EGS) are based on a related principle, but they work even in parts of the world that are not volcanically active, by drilling thousands of meters underground to  mimic the design of natural steam or hot-water reservoirs. Wells are bored and pathways are created inside hot rocks, into which cold water is injected. The water heats up as it circulates and is then brought back to the surface, where the heat is extracted to generate electricity. Because the Earth gets hotter the deeper you drill, EGS could expand the reach of geothermal power enormously and provide access to a virtually inexhaustible energy resource” states a news item on “HOT ROCKS AND HIGH HOPES” (Inside story) in “The Economist” dated 2 Sept. 2010.

 Geothermal systems are based on circulating hot water, heated either by volcanic or tectonic ( deep continental rifts) systems. Such system where natural rain water circulates is known as wet geothermal systems.  As on today, according to the recently concluded “World Geothermal Congress 2010,  10,700 MWe of power is being generated from geothermal energy supplying 85 million Gwhr of electric power.                                                           

The future energy need of all the countries will be met with by EGS systems.  For example, 2% of the energy (EGS) if tapped will be sufficient to meet the energy demand of United States of America, according to “  The Future of Geothermal energy “ of MIT 2006. Currently  Soultz EGS systems has started functioning successfully. This will soon be followed by the EGS system in the Cooper Basin of Australia.

 “……….Over the next decade Geodynamics plans to build ten 50 megawatt (MW) power stations in Cooper Basin, and that may just be the beginning. According to Doone Wyborn, the company’s chief scientist, the area’s resources could support  hundreds of power stations with a total generating capacity of up to 12.5GW—more than all the geothermal power stations now operating worldwide……………… These benefits, in combination with growing electricity use worldwide, concerns about limited supplies of fossil fuels, and efforts to reduce carbon-dioxide emissions and prevent climate change, have prompted governments and investors to pour money into this emerging technology. Google, for example, has invested more than $10m in two EGS companies in California, Potter Drilling and Alta Rock Energy. Meanwhile America’s Department of Energy has announced up to $338m in stimulus funds for 123 geothermal projects, with nearly $133m earmarked for EGS research……………………” states  the above magazine.

 EGS technology is more or less well established. Following France and Australia other countries like Germany and England are lined up to harness this heat. 

 India is not lagging behind EGS resources. Perhaps, India has the richest EGS resources considering the volume occurrence of high heat producing granites.  About an year ago, in a publication entitled “ Granites and granites: India’s warehouse of EGS” in Geothermal Resources Council’s Bulletin followed by a recent proceedings published by the World Geothermal Congress 2010, it is stated “ Assessment has been carried out on the power producing capacity of thee granites using the U, Th and K content. For example, estimates on a small volume of granite from northern India indicate that they have the potential to generate minimum of 61160 x 10¹² kWh. Perhaps EGS, in future, may make India energy independent and wipe out the 78,577 MWe deficit.  Considering the total surface exposure of such high heat generating  granite over the Indian subcontinent (150000 sq. km), their depth of occurrence and the stress regime of the Indian plate Indian granites will be future warehouse of EGS…………… Indian government has realized this potential and making efforts, through slow, in bringing geothermal under the primary source mix. India in future can  disprove the IEA (2007) report that it will a major coal importer in 2030 if its geothermal resources are judiciously utilized not only for power generation but also in building and food processing sectors”…………states these publications.

Andhra Pradesh has surged forward in promoting geothermal power by signing Power Purchase Agreement with GeoSyndicate. Green energy initiative taken by the Govt. is an example of how the state is planning to reduce the carbon foot print and implement  clean development mechanism. Dynamic leadership and vision for future energy independence made this historic event.  Read the press release:

“Mumbai, Aug 31 (PTI) India’s fist Geothermal power plant with an initial capacity of 25 Megawatts will be coming up in Andhra Pradesh’s Khammam district by 2012, an official said today. India’s first Geothermal Power Purchase Agreement (PPA) between GeoSyndicate Power Pvt Ltd (an incubated company of Indian Institute of Technology, Bombay) and Northern Power Distribution Company of AP Ltd (APNPDC) was signed recently in this connection, Dr D Chandrasekharam, Founder and Chairman of Geosyndicate told PTI here today.

The signing of the agreement was done under the aegis of the Non-conventional Energy Development Corporation of Andhra Pradesh Limited (NEDCAP), he said.

Andhra Pradesh is the first state in the country to have executed this PPA with India’s one and only Indian geothermal company with eminent scientists and technocrats on its board, Chandrasekharam said.

Global warming and climate change is and will continue to be one of the key challenges the world has to face in the coming decades and “Geothermal energy could play a vital role in mitigating these challenges by reducing dependence on fossil fuels and provide clean energy,” he said.

GeoSyndicate looks forward to play a significant role in reducing the country’s carbon foot print by setting up the Geothermal plant, he added.””

Developed and developing countries are focusing more on energy independence to progress fast with developmental activity and to bridge the gap between demand and supply with respect to all essential commodities like power, water and food. Too much dependence on imported fossil fuel to support economic growth will push the country back words. With the advancement of drilling and heat exchanger technology it is becoming easier for the developing countries to harness their huge low enthalpy geothermal energy resources. Although India fell behind in catching up with geothermal resources, it has now realized the importance of all renewables and surging ahead with available technologies to reduce carbon dioxide emission. 

 Compared to all the countries, OECD Europe is expected to increase renewable energy share in its power source mix from the current 19 to 23%. Europe is already at the top of low emission countries list and currently trading carbon at the rate of ~ 8-10 euro under CER). India is a major customer (China tops the list) for carbon trade with Europe and continue to be so for the next decade, considering the future power demand and generation of power from coal based thermal power plants. By the 2030 India will be fully under the control of Europ with huge piled up credit. Both wind and geothermal are playing a major role in primary source mix in Europe’s power scenario. But this situation can be over come if India utilizes its geothermal energy sources.

Geothermal energy resource can provide a stable supply of energy, in contrast to many alternative domestic renewable energy resources like hydro, wind and solar photo voltaic in all the developing countries like India. If such sources are not utilized to the fullest extent, then the carbon emissions in the non-OECD countries will only see an upward trend unlike the OECD countries

On an average, geothermal power plants emit 0.893 kgCO₂/MWhr while coal power plants emit 953 kg CO₂/MWhr. The combined (wet low enthalpy and EGS) geothermal potential of India, taking into account the150000 sq. km high heat producing granites, spread over the continent extending from the HGB to the southern part of the continent, on a conservative side amounts to 18348 x 10¹⁴ kWhr

Further, 33% (245 x 10⁶ MWhr, only coal power) of electricity in India is utilized by the building sector (commercial and domestic). A major amount is spent for space cooling, refrigeration and hot water supply. This amounts to emission of 234 x 10⁹ kg CO₂. If India utilizes low enthalpy geothermal sources (through GHPs) and save additional revenue of 234 x 10⁷ euros under CER

In addition to the building sector, implementing CDM in food processing sector also will provide additional benefit to the country in reducing CO₂ and earning carbon credits.

Indian food sector uses about 13 % of the electricity (IEA, 2007) amounting to 63 x 10⁶ MWhr (from coal fired thermal power plants). Thus part of the capital, amounting to 600 x 10⁶ euros can be raised through CDM and ploughed into this industry by using geothermal sources instead of conventional fuels.

( for more details read: Energy Independence Through CDM Using Geothermal Resources: Indian Scenario, Proceedings World Geothermal Congress 2010, Bali, Indonesia, 25-29 April 2010).