Prof D Chandrasekharam

“”The nation that leads the world in creating new sources of clean energy will be the nation that leads the 21st century global economy”” ….. Barack Obama, President of  USA. 

“We have an ambitious agenda to put millions of people to work by investing in clean energy technology like geothermal and solar energy……” Steven Chu Energy Secretary, USA.

There are two perennial energy sources that are available to all the living beings on Earth ever since Earth was born about 4.5 billion years ago. Till now these sources never failed and will continue till human race want. Sun and Earth are like furnace transmitting heat to the surface of Earth.  Unlike coal, oil and gas, these sources will never deplete. Its depletion means– the end of human race. Life will disappear like the dinosaurs once Earth and Sun ceases to supply energy. The energy from these two sources is clean. Countries have realized this fact and started harnessing geothermal since 1904 when the first electric bulb glowed in Larderello. Over the years geothermal energy stared contributing to the electricity demand in a small way and now its contribution is greater than 10,000 MWe. With constant development in surface and subsurface technologies, countries have realizing that energy independence is better than energy security and investing more in to this green power. Wet geothermal systems may be limited in geographical extent but enhanced geothermal systems ( also know as engineered geothermal systems or hot dry rock systems etc) have no such boundaries. Perhaps in future every housing colony, super malls etc. may have its own independent electric supply systems through EGS.  France has successfully experimented and showed to the world how to create natural heat exchanger within granites. Australia will be the second country to tap this source.   India has large EGS resources waiting to be tapped.  

 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.

 “……….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 Economist” dated 2 Sept. 2010. 

This year, President Obama announced $350 million to expand and accelerate the development, deployment, and use of geothermal energy throughout the United States. This funding will support projects in four crucial areas: geothermal demonstration projects; Enhanced Geothermal Systems (EGS) research and development; innovative exploration techniques; and a National Geothermal Data System, Resource Assessment and classification System. $ 140 million is allotted to support demonstrations of cutting-edge technologies to advance geothermal energy in new geographic areas, as well as geothermal energy production from oil and natural gas fields and low to moderate geothermal resources. $ 80 million is allotted to support research of EGS technology to allow geothermal power generation across the country. Conventional geothermal energy systems need wet geothermal sources while EGS makes use of available heat resources through engineered reservoirs, which can then be tapped to produce electricity any where. $ 100 million is allotted to support projects that include exploration, site location, drilling, and characterization of a series of exploration wells. Exploration of geothermal energy resources can carry a high upfront risk. By investing in and validating innovative exploration technologies and methods, Department of Energy, USA, can help reduce the level of upfront risk for the private sector, allowing for increased investment and discovery of new geothermal resources.

 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.