Archive for October, 2013

01
Oct
13

EGS…..where we stand

According to the latest issue “Electric Power Monthly” published by EIA, until June 2013 renewable provided 14.2 % of net electricity compared to the same period last year globally (13.57%).  It is an encouraging news though it is not a quantum jump. Geothermal is catching up with a growth rate of 1% from 0.43%. Coal still rules the roost with 39% followed by oil and gas at 26%. Job market is high for the renewables with 166 jobs being announced for geothermal. This is natural since technology to drill deep into earth’s crust has advanced and drilling to depth of 3 to 4 km in hard-rocks has become an easy task.

Packers Plus Energy Services Inc., in collaboration with Geodynamics Limited, designed  specialized equipment that is  capable of withstanding 300°C and 69 MPa pressure.. This is a tremendous technology development that makes future EGS project more lucrative. This equipment is a “must” for EGS developers, which involves stimulation into the existing low permeability fractures in rocks with high temperature. Suitable especially for the high heat generating granites. The Geodynamics have started generating 1 MWe through EGS from Habanero well 4 which taping the heat from about 4.2 km in granite.  With the commissioning of Habanero and Slutz plants, it is now certain that electricity can be generated from deep granites anywhere on the earth. This is a break through: the amount of energy available in these granites is enormous. To count a few, Indian granites have the potential to generate energy equivalent to 3.133 x 1022 BTU.  Even if 2 % of this energy is tapped, the country’s electricity deficit can be wiped-out in a short period of time. Once such perennial, based load power is available, then this automatically increases the GDP, socio-economic situation of the countries, reduces CO2 emission in a big way and controls the  micro climate system.

Experiments on fracture pattern in Bundelkhand granites at different temperatures ( 300 °C) and pressures (60 MP) have yielded interesting results and are encouraging. These granites buried below the Deccan volcanic flows and Gondwana sediments at depths varying from 2 to 3 km recorded temperatures varying from 160 to 200 °C.  Similarly, the Rajasthan granites recorded heat generation value over 17 µWm-3, perhaps the highest ever recorded for granites from central Indian province. The heat flow value obtained here is greater than 100 mWm-2. These are treasure energy sources that will mitigate CO2 emissions from fossil fuel based  power plants and secure energy for the economic growth of India.  If developed, the EGS source will help India to reduce CO2 emissions to a large extent.   As has been reported earlier in World Geothermal Congress 2010 at Bali, India provides  excellent opportunity to initiate experimental EGS projects in several parts of the country. Unlike other energy sources like wind, solar pv and nuclear, this energy source has no issues related to land requirement, health and environment and baseload power supply.  The challenges that geologists faced in 2000 are now addressed by technological development and now only the technology needs fine tuning. Geodynamics has mastered the technology and are going global.  Energy for our future generations is secured. This will happen soon. Every country will be  energy independent  in the next century.

 

A recent publication, “The Future of Geothermal Energy – Impact of Enhanced Geothermal Systems (EGS) on the United States in the 21th Century“, determined a large potential for the USA: recoverable resources > 200,000 EJ, corresponding to 2,000 times the annual primary energy demand. An EGS power generation capacity of >100,000 MWe could be established by the year 2050 with an investment volume of 0.8 – 1 billion USD. This publication presents marketable electricity prices based on economic models that need to be substantiated by EGS realizations. Since the temperature increases with depth everywhere, in future EGS could generate electricity in our backyard! The technology is being perfected with the commissioning of 1.5 MWe pilot EGS power plant in France and as said above 1 MWe in Australia.  EGS plants, once operational, can be expected to have great environmental benefits (negligible CO2 emissions. See figure below).

New Picture (4)

 

 

Some environmental issues like the chance of triggering major earthquakes  is unfounded. There is an ongoing media hype about earthquakes possibly being induced by EGS projects. One of the leading American Geothermal Company believes “fears to appear overblown”. Concerns about earthquakes are realistic, but from a public hazard point of view, the earthquakes should not be a big concern since the magnitude will be around 2 to 2.5 says United States Geological Survey Geologists. Human being will never feel such low magnitude earthquake even while stationary. Such small magnitude earthquakes will occur only during well stimulation period ( which will be about 2 weeks) that creates fractures for easy flow of the injected water.   In fact millions of earthquakes do occur across the world of this magnitude unnoticed by humans. Earth is indeed a dynamic systems and such events are normal. People should get educated on such fundamental truths. This is not a great barrier. Barriers like grid connectivity, capital investment, payback period and amount, tax benefits that hamper the growth of other renewables have little influence on geothermal source…………whether it is hydrothermal or EGS.  Geothermal can operate either on single large power grid system or it can operate on a local grid connected to small communities. Geothermal systems, unlike other renewables, can operate 24 x 7 with capacity to supply base load electricity. The life of a geothermal power plants is quite large……….the Larderello power plant that started in 1904 is still generating electricity!!  In geothermal, only drilling cost takes away nearly 45% of the CAPEX. But, the advantage is, once the field starts generating electricity, then there is no turning back.  In the case of other renewables, land takes away more than 60 to 70 % of the CAPEX and land acquisition runs in to political and  sociological issues. Geothermal power plants need 1 acre/MWe, while solar pv and wind need  7 and 3 acre/MWe respectively. Payback period in the case of geothermal is 4 to five years for a 20 to 25 MWe power plant. This a great advantage since financial institutions will be able lend large amounts for seting up geothermal power plants. This is not the case with other renewbles.  Large subsidies given to other renewables is not able to attract the financial institutions. Long  payback period is a deterrant to financial instutions.  In the case of solar pv, wind and geothermal, the source is free. But issues related to intermediate componants in the case of solar pv and Nd element in the cas of wind turbines bring geotehrmal in the driving seat. Thus a large capital expenditure is spent on R and D to develop low cost intermediate componants. Once the EGS  technology is pefected, major grid system of power distribution will be a thing of the past.  The biggest barrier in the case of geothermal is ‘mind set’.

Accarding  to the World Geothermal Congress report (2010),  the world is generating over 40,000 Gwh of electriciy and is projected to geenerate over 70,000 Gwh by 2015. Like “slow and steady wins the race” geothermal progressing at the rate of 4% / year. This is remarkable growth and soon this source will outbeat otherr renewable sources.

Geothermal power projects, typically  takes about 18 to 20 months to take off ( from exploration to drilling and powr plant comisioning). Drilling takes a large chunk of time. The market is hot now with dveloping countris, like East African rift countries and Central American countries, focusing on geothermal. Many of the geothermal companies are migrating to African countrirs leaving domestic market due to high expansion programme in African and MENA countries with the financial support from world financial institutions like USAID andd WORLD BANK.

Karl Gawell, executive director of the GEA, in a recent statement said that many developing countries have realized the potential of geothermal and decided to develop the same for two main reasons- 1). for economic growth and industrial growth these countries need uninterrupted electric power  and  2). many countries are introducing policies to reduce carbon dioxide emission. The geothermal market in MENA countries is upbeat and over one hundred geothermal companies from USA, Europe and South Asia are moving to East Africa to participate in bids for geothermal power project. These companies were engaged in domestic market about an year ago ! The project that were considered not feasible about five years ago are now becoming importation. Thanks to the advancement made in drilling and heat exchanger technology.  Low to medium enthalpy geothermal resources are attracting large number of investors globally,  As has been explained in the  book ” Low enthalpy geothermal resources for power generation” published by Taylor and Francis, the LEGR are cost effective and can support millions of rural population when connected to local grid system. Scientists and engineers in developing countries are converting “ideas” into “reality”. This will change the life of millions living in the rural areas who, in some countries like India, have not see an electric bulb.