Harnessing of Low Enthalpy Geothermal resources Using Integrated Techniques

Abstract

The ever increasing energy demand and environmental pollution caused by conventional energy resources forced countries to give special emphasis on developing renewable and cleaner energy sources like geothermal energy. Geothermal exploitation of India is still in the nascent stage. The main reason for this is majority of the high enthalpy geothermal resources are at remote areas especially in Himalayan zone. But India has a large number of low enthalpy geothermal resources which can be exploited for both direct utilization and electricity generation. The prime objective of this project is to find a strategy for effective exploration and exploitation of low enthalpy geothermal resources. Extensive literature survey has been carried out as a part of the project to understand the different exploration and exploitation methods used for low enthalpy geothermal resources around the world. The site Dholera is chosen based on the exploration activities already carried out in the region. Different geophysical exploration methods like Magnetotelluric Survey, Seismic Survey and Gravity Survey are carried out at Dholea for understanding the geothermal reservoir. The results of these survey methods are also integrated. Both shallow and deep exploration activities are discussed, which aims at giving a better understanding of geothermal reservoir. To access the geothermal reservoir, shallow wells are drilled. SP and Resistivity Logging are also conducted for borehole investigation. Surface and subsurface exploration data are also integrated for better understanding and confidence. Effective exploitation strategy was prepared based on the exploration results. One of the major challenges in exploiting the shallow geothermal reservoir at Dholera was the temperature limitation.