Having heard about the interest of Sri Lanka to utilize its geothermal resources before, this article caught my attention. Written by Dr. H.A. Dharmagunawardhane, aSenior Lecturer in Hydrogeology & Applied Geophysics, Department of Geology, University of Peradeniya, the article makes a case for developing geothermal resources in the country. For the complete article and a picture on thermal springs in the country, see link provided for below.

The article talks about the hidden geothermal resources of the country and that “The country’s potential for hydro-electric power generation has already been largely exploited, but what of the hidden geothermal energy in the subsurface in the areas of the 10 hot-water springs which so far have only been used for bathing due to their medicinal and healing properties including the therapeutic power for skin conditions and rheumatic arthritis?

Medicinal bathing is popular at the Mahapelessa spring.in the subsurface in the areas of the 10 hot-water springs which so far have only been used for bathing due to their medicinal and healing properties including the therapeutic power for skin conditions and rheumatic arthritis? Medicinal bathing is popular at the Mahapelessa spring.

These hot water or thermal springs along a narrow belt running from Hambantota to Trincomalee occur within the boundary of two main geological units — Highland and Vijayan complexes. These springs are surface manifestations of subsurface hidden heat (energy) sources such as huge bodies of ‘hot dry rocks’, ‘deeply extending fracture zones’ or concealed magma chambers’.

However, since Sri Lanka is not in an active volcanic or tectonic region of the earth crust, magma chambers can be ruled out.

The temperatures of the thermal springs range from 350 to 610 Celsius (I assume the author means 35-61 degrees Celsius) and only limited preliminary scientific studies have been carried out so far, while no detailed geological studies, geophysical exploration and test-drilling have been conducted.
Prospects of low to medium temperature geothermal resources can be spread over the thermal-springs belt in Sri Lanka. There is also potential for direct-use applications in the food processing, fruit drying, refrigeration, fish hatchery and farming, recreation and tourism spheres.

Geothermal energy is not dependent on the weather unlike solar, wind or hydro power. Therefore, potential geothermal energy reserves in the country could probably provide (if not fully) at least part of the electricity requirements.

However, to develop the potential geothermal prospects for industrial exploitation, systematic geological, geochemical and geophysical techniques are required to locate and delineate shallow producing geothermal fields. Such work will pinpoint with accuracy the particular depths of hot-water reservoirs for drilling exploratory investigation boreholes.

A major exploration effort is needed to characterize geothermal reservoirs and prepare an inventory of potential geothermal areas for further development.

As this is one of the most environmentally clean and friendly sustainable renewable energy sources, Sri Lanka may also be able to get financing under the Clean Development Mechanism (CDM) promoted by the Kyoto Protocol, which encourages developed countries to invest in renewable energy projects in developing countries. The greenhouse gas credits created by geothermal power plants could be sold on global markets to bring extra cash revenues.”

The author then concludes that “Sri Lanka, therefore, should make a strong commitment to develop these geothermal resources.”

Source: The Sri Lanka Sunday Times