Small Scale Geothermal Development Potential for Island Nations Situated Along the Pacific "Ring of Fire"

Abstract

Geothermal energy has a great potential for meeting the electrical and thermal energy requirements of many countries and territories lying along tectonically active zones within and surrounding the Pacific Basin. Energy requirements for many of the small, scattered island nations preclude development of conventional generating facilities large enough to incorporate any economies of scale. However, by attempting to discover and develop shallow, relatively low temperature, geothermal reservoirs associated with recent vulcanism on many of these island nations, exploration expenditures and risks, and problems associated with the development of high temperature resources can be reduced. Exploration and development drilling for these resources can be accomplished with truck mounted rotary drilling rigs that are less costly and more suitable for operations within the island infrastructures than the conventional rigs normally used in the drilling of deep, high temperature geothermal resources. Experience over the past decade with small, modular, binary (Rankine) cycle generating units indicates that geothermal energy can provide a reliable source of baseload electricity in the amounts required and at a cost that is competitive with other alternative energy sources. Development of shallow, moderate temperature, geothermal resources with small, modular binary cycle generating units can provide ideal additions to the energy sources of many of the Pacific island nations within the framework of their island economies.