Optimizing Integrated Energy Resources on a Small Island Power System with Predominantly Geothermal Power

Abstract

In an effort to reduce dependency on fossil fuels for power generation, several Caribbean islands have recently sought to exploit their indigenous geothermal resources. Traditionally geothermal plants are used for base load generation. However small island states load demand profiles characteristically have significant intra-hourly variations which would require rapid changes to geothermal plant power output that may be more economically handled by other power sources and balancing mechanisms. The paper examines various scenarios of future energy resource integration together with grid and energy management technological development on the Caribbean island of Nevis. The main objective is the displacing of diesel generation with baseload geothermal energy. Using simple power system models and simulations, the paper proposes designs and stepwise development toward improving the efficiency, sustainability, flexibility and stability of the Nevis island grid. The paper shows that geothermal energy integrated with other renewable resources, along with modern grid and energy management technologies, allows for the realization of reduced energy costs, improved energy security and environmental conditions for the island of Nevis. The findings are also applicable to other islanded power systems or grids with weak connection to a main grid.