Geothermal development and forecasting for space heating and electricity generation

Iceland is a country with one of the the highest development of geothermal energy in the world. Geothermal energy is used expensively for space heating in the cold climate of Iceland, in addition to using it for electricity generation. The paper presents a survey of this development, current status and future prospects, both the widespread use of geothermal energy for residential space (district) heating, and its history, especially in urban communities. The phenomenally rapid development in electricity generation is also reviewed. The paper also discusses briefly the international situation in geothermal energy and describes the role of geothermal energy in the fuel substitution process in Iceland since the early 20th century. We also characterize major geothermal high temperature areas, their potential output and locations, based on the underlying geological aspects. Furthermore, the paper presents geothermal energy forecasts and forecasting methods, in particular those published by the public Energy Forecasting Committee (EFC) with the mandate, since 1978, of forecasting future energy use, including the geothermal component. Geothermal electricity generation's share in world electrical generation has been approximately constant in the last two decades but grown explosively in Iceland. We review this high growth of geothermal electricity and the developed high penetration of space heating and industrial use in Iceland. This will cast light on the importance of geothermal energy in this very important "geothermal country" of Iceland in international context.