18. Geothermal Power

  1. Prof. Detlef Stolten2,3 and
  2. Prof. Dr.-Ing. Viktor Scherer4
  1. Christopher J. Bromley and
  2. Michael A. Mongillo

Published Online: 21 JUN 2013

DOI: 10.1002/9783527673872.ch18

Transition to Renewable Energy Systems

Transition to Renewable Energy Systems

How to Cite

Bromley, C. J. and Mongillo, M. A. (2013) Geothermal Power, in Transition to Renewable Energy Systems (eds D. Stolten and V. Scherer), Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany. doi: 10.1002/9783527673872.ch18

Editor Information

  1. 2

    Forschungszentrum Jülich GmbH, IEF-3: Fuel Cells, Leo-Brandt-Straße, IEF-3: Fuel Cells, 52425 Jülich, Germany

  2. 3

    Forschungszentrum Jülich GmbH, IEK-3 Institut für En. & Klimaforschung, Wilhelm-Johnen-Str., 52428 Jülich, Germany

  3. 4

    Ruhr-Universität Bochum LS f. Energieanlagen, IB 3/126 Universitätsstr. 150 LS f. Energieanlagen, IB 3/126 44780 Bochum Germany

Author Information

  1. GNS Science, Wairakei Research Centre, Private Bag 2000, Taupo 3352, New Zealand

Publication History

  1. Published Online: 21 JUN 2013
  2. Published Print: 28 MAY 2013

ISBN Information

Print ISBN: 9783527332397

Online ISBN: 9783527673872



  • geothermal deployment;
  • enhanced geothermal system;
  • sustainability, resource assessment;
  • combined heat and power;
  • International Energy Agency;
  • Geothermal Implementing Agreement;


Geothermal energy for power generation has a mature history of sustainable use that extends back 50–100 years at several locations (e.g., Italy, New Zealand and the United States). Across the globe, however, it is a significantly under-utilized renewable energy resource. With a virtually unlimited global technical deployment potential, geothermal energy could potentially contribute 5–10% to global electricity needs by the next century. By 2050, the International Energy Agency (IEA) Geothermal Roadmap foresees an installed electrical capacity of 200 GW, providing 1400 TWh per annum, or ∼3.5% of global generation, and direct use of geothermal heat is anticipated to be sufficient to meet ∼4% of total heat energy demand, that is, 1600 TWh a−1. Ground-source heat-pump deployment, especially for heating and cooling of buildings, is expected to add even more. Assuming that this deployment displaces mostly coal-fired heating and power, the total reduction in CO2 emissions by 2050 from geothermal energy utilization could be substantial. Unfortunately, the potential contribution of geothermal energy to the future mix of renewable generation is not well recognized in many countries. Where geothermal resources are abundantly present and obvious at the surface (typically near plate–tectonic boundaries) there has been rapid progress in geothermal development (growth rates of up to 20% per annum) and this will continue in many countries, especially in the Asian Pacific, Western American and East African regions (representing ∼15% of global population). For the rest of the world, however, the future of geothermal deployment relies on better grid connections to high-temperature resources, deep hot sedimentary aquifers (HSA), or enhanced geothermal system (EGS) technology. HSA and EGS are still in their infancy and operating demonstration plants are only marginally cost-competitive, requiring strong support from subsidies such as feed-in tariffs. The future for geothermal energy in regions of normal subsurface temperature gradient will therefore rely on technological advances in deep drilling and fracture stimulation, and on delivering more cost-competitive heat and power, where it is most needed.