Geothermal energy

Geothermal energy can provide heating, cooling and base-load power generation from high-temperature hydrothermal resources, deep aquifer systems with low and medium temperatures, and hot rock resources.

Geothermal heat is primarily used for bathing, swimming and space heating. Use in agriculture, especially for heating greenhouses, is significant in some countries. For example, in Turkey agriculture accounts for 30% of geothermal direct use. Geothermal heat uses are often small-scale and two countries (China and Turkey) account for almost 80% of global geothermal heat use.

	Geothermal heat
Turkey	79.1
Rest of the world	37.1
United States	11.3
New Zealand	7.3
Japan	7.2
Italy	4.8
Iceland	3.4
China	207.3
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Source: IEA World Energy Statistics and Balances 2017

Over the next five years, the biggest growth is expected in China, where geothermal district heating is expanding rapidly in a number of Northern cities to help tackle air pollution problems. In Europe, the use of geothermal heat in district heating is also growing, with the main markets in France, Netherlands, Germany, and Hungary.

Geothermal power plants are particularly common in countries that have high-termperature geothermal resources. In 2015, global geothermal power generation stood at an estimated 82 TWh, while the cumulative capacity reached over 13 GW. Global geothermal power capacity is expected to rise to almost 17 GW by 2021, with the biggest capacity additions expected in Indonesia, Turkey, the Philippines and Mexico. 

Technology Roadmaps

The IEA has developed and regularly updates a series of global, low-carbon energy technology roadmaps which identify priority actions for governments, industry, financial partners and civil society that will advance technology development and uptake to achieve international climate change goals.

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Technology Roadmap: Geothermal Heat and Power

Published: 14 June 2011

The technology roadmap for Geothermal Heat and Power offers a strategic plan to maximise deployment of these energy resources by 2050. It projects that 1,400 TWh of electricity per year could come from geothermal power by 2050, up from 67 TWh at present.

Additionally, geothermal heat (not including ground-source heat pump technology) could contribute 5.8 EJ (1,600 TWh) annually by 2050. In order to reach these targets, policy makers, local authorities and utilities need to be more aware of the variety of geothermal resources available and of their possible applications. This roadmap describes the technological, economic and non-economic barriers facing geothermal deployment, and the steps stakeholders must take to overcome them.

Technology Collaboration Programmes (TCPs)

Geothermal TCP

The goal of the IEA TCP on Geothermal is to provide a framework for international co-operation on R&D. Activities include information sharing; developing best practice on the use of technologies and techniques; exploration, development and utilisation of geothermal; and producing and disseminating authoritative analysis and databases. There are currently 15 Contracting Parties, including Iceland and Mexico, as well as five Sponsors.

Learn more about the Geothermal TCP >

About Technology Collaboration Programmes

The breadth and coverage of analytical expertise in the IEA Technology Collaboration Programmes (TCPs) are unique assets that underpin IEA efforts to support innovation for energy security, economic growth and environmental protection. The 38 TCPs operating today involve about 6 000 experts from government, industry and research organisations in more than 50 countries.

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