The UN IPCC paper on geothermal energy


Geothermal energy has the potential to provide long-term, secure base-load energy and greenhouse gas (GHG) emissions reductions. 


Accessible geothermal energy from the Earth’s interior supplies heat for direct use and to generate electric energy. The widespread deployment of geothermal energy could play a meaningful role in mitigating climate change.


Overall, geothermal technologies are environmentally advantageous because there is no combustion process emitting carbon dioxide (CO2), with the only direct emissions coming from the underground fluids in the reservoir. 


Geothermal is almost eternal "Hydrothermal, convective systems are typically found in areas of mag-matic intrusions, where temperatures above 1,000°C can occur at less than 10 km depth. Magma typically emits mineralized liquids and gases, which then mix with deeply circulating groundwater. Such systems can last hundreds of thousands of years, and the gradually cooling magmatic heat sources can be replenished periodically with fresh intrusions from a deeper magma chamber. Heat energy is also transferred by conduction, but convection is the most important process in magmatic systems." (IPCC paper page 406)
Go to the IPCC geothermal report
Potential geothermal sites in the Pyrenees

Geothermal power is almost eternal power


The amount of heat within the earth's surface is estimated to contain many times more energy than all the oil and gas resources worldwide. 


Geothermal power therefore offers considerable potential for growth. Increasing deployment and the opening of new markets should drive down the technology’s upfront development costs, further increasing the competitiveness of geothermal power and making it more attractive to investment.


IRENA (The International Renewable Energy Agency) has a technology brief on geothermal power and compares its cost with other sources. This brief is downloadable from the IRENA website.


The levelised cost of electricity (LCOE) of geothermal power plants is about USD 0.04—0.14 per kilowatt-hour.  This is comparable with all fossil fuel power generation costs and with most renewable power sources e.g. solar and wind.


The main barriers to geothermal development are financial, environmental and administrative. The technical problems have been solved.
Go to the IRENA.org website

World Bank article and website on geothermal


Some 40 countries in Africa, East Asia and the Pacific, and Latin America and the Caribbean all have sizeable geothermal resources that can help them meet their energy needs in a reliable and low-cost way.


Geothermal energy could also help curb harmful emissions. The International Energy Agency (IEA) projects that by 2050 geothermal power could amount to 200 GW of installed capacity, avoiding 760 million tons of CO2 emissions annually.


More countries have been opening doors to private developers and are following a model where the public and private sectors share cost and risks. For example, one of the key-components to Turkey’s unparalleled growth in geothermal development has been the de-risking of geothermal fields using public funds.
World Bank paper on mobilizing risk capital for geothermal power World Bank geothermal news

Even the UK has some geothermal potential


There are over 600 existing oil and gas wells on land (as opposed to offshore) in the UK that could be re-purposed for geothermal power generation.
UK geothermal potential

The environmental impact of geothermal overall is comparable to solar


This research paper addresses the environmental impact of geothermal power plants, wells and drilling by studying the Hellisheidi plant in Iceland.
Environmental impact paper

The benign effects of UK geothermal power in reducing carbon emissions


Extracts from the research paper


When completed, the United Downs Deep Geothermal Power project (UDDGP) will be the first geothermal plant ever to be commissioned in the United Kingdom; the project represents a considerable advancement for the energy sector in the country


This article presents a comprehensive and detailed Life Cycle Assessment (LCA) study using site-specific data to quantify the potential environmental impacts of the UDDGP project in particular, and of geothermal energy in the UK in general, in terms of a base case and nine alternative scenarios 


The results allowed us to compare the environmental performance of the UDDGP project, and by extension of the UK geothermal energy, against other energy sources. The comparison highlighted clear trade-offs between environmental categories


Based on our results, geothermal energy should be the third most environmentally benign option after nuclear pressurised water reactors and wind offshore farms, if the ultimate objective is reducing carbon emissions
UK United Downs impact paper

The Future - Perpetual Power - Magma Geothermal


The route to eternal renewable power is to use the heat of the molten magma below the Earth's crust.


The World's first magma geothermal system was created in Iceland.


This paper describes the work and the still challenging technical issues to be addressed before the system can be operational almost anywhere.