Geothermal power in the United Kingdom

Last updated

The potential for exploiting geothermal energy in the United Kingdom on a commercial basis was initially examined by the Department of Energy in the wake of the 1973 oil crisis. Several regions of the country were identified, but interest in developing them was lost as petroleum prices fell. Although the UK is not actively volcanic, [1] a large heat resource is potentially available via shallow geothermal ground source heat pumps, shallow aquifers and deep saline aquifers in the mesozoic basins of the UK. [2] Geothermal energy is plentiful beneath the UK, although it is not readily accessible currently except in specific locations. [3]

Contents

Geothermal energy in the United Kingdom, though underutilised, has significant potential. [4] [5] The country's geothermal resources could theoretically meet all of its heating demand for the next century. [6] Recent developments, particularly in Cornwall such as the Eden Project and the Langarth Garden Village, include geothermal heating plants and power projects, with plans to generate 12 MW of electricity by 2027. However, challenges such as lack of government support, financial incentives, and a clear regulatory framework hinder broader adoption. [7] With better policy, the UK could establish up to 360 plants by 2050, reducing carbon emissions and providing jobs. [8]

Southampton District Energy Scheme Southampton District Energy Scheme.jpg
Southampton District Energy Scheme

History

Ancient legend credited the early Celtic kings with the discovery of the thermal springs at the Roman Baths in Aquae Sulis (modern city of Bath) which then fell into disrepair during the Dark Ages and were not rediscovered until the 18th century, along with the springs at Buxton in the Peak District.[ citation needed ]

The geothermal potential of the UK was investigated by a program funded by the UK government and the European Commission that ran from 1977 until 1994, [9] and saw a Hot Dry Rock experiment drilled in Carnmenellis granite of Cornwall. The project, which was never intended to produce electricity, was a rock mechanics experiment to research the hydraulic stimulation of fracture networks at temperatures below 100 °C (212 °F). Three wells were drilled to a total vertical depth of 2.6 km (1.6 miles) where the bottom-hole temperature was around 100 °C. In 1994, the Hot Dry Rock project was closed, and research effort was transferred to the European Geothermal Project at Soultz-sous-Forêts. [9]

Geothermal energy development in the UK has been limited, partly due to the lack of high enthalpy resources, but also due to the availability of cheap fossil fuels. [9] However, when comparisons are made to countries in a similar tectonic setting, it is clear that the UK is underutilising this potential resource. The lack of geothermal development has largely been a result of the availability of North Sea natural gas during the 1980s and 1990s. [9]

Interest in the geothermal energy resources of the UK rose again in the 2000s, as a potential way of addressing some of the UK's "energy gap" [ broken anchor ]

Solar (shallow geothermal) energy

There is what may be mistakenly known as geothermal energy at shallow depths but it is technically solar energy; the upper 10 to 15 m (33 to 49 ft) of ground is heated by solar radiation and not (except in rare exceptions) geothermal energy. This acts a heat store and can be exploited in a number of different ways. This heat can be utilised by ground source heat pumps that can substantially reduce heating bills and reduce the associated carbon footprint. The heat from the sun is conducted downwards into the ground. At a depth of about 15 m, ground temperatures are not influenced by seasonal air temperature changes and tend to remain stable all year around at about the mean annual air temperature (9 to 13 °C (48 to 55 °F) in the UK). Hence, the ground at this depth is cooler than the air in summer and warmer than the air in winter. This temperature difference is exploited by ground source heat pumps that are used for heating and/or cooling of homes and office buildings. [10]

Aquifer-based schemes

Groundwater in Permo-Triassic sandstones in the UK has the potential to provide an exploitable geothermal resource at depths of between 1 and 3 km (0.62 and 1.86 miles). Since 1979 the basins of principal interest are East Yorkshire and Lincolnshire, Wessex, Worcester, Cheshire, West Lancashire, Carlisle, and basins in Northern Ireland. In addition, some of these basins are in areas of elevated heat flow, or are overlain by less thermally conductive strata, providing in effect an insulating layer. [10] The following table lists the primary UK Geothermal aquifer resources [10] for areas where the temperature is greater than 40 °C and the transmissivity is greater than 10 Dm, except as indicated:

Aquifer/Basin nameGeologiocal FormationGeothermal
resource
(Exa-joules)
Identified
resource(1)
(Exa-joules)
Depth (m)
East Yorkshire and Lincolnshire Sherwood Sandstone 996.7?
Basal Permian Sands6.70.9(2)?
WessexSherwood Sandstone22.93.2(3)1,700 to 2,200
WorcesterPermo-Triassic (undifferentiated)121.42,500
CheshireSherwood Sandstone16.92.14,000
Permian, including some Triassic27.93.84,000
Northern IrelandSherwood Sandstone35.44.7?
(1) Identified resource calculated assuming an end of process heat rejection temperature of 30 °C; direct use of the fluid, and re-injection of the fluid after use.

(2) Transmissivity ≥5 Dm
(3) In part of area transmissivity 5 to 10 Dm
Note: 1 exa-joule=1018joules

Southampton District Heating Scheme

In the 1980s, the United Kingdom Department of Energy undertook a research and development programme to examine the potential of geothermal aquifers in the UK. However, after some initial success drilling a well in the Wessex Basin in 1981, it was deemed too small to be commercially viable. The project was abandoned by the Department of Energy, but Southampton City Council refused to let the project fall and took the decision to create the UK's first geothermal power scheme. This was undertaken as part of a plan to become a 'self sustaining city' in energy generation, promoted by then leader of the city council Alan Whitehead. The scheme was eventually developed in conjunction with French-owned company COFELY District Energy and the Southampton Geothermal Heating Company was then established. Construction started in 1987 on a well to draw water from the Wessex Basin aquifer at a depth of 1,800 m (5,900 ft) and a temperature of 76 °C (169 °F). [11]

The scheme now heats a number of buildings in the city centre, including the Southampton Civic Centre, the WestQuay shopping centre, Royal South Hants Hospital, Solent University and the Carnival offices; and is part of an enlarged city centre district heating system that includes other combined heating, cooling and power sources. [12] [13] As of 2011 the district heating and cooling scheme provides annually 26 °CGWh of electricity and over 40 °CGWh of heat. [14] Brine from the geothermal well provided 18% of the total district heating mix, with fuel oil (10%) and natural gas (70%) making up the rest. The electricity generated from the scheme is used by Associated British Ports via a private electrical connection to the Port of Southampton, with any surplus electricity sold back to the grid. [12] [ failed verification ]

Stoke-on-Trent

In 2014, Stoke-on-Trent City Council announced plans for a £52 million project to create a district heating network powered by geothermal energy. [15] This will provide heating, in the form of hot water, to local customers. Work started in 2017 and the first customers will be connected in early 2019. [16] [17]

Other

Another area with great potential for geothermal energy is in the North Sea, on the continental shelf where the Earth's crust is thin (less than 10 km [6.2 miles]). The offshore platforms extract hydrocarbons from this region, but each year the output falls by 5% and soon it will be uneconomic to continue using these platforms for fossil fuel extraction. An alternate use could be geothermal power generation. A 1986 work on this was undertaken by Total Energy Conservation and Management Co. Ltd. An overview document was produced called "Single Borehole Geothermal Energy Extraction System for Electrical Power Generation". [18]

Hot rock schemes

Rosemanowes geothermal energy plant 1983 Rosemanowas Geothermal Energy Plant - geograph.org.uk - 1445883.jpg
Rosemanowes geothermal energy plant 1983

The average geothermal gradient in the UK is 26 °C, 47 °F per kilometre (42 °C, 76 °F per mile) depth. [10] There is no deep geothermal power generation in the UK. The granite regions of South West England, the Lake District and Weardale and the Eastern Highlands of Scotland are considered most likely to have the best prospects for power generation. [19] In addition to using geothermally heated aquifers, Hot-Dry-Rock geothermal technology can be used to heat water pumped below ground onto geothermally heated rock. Starting in 1977, trials of the technology were undertaken at Rosemanowes Quarry, near Penryn, Cornwall.

Heat-only projects are generally considered to have the greatest potential in the UK because the resource is more widespread and shallower. This includes the hot aquifers (i.e. subterranean bodies of water) in the North East, Wessex, Cheshire, and Northern Ireland.[ clarification needed ] The UK's only existing geothermal heat-generating station (heat only) is at Southampton, where an 1,800 m (5,900 ft) borehole taps into the edge of the aquifer under Wessex and provides heat to the Southampton District Energy Scheme. The borehole is being refurbished. [19]

In 2008, a planning application was submitted for a hot rocks project on the site of a former cement works at Eastgate, near Stanhope in County Durham. The geothermal plant will heat the Eastgate Renewable Energy Village, the UK's first geothermal energy model village. [20] However this was shelved in 2010. [21]

In 2010 planning permission for a commercial-scale geothermal power plant was granted by Cornwall Council. [22] The plant will be constructed on the United Downs industrial estate near Redruth by Geothermal Engineering. The plant will produce 3 MW of renewable electricity. Drilling commenced at the site in November 2018. [23]

In December 2010, the Eden Project in Cornwall was given permission to build a Hot Rock Geothermal Plant. Drilling was planned to start in 2011, but as of May 2018, funding is still being sought. [24] The plant will be on the north side of the Eden Project, a showcase for environmental projects at Bodelva, near St Austell. It should produce 3-4 MW of electricity for use by Eden with a surplus, enough for about 3,500 houses, going into the National Grid. [25] [26]

Deep geothermal energy in the UK

The Deep Geothermal Challenge Fund of the Department of Energy and Climate Change has provided more than £4.5 million in grants to support the following projects: [19] Power projects

Newcastle Science Central geothermal site Geothermal site, Newcastle upon Tyne, 27 June 2011 (2).jpg
Newcastle Science Central geothermal site

Heat-only projects

United Downs

In early 2013, the government pulled a multimillion-pound grant from Geothermal Engineering Ltd for the £50 million United Downs Deep Geothermal Power project, after the company failed to secure the necessary additional investment to meet the terms of the grant. [27] By 2016, the company had managed to secure £30 million funding for the project from a combination of the European Regional Development Fund, Cornwall Council and private investors, thus financing the UK's first commercial hot rocks power scheme. In 2019, the company had finished drilling the two geothermal wells; the production well to a depth of 5,275 m (17,306 ft) and the injection well to 2,393 m (7,851 ft). The hot water reaches 250 °C (482 °F), and can yield around 60 MW of heat and 10 MW electrical energy. In 2021, the power plant is expected to be commissioned. [28] [29]

Newcastle University

Newcastle University Science Central Borehole Project, at 1,800 m (5,900 ft) is the deepest geothermal well drilled for nearly 30 years. [30] [31] built on the former Tyne Brewery in the city. The temperature profile of 3.9 °C (7.0 °F) per 100 m is higher than that found in Weardale. [32] The project failed as flow rates of hot water from the borehole were not great enough to be exploitable, leaving the development to be heated by conventional sources. [33]

Potential

A report for the Renewable Energy Association prepared by the engineering consultants Sinclair Knight Merz in 2012 identified the following key findings: [34]

Memorandum of understanding with the Icelandic Government

On 30 May 2012, the UK government signed a Memorandum of Understanding with the Icelandic government on a number of energy issues, including supporting the development of deep geothermal energy in the UK. [19]

2023 Renewable Energy Association report

The REA published a new report in 2023 reporting on the nature, current status, future potential, and challenges for the development of geothermal energy infrastructure in the United Kingdom. [6] The report set out the following conclusions:

Current Status

  • Geothermal energy, produced from the Earth's core, is a low-carbon renewable resource for heating, cooling, and power generation. The UK is significantly behind other European countries like France, the Netherlands, and Germany in developing geothermal energy.
  • Only a few deep geothermal projects exist in the UK due to a lack of government support and viable market routes. Key recent developments include the opening of a geothermal heating plant at the Eden Project in Cornwall in 2023, three geothermal power projects clearing the Contracts for Difference auction (set to deliver 12 MW by 2027), and the granting of Green Heat Network Funding for the Langarth Garden Village project.

Future Potential

  • The UK has deep geothermal resources in various regions, including East Yorkshire, Cheshire, Cornwall, and Scotland. It is estimated that geothermal energy could supply the UK's heating needs for the next 100 years.
  • By 2050, the UK could host 360 geothermal plants producing 15,000 GWh of heat annually, enough to heat over 2 million homes. These plants could also generate 400 GWh of electricity, powering about 150,000 homes.
  • Geothermal energy offers many benefits, including decarbonization of heat, energy security, reliable 24/7 availability, job creation, and an opportunity for transitioning oil and gas workers to the green economy.

Challenges

  • Key barriers to geothermal development in the UK include limited financial support and unclear regulation. Currently, there are no coordinated regulatory bodies or licensing systems for geothermal energy.
  • Support mechanisms like better financial incentives, a national geothermal strategy, and streamlined regulations are needed to encourage investment and deployment. The government is encouraged to develop a deep geothermal strategy, including setting national targets and offering incentives such as a Geothermal Development Incentive to support heat projects.

In summary, while the potential for geothermal energy in the UK is considerable, especially for heating, it remains underdeveloped due to policy and regulatory challenges. Addressing these issues could help the country capitalise on its geothermal resources for a greener energy future.

See also

Related Research Articles

<span class="mw-page-title-main">Geothermal power in Iceland</span>

Geothermal power in Iceland refers to the use of geothermal energy in Iceland for electricity generation.

<span class="mw-page-title-main">Geothermal energy</span> Thermal energy generated and stored in the Earth

Geothermal energy is thermal energy extracted from the Earth's crust. It combines energy from the formation of the planet and from radioactive decay. Geothermal energy has been exploited as a source of heat and/or electric power for millennia.

<span class="mw-page-title-main">Energy development</span> Methods bringing energy into production

Energy development is the field of activities focused on obtaining sources of energy from natural resources. These activities include the production of renewable, nuclear, and fossil fuel derived sources of energy, and for the recovery and reuse of energy that would otherwise be wasted. Energy conservation and efficiency measures reduce the demand for energy development, and can have benefits to society with improvements to environmental issues.

<span class="mw-page-title-main">Geothermal heating</span> Use of geothermal energy for heating

Geothermal heating is the direct use of geothermal energy for some heating applications. Humans have taken advantage of geothermal heat this way since the Paleolithic era. Approximately seventy countries made direct use of a total of 270 PJ of geothermal heating in 2004. As of 2007, 28 GW of geothermal heating capacity is installed around the world, satisfying 0.07% of global primary energy consumption. Thermal efficiency is high since no energy conversion is needed, but capacity factors tend to be low since the heat is mostly needed in the winter.

<span class="mw-page-title-main">Eastgate, County Durham</span> Human settlement in England

Eastgate is a village in the civil parish of Stanhope, in County Durham, England. It is situated in Weardale, a few miles west of Stanhope. In the 2001 census Eastgate had a population of 163.

<span class="mw-page-title-main">District heating</span> Centralized heat distribution system

District heating is a system for distributing heat generated in a centralized location through a system of insulated pipes for residential and commercial heating requirements such as space heating and water heating. The heat is often obtained from a cogeneration plant burning fossil fuels or biomass, but heat-only boiler stations, geothermal heating, heat pumps and central solar heating are also used, as well as heat waste from factories and nuclear power electricity generation. District heating plants can provide higher efficiencies and better pollution control than localized boilers. According to some research, district heating with combined heat and power (CHPDH) is the cheapest method of cutting carbon emissions, and has one of the lowest carbon footprints of all fossil generation plants.

<span class="mw-page-title-main">Geothermal gradient</span> Rate of temperature increase with depth in Earths interior

Geothermal gradient is the rate of change in temperature with respect to increasing depth in Earth's interior. As a general rule, the crust temperature rises with depth due to the heat flow from the much hotter mantle; away from tectonic plate boundaries, temperature rises in about 25–30 °C/km (72–87 °F/mi) of depth near the surface in the continental crust. However, in some cases the temperature may drop with increasing depth, especially near the surface, a phenomenon known as inverse or negative geothermal gradient. The effects of weather, the Sun, and season only reach a depth of roughly 10–20 m (33–66 ft).

Renewable heat is an application of renewable energy referring to the generation of heat from renewable sources; for example, feeding radiators with water warmed by focused solar radiation rather than by a fossil fuel boiler. Renewable heat technologies include renewable biofuels, solar heating, geothermal heating, heat pumps and heat exchangers. Insulation is almost always an important factor in how renewable heating is implemented.

<span class="mw-page-title-main">Energy recovery</span>

Energy recovery includes any technique or method of minimizing the input of energy to an overall system by the exchange of energy from one sub-system of the overall system with another. The energy can be in any form in either subsystem, but most energy recovery systems exchange thermal energy in either sensible or latent form.

<span class="mw-page-title-main">Ground source heat pump</span> System to transfer heat to/from the ground

A ground source heat pump is a heating/cooling system for buildings that use a type of heat pump to transfer heat to or from the ground, taking advantage of the relative constancy of temperatures of the earth through the seasons. Ground-source heat pumps (GSHPs) – or geothermal heat pumps (GHP), as they are commonly termed in North America – are among the most energy-efficient technologies for providing HVAC and water heating, using far less energy than can be achieved by burning a fuel in a boiler/furnace or by use of resistive electric heaters.

<span class="mw-page-title-main">Rosemanowes Quarry</span> British granite quarry

Rosemanowes Quarry, near Penryn, Cornwall, England, was a granite quarry and the site of an early experiment in extracting geothermal energy from the earth using hot dry rock (HDR) technology.

<span class="mw-page-title-main">Geothermal power in Australia</span> Overview of geothermal power in Australia

Geothermal power in Australia was at one time hoped to provide cost effect, renewable power for Australia. There are locations that have been shown to contain hot granites at depth which hold good potential for development of geothermal energy. Exploratory geothermal wells have been drilled to test for the presence of high temperature geothermal reservoir rocks and such hot granites were detected. However, all these projects have since been abandoned. A small geothermal plant in Queensland experienced problems during commissioning and as at May 2022, remains idle.

<span class="mw-page-title-main">Nesjavellir Geothermal Power Station</span>

The Nesjavellir Geothermal Power Station is the second-largest geothermal power station in Iceland. The facility is located 177 m (581 ft) above sea level in the southwestern part of the country, near Þingvellir National Park and the Hengill mountain range, about 30 km east of central Reykjavík. The power station is owned and operated by ON Power.

<span class="mw-page-title-main">Renewable energy in the United Kingdom</span>

Renewable energy in the United Kingdom contributes to production for electricity, heat, and transport.

<span class="mw-page-title-main">Enhanced geothermal system</span> Type of electricity generation system

An enhanced geothermal system (EGS) generates geothermal electricity without natural convective hydrothermal resources. Traditionally, geothermal power systems operated only where naturally occurring heat, water, and rock permeability are sufficient to allow energy extraction. However, most geothermal energy within reach of conventional techniques is in dry and impermeable rock. EGS technologies expand the availability of geothermal resources through stimulation methods, such as 'hydraulic stimulation'.

<span class="mw-page-title-main">Geothermal power</span> Power generated by geothermal energy

Geothermal power is electrical power generated from geothermal energy. Technologies in use include dry steam power stations, flash steam power stations and binary cycle power stations. Geothermal electricity generation is currently used in 26 countries, while geothermal heating is in use in 70 countries.

Geothermal energy is the second most used form of renewable energy in Russia but represents less than 1% of the total energy production. The first geothermal power plant in Russia, which was the first Binary cycle power station in the world, was built at Pauzhetka, Kamchatka, in 1966, with a capacity of 5 MW. The total geothermal installed capacity is 81.9 MW, with 50 MW coming from a plant at Verkhne-Mutnovsky.Two other plants were built on the Kamchatka Peninsula in 1999 and 2002. Two smaller additional plants were installed on the islands of Kunashir and Iturup in 2007. Most geothermal resources are currently used for heating settlements in the North Caucasus and Kamchatka. Half of the geothermal production is used to heat homes and industrial buildings, one third is used to heat greenhouses and 13% is used for industrial processes.

The Eastgate Renewable Energy Village is a multimillion-pound project planned for the village of Eastgate in Weardale, County Durham. The plan is to showcase five different forms of renewable energy and create a complex that includes a hotel, spa, cable car ride, 65 new homes, a cafe, viewing platforms, bird watching centre and connection with the Weardale Railway.

United Downs Deep Geothermal Power is the United Kingdom's first geothermal electricity project. It is situated near Redruth in Cornwall, England. It is owned and operated by Geothermal Engineering (GEL), a private UK company. The drilling site is on the United Downs industrial estate, chosen for its geology, existing grid connection, proximity to access roads and limited impact on local communities. Energy is extracted by cycling water through a naturally hot reservoir and using the heated water to drive a turbine to produce electricity and for direct heating. The company plans to begin delivering electricity and heat in 2024. A lithium resource was discovered in the well.

<span class="mw-page-title-main">Southampton District Energy Scheme</span> District heating and cooling system in England

The Southampton District Energy Scheme is a district heating and cooling system in Southampton, United Kingdom. The system is owned and operated by ENGIE.

References

  1. "Geothermal energy — what is it?". British Geological Survey. Retrieved 1 May 2013.
  2. Busby, Jon. "Deep Geothermal energy and groundwater in the UK" (PDF). British Geological Survey. Retrieved 1 May 2013.
  3. "Research Atlas: RENEWABLE ENERGY SOURCES - Geothermal Energy". UK Energy Research Centre. Retrieved 23 June 2013.
  4. Ambrose, Jillian (2 June 2023). "Network of geothermal power stations 'could help level up UK'". The Guardian. ISSN   0261-3077 . Retrieved 15 October 2024.
  5. Whitlock, Robin (12 September 2024). "UK Day One releases report on the case for geothermal energy". Renewable Energy Magazine. Retrieved 15 October 2024.
  6. 1 2 "Policy Briefing: Deep Geothermal" (PDF). Association for Renewable Energy and Clean Technology . 2 July 2024. Retrieved 15 October 2024.
  7. "Future of the subsurface: geothermal energy generation in the UK (annex)". Government of the United Kingdom . 3 October 2024. Retrieved 15 October 2024.
  8. Cariaga, Carlo (2 June 2023). "UK MP publishes report on UK's deep geothermal potential". Think Geoenergy. Retrieved 15 October 2024.
  9. 1 2 3 4 Busby, Jon (25–29 April 2010). "Geothermal Prospects in the United Kingdom" (PDF). Proceedings World Geothermal Congress. Bali, Indonesia. Retrieved 1 May 2013.
  10. 1 2 3 4 "Evaluation of the Permo-Triassic Sandstones of the UK as Geothermal Aquifers; by D.J. Allen, I.N. Gale & M. Price; British Geological Survey; 1985" (PDF). Retrieved 12 February 2011.
  11. "Geothermal Energy in the United Kingdom - Southampton District heating scheme" (PDF). Retrieved 12 February 2011.
  12. 1 2 "Southampton City Council webpage describing the scheme". Archived from the original on 17 December 2013. Retrieved 21 December 2013.
  13. "EU Case Study: Geothermal District Heating Project, Southampton". www.managenergy.net. Retrieved 3 December 2022.
  14. "District Energy Scheme 2011_tcm46-299457" (PDF). www.southampton.gov.uk. Archived from the original (PDF) on 17 December 2013. Retrieved 11 January 2022.
  15. "Could a 350 million-year-old volcano heat Stoke-on-Trent?", The Sentinel, 25 September 2014
  16. "Stoke-on-Trent preparing work on geothermal district heating network". www.thinkgeoenergy.com. 4 October 2017.
  17. "Experts to be paid more than £50 MILLION to develop Stoke-on-Trent's 'heat network'". www.stokesentinel.co.uk. 31 October 2018.
  18. Single Borehole Geothermal Energy Extraction System for Electrical Power Generation
  19. 1 2 3 4 "Increasing the use of low-carbon technologies: Geothermal energy". gov.uk. Retrieved 1 May 2013.
  20. 'Hot rocks' found at cement plant
  21. "£2m spent on Eastgate Renewable Energy Village, at Stanhope" . Retrieved 27 November 2018.
  22. "'Hot rocks' geothermal energy plant promises a UK first for Cornwall". Western Morning News . 17 August 2010. Retrieved 21 August 2015.[ permanent dead link ]
  23. "Drilling starts at Cornish geothermal electricity plant" . Retrieved 27 November 2018.
  24. "Geothermal power project at Eden Project in Cornwall seeking local funding | ThinkGeoEnergy - Geothermal Energy News". 2 May 2018.
  25. "Eden Project geothermal plant plans to go ahead". BBC News. 18 December 2010.
  26. "Eden Deep Geothermal Energy Project" . Retrieved 4 June 2012.
  27. Shankleman, Jessica (8 April 2013). "Under pressure - UK deep geothermal industry faces uncertain future". Business Green. Retrieved 1 May 2013.
  28. Corbley, Andy (8 January 2021). "UK Debuts Geothermal Plant Using Heat From the Earth to Power 10,000 Homes". Good News Network. Retrieved 12 January 2021.
  29. "United Downs Deep Geothermal Power Project". Archived from the original on 8 March 2022. Retrieved 12 January 2021.
  30. "Science Central Borehole Project". Newcastle Institute for Research on Sustainability. Archived from the original on 1 April 2013. Retrieved 1 May 2013.
  31. "BritGeothermal". British Geological Survey. Retrieved 1 May 2013.
  32. "Hotter than hoped!". Prof. Paul Younger Blog. Archived from the original on 15 April 2012. Retrieved 1 May 2013.
  33. Proctor, Kate (28 November 2014). "Giant 2km borehole project fails to bring hot water to Newcastle businesses". chroniclelive. Retrieved 29 October 2015.
  34. "Deep geothermal resource has potential to produce up to 20% of UK electricity and heat for millions". Renewable Energy Association. Retrieved 1 May 2013.[ dead link ]