Geothermal power's rising importance in today's energy world25 October 2023
Geothermal power is enjoying a resurgence, and attracting growing interest worldwide.
Above: Visualisation of completed surface installations for Geretsried geothermal heat and power facility, Bavaria
A recent significant development was Chubu Electric Power’s decision to participate in the Eavor-Loop(TM) project under development by Alberta (Canada) based start-up Eavor Technologies at Geretsried, Bavaria, Germany. Chubu is taking a 40% stake in Eavor Erdwarme Geretsried GmbH, the operating company for the project, and is already shareholder in Eavor itself.* Eavor holds the remaining 60% of Eavor Erdwarme Geretsried GmbH.
Eavor-Loop(TM) is a “closed-loop” concept for geothermal heat extraction in which a working fluid that is completely isolated from the below ground environment is circulated in subsurface pipework, “collecting heat from the natural geothermal gradient of the Earth via conduction.”
Eavor (pronounced “Ever”), established in 2017, says this approach “represents the world’s first truly scalable form of clean, dispatchable, baseload capable, and flexible heat and power,” and achieves this by “mitigating or eliminating many of the issues that have traditionally hindered geothermal energy.”
Building on Eavor’s experience with a pilot installation in Canada and the Eavor-Deep(TM) deep drilling demonstration in New Mexico, the Geretsried project will see four closed loops installed about 4500 meters underground. It will be the first commercial application of Eavor-Loop(TM) technology.
The heated circulating fluid will be used to provide district heating (64 MWt) and for power generation (8.2 MWe) via an organic Rankine cycle (ORC).
The ORC technology provider is Turboden (part of Mitsubishi Heavy Industries Group).
Another key supplier is pipe maker Vallourec, which previously worked with Eavor on the New Mexico demo project.
Drilling of the first loop at Geretsried started in July 2023, with “partial commercial operations” – completion of first loop – expected in October 2024. Start of full-scale commercial operation, with all four loops completed, is targeted for August 2026.
This project is receiving a 91.6 million euro grant from the EU Innovation Fund.
By participating, Chubu says it plans to acquire experience in and additional knowledge of the geothermal business, with the possibility of future applications of the Eavor-Loop(TM) technology in Japan.
The project also benefits. “Geretsried, with Chubu’s involvement, changes everything,” said John Redfern, Eavor president & CEO.
In June 2023, Eavor completed the first close of their Series B equity round. OMV led the round with a €34 million investment and entered into a commercial agreement with Eavor to pursue large-scale deployment of Eavor-Loop(TM) technology in Europe and beyond.
OMV will be focused initially on the deployment of Eavor-Loop(TM) in Austria, Romania, and Germany.
In March 2023, Eavor announced the signing of a co-operation agreement with Sonoma Clean Power for the development of up to 200 MWe of new geothermal power through the GeoZone initiative in Sonoma and Mendocino Counties, California.
Validating the concept
An Eavor-Loop(TM) entails the connection of two vertical wells with many horizontal multilateral wellbores creating a closed sealed radiator-like heat exchanger system.
Eavor has developed a set of technologies for economically drilling and connecting such a network of loops at thousands of meters depth.
Successful completion of the Eavor-Deep(TM) drilling demonstration project in New Mexico was announced in January 2023.
Combined with the proof of concept demonstrated at the Derek Riddell Eavor-Lite(TM) demonstration facility in Alberta, Canada in 2019, the milestones reached at Eavor-Deep(TM) “validated all the key elements required to construct and operate commercial Eavor-Loops,” says Eavor.
For the Eavor-Lite(TM) Alberta protoype facility the two vertical wells are joined by two horizontal wellbores at 2.4 km depth. There is a connecting pipeline at the surface. See diagram above. The rationale for this configuration, which is not intended to be commercially viable, is to enable the building of a facility that demonstrates all the critical elements of Eavor’s technologies at the lowest cost. The demonstration was “designed to achieve the most efficient path to acceptance and commercialisation of the technology by facility developers and financiers.”
German Chancellor Olaf Scholz (who has visited the Geretsried site) has pledged to greatly increase the use of geothermal energy in Germany, envisaging tenfold expansion by 2030.
Meanwhile, in the UK, ORC technology provider Exergy International and Geothermal Engineering, developer and operator of geothermal plants, have signed a contract for the supply of a 3 MWe gross capacity ORC power plant at the United Downs site, in Cornwall. This represents the first integrated deep geothermal project in the UK. As well as 3 MW of baseload electricity, it will deliver up to 10 MWt of zero- carbon heat to a large housing estate at Langarth Garden Village, a project being developed by Cornwall Council.
Exergy is also working with Pertamina Geothermal Energy on the development of geothermal power plant projects in Indonesia.
In Kenya, Globeleq, described as “the leading independent power company in Africa” and its project partner, the state owned Geothermal Development Company, have broken ground on the 35 MW Menengai geothermal project in Nakuru County.
The $108 million Menengai project is Globeleq’s first geothermal plant. It will operate and maintain the power plant once it achieves commercial operation, targeted for 2025.
Menengai is a greenfield geothermal project and part of the first phase of the wider Menengai complex, which is the second large-scale geothermal field being developed in Kenya after Olkaria. Steam will be supplied to the power plant by GDC under a 25-year project implementation and steam supply agreement. Once the plant is operational, electricity will be sold to Kenya Power, under a power purchase agreement for the same timeframe. Toyota Tsusho Corporation from Japan is the EPC contractor. Fuji Electric is manufacturing and supplying the steam turbine and generator.
The outlook for residential and commercial geothermal projects has also improved in New York, following a vote by the NY legislature to reform geothermal drilling regulations.
The vote was in particular welcomed by the New York Geothermal Energy Organization (NY-GEO), a trade association representing the geothermal heat pump industry in New York State.
Jens Ponikau, president of NY-GEO and co- owner of Buffalo Geothermal said: “To expand the drilling depth for closed loop geothermal bore holes is an important step forward to enable geothermal systems to be installed in dense urban settings.”
The change in current regulations, which treat geothermal systems at depths greater than 500 ft as oil and gas drilling, is expected to open up opportunities for buildings with smaller footprints, and “residential and commercial buildings not able to benefit from the energy bill savings of geothermal heat pumps now can. The ability to drill beyond 500 ft will make geothermal systems more affordable to install and accessible to more New Yorkers.”
European market perspective
Looking at the wider European geothermal market picture, the European Geothermal Energy Council (EGEC) has recently published its assessment of geothermal market developments in 2022, the 12th edition of its annual Geothermal Market Report.
In 2022, there were 142 geothermal power plants in operation with an installed capacity of about 3.5 GWe, achieving an average capacity factor of 79%, EGEC estimates.
In 2022, the expansion of geothermal district heating and cooling capacity persisted and by year end, there were 395 operational systems — an increase of 14 compared with 2021 – as well as more than 300 projects under development.
EGEC expects more than 30 wells to be drilled over the next three to five years for geothermal power plants, and more than 100 wells for heating projects.
2022 witnessed an all-time high in the sales of geothermal heat pump systems, surpassing the previous record set in 2021. With over 141 300 GHP systems installed, sales in 2022 were 17% higher than the previous year. A continuation of this upward trend has already been confirmed in the first quarter of 2023, particularly in Germany and Sweden. More than 2.19 million geothermal heat pumps are in operation in Europe.
EGEC observes that 2023 marks the 110th anniversary of the first-ever geothermal power plant, which entered operation in 1913 in Larderello, Italy. It also notes that the oldest geothermal power plant still in operation is from 1986.
* Other shareholders in Eavor include Vickers Venture Partners, bp ventures, Temasek, OMV, Chevron Technology Ventures, BHP Ventures, BDC Capital, Eversource, Helmerich & Payne, and Precision Drilling