Enhanced Geothermal Systems Powering Up
Out in the burnt orange tinged dirt, under a fierce sun, next to a dry river bed, Geoff Ward wears a wide-brimmed hat to protect his bald pate from the extreme conditions in Australia’s Channel County – a harsh, arid area once known for cattle grazing. Behind him are a couple flat roof structures with a series of pipes threading in and out of them.
Here, in nearly the geographic center of a continent, but really in the middle of nowhere, Ward and his team at Geodynamics embraced the dust and sweat to find an untapped fuel source that just may change the way countries around the globe think about energy sustainability.
Clean shaven, with deep hazel eyes and a wide, warm smile, Ward, an engineer by trade with a master’s degree in business, who also worked as an investment banker, is no wildcatter hoping for a lucky strike. As the CEO of Geodynamics, who has worked in the energy industry for 20 years, Ward can kick the dirt off his boots and take care of business behind a desk with a geological survey and compass.
But it’s what’s under his boots, beneath the blood red soil, down through 4,000 kilometers of densely packed sediment that gets Ward excited about the future of renewable energy and keeps him and Geodynamics firmly entrenched in the Cooper Basin.
“We have a mantra at Geodynamics, ‘We do what we say we will,’” Ward says. “The alternative energy industry was hurt by evangelicals who described a great promise but took no risks of achieving it. We bring to it not only the commitment but the willingness to deal with the risks of this new technology.”
What they did do was design and construct one of the world’s first viable Enhanced Geothermal Systems power plant in the Cooper Basin of Queensland and South Australia, an area usually reserved for the hundreds of natural gas and oil wells. The 1MWe Habanero Pilot Plant (yes, named after the spicy chili pepper on purpose) was commissioned in April and will finish its test run in September. The company will use the results of that test to put together a proposal for supplying 5-10 megawatts of power to nearby gas producers.
Enhanced Geothermal Systems
It’s a first step that took a 10 year leap of faith and hard work to accomplish. After using exploration records from the gas and oil industry to recognize that the Innamincka granite formation, which is 300 million years old and about 1,200 square kilometers large, produced a high thermal gradient with increases of about 35 degrees centigrade per kilometer, Geodynamics believed they had found a suitable site for EGS.
The concept of Enhanced Geothermal Systems is instead of using geothermal heat associated with volcanic activity and tectonic activity – for example at The Geysers field north of San Francisco, Calif. – extract the heat that's in dry, hard crystalline rock such as granite. This process opens up the prospect of geothermal power being used more broadly and not just in areas near volcanic activity.
The Innamincka granite, which is naturally heated by decaying uranium, thorium, and potassium isotopes, and insulated by densely compacted layers of sediment, topped 240 degrees centigrade at 4,200 meters deep. When they drilled into the granite at the Habanero well and pumped brine into the rock fractures, the fractures became more permeable and the flow increased, which proved it to be a highly productive system.
Geodynamics operates a two-well closed loop system. The heated brine is pumped out of the well and ran through a series of heat exchanges in order to generate steam and drive a turbine. Then the heat is stripped out of the brine and its re-injected back into the fracture system where it percolates through the system becoming reheated.
Long Term Geothermal Energy
The safe, successful, and smooth operation of the 1MWe Habanero Pilot Plant – while proving that the brine loop can be established and controlled with high reliability – has been a huge achievement for the company and for the growth of EGS.
“We think it’s very important,” Ward says. “The Australian government identified geothermal as an energy source that could provide between 10 and 25 percent of the county’s long term secure energy needs.
“We think when our resource in the Cooper Basin is fully exploited it could produce between 2,000 to 6,000 megawatts of power over a 30 year or more period, which is similar to developing a major brown coal area or a major gas area,” Ward says.
From that perspective, EGS is a piece of significant long term energy infrastructure for Australia. The only options for low carbon emission power plants, which are available 365 days a year and 24 hours a day, are geothermal or nuclear.
“Geothermal has a critical role to play in being able to provide a backbone of a long term energy system,” Ward says.
Most studies indicate that when countries see the retirement of the current coal and gas power they are going to need to replace it with some other reliable programmed large scale source. In the U.S., a comprehensive study released by the Massachusetts Institute of Technology titled, “The Future of Geothermal Energy,” examined the potential of EGS as an energy source. The study concluded that by using Enhanced Geothermal Systems technology, at least 100,000 MWe could be produced in the U.S. within 50 years.
According to the MIT study, “Most of the key technical requirements to make EGS work economically over a wide area of the country are in effect, with remaining goals easily within reach.”
Ward could not agree more. “I anticipate we will see more penetration of intermittent renewables like solar and wind, but there still needs to be a core of reliable and programmable base-load power. EGS potentially presents a significant shift in energy security for a number of countries the same way that the ability to access shale gas more cost effectively has changed the energy security in the U.S.”
In Churchill County, Nevada, Ormat Technologies’ Desert Peak 2 EGS project recently received recognition from the U.S. Department of Energy as the nation’s first Enhanced Geothermal Systems plant. Desert Peak is currently providing about 1.7 megawatts of power.
Meanwhile in the Outback
The township of Innamincka, just north of the Habanero EGS plant, has a permanent population of about 15 people. Also to the north is Lake Eyre, the largest lake in Australia, but only when it fills up, which is about once every 5-10 years. But for Ward, there’s beauty in the flat, sun-baked expanse; along with some significant history.
In 1860–61, Robert O'Hara Burke and William John Wills led an expedition of 19 men with the intention of crossing Australia from Melbourne in the south to the Gulf of Carpentaria in the north, a distance of around 3,250 kilometers. They made it up but not all the way back and the historical markers of their graves are only 20 kilometers from the Habanero site.
“The Burke and Wills expedition really is a terrific story of colonial hubris and exploration that ended in tragedy,” Ward says.
It’s a story that Ward and Geodynamics will make sure not to duplicate while continuing their adventure in the middle of it all.
UK must stop blundering into high carbon choices warns CCC
The UK Government must end a year of climate contradictions and stop blundering on high carbon choices, according to the Climate Change Committee as it released 200 policy recommendations in a progress to Parliament update.
While the rigour of the Climate Change Act helped bring COP26 to the UK, it is not enough for Ministers to point to the Glasgow summit and hope that this will carry the day with the public, the Committee warns. Leadership is required, detail on the steps the UK will take in the coming years, clarity on tax changes and public spending commitments, as well as active engagement with people and businesses across the country.
"It it is hard to discern any comprehensive strategy in the climate plans we have seen in the last 12 months. There are gaps and ambiguities. Climate resilience remains a second-order issue, if it is considered at all. We continue to blunder into high-carbon choices. Our Planning system and other fundamental structures have not been recast to meet our legal and international climate commitments," the update states. "Our message to Government is simple: act quickly – be bold and decisive."
The UK’s record to date is strong in parts, but it has fallen behind on adapting to the changing climate and not yet provided a coherent plan to reduce emissions in the critical decade ahead, according to the Committee.
- Statutory framework for climate The UK has a strong climate framework under the Climate Change Act (2008), with legally-binding emissions targets, a process to integrate climate risks into policy, and a central role for independent evidence-based advice and monitoring. This model has inspired similarclimate legislation across the world.
- Emissions targets The UK has adopted ambitious territorial emissions targets aligned to the Paris Agreement: the Sixth Carbon Budget requires an emissions reduction of 63% from 2019 to 2035, on the way to Net Zero by 2050. These are comprehensive targets covering all greenhouse gases and all sectors, including international aviation and shipping.
- Emissions reduction The UK has a leading record in reducing its own emissions: down by 40% from 1990 to 2019, the largest reduction in the G20, while growing the economy (GDP increased by 78% from 1990 to 2019). The rate of reductions since 2012 (of around 20 MtCO2e annually) is comparable to that needed in the future.
- Climate Risk and Adaptation The UK has undertaken three comprehensive assessments of the climate risks it faces, and the Government has published plans for adapting to those risks. There have been some actions in response, notably in tackling flooding and water scarcity, but overall progress in planning and delivering adaptation is not keeping up with increasing risk. The UK is less prepared for the changing climate now than it was when the previous risk assessment was published five years ago.
- Climate finance The UK has been a strong contributor to international climate finance, having recently doubled its commitment to £11.6 billion in aggregate over 2021/22 to 2025/26. This spend is split between support for cutting emissions and support for adaptation, which is important given significant underfunding of adaptation globally. However, recent cuts to the UK’s overseas aid are undermining these commitments.
In a separate comment, it said the Prime Minister’s Ten-Point Plan was an important statement of ambition, but it has yet to be backed with firm policies.
Baroness Brown, Chair of the Adaptation Committee said: “The UK is leading in diagnosis but lagging in policy and action. This cannot be put off further. We cannot deliver Net Zero without serious action on adaptation. We need action now, followed by a National Adaptation Programme that must be more ambitious; more comprehensive; and better focussed on implementation than its predecessors, to improve national resilience to climate change.”
Priority recommendations for 2021 include setting out capacity and usage requirements for Energy from Waste consistent with plans to improve recycling and waste prevention, and issue guidance to align local authority waste contracts and planning policy to these targets; develop (with DIT) the option of applying either border carbon tariffs or minimum standards to imports of selected embedded-emission-intense industrial and agricultural products and fuels; and implement a public engagement programme about national adaptation objectives, acceptable levels of risk, desired resilience standards, how to address inequalities, and responsibilities across society.
Drax Group CEO Will Gardiner said the report is another reminder that if the UK is to meet its ambitious climate targets there is an urgent need to scale up bioenergy with carbon capture and storage (BECCS).
"As the world’s leading generator and supplier of sustainable bioenergy there is no better place to deliver BECCS at scale than at Drax in the UK. We are ready to invest in and deliver this world-leading green technology, which would support clean growth in the north of England, create tens of thousands of jobs and put the UK at the forefront of combatting climate change."
Drax Group is kickstarting the planning process to build a new underground pumped hydro storage power station – more than doubling the electricity generating capacity at its iconic Cruachan facility in Scotland. The 600MW power station will be located inside Ben Cruachan – Argyll’s highest mountain – and increase the site’s total capacity to 1.04GW (click here).
Lockdown measures led to a record decrease in UK emissions in 2020 of 13% from the previous year. The largest falls were in aviation (-60%), shipping (-24%) and surface transport (-18%). While some of this change could persist (e.g. business travellers accounted for 15-25% of UK air passengers before the pandemic), much is already rebounding with HGV and van travel back to pre-pandemic levels, while car use, which at one point was down by two-thirds, only 20% below pre-pandemic levels.