Are Traveling Wave Reactors an Energy Option?
Bill Gates' heart is in the right place on climate: a low carbon emissions energy system is needed. But, when it comes to the traveling wave reactor, his money is not.
A new report from the nonprofit Institute for Energy and Environmental Research (IEER) think tank finds that the "traveling wave reactor" (TWR) concept championed by TerraPower, in which Bill Gates, of Microsoft, is a key investor, may end up a commercial failure.
More than half a dozen countries over more than six decades have already invested $100 billion in an unsuccessful commercialization effort. There has been essentially no demonstrable learning curve: the most recent sodium-cooled demonstration reactors in France and Japan have among the worst reliability records.
The "traveling wave reactor," first conceived in 1958, has been intensively investigated only since about 2006. It is a sodium-cooled "fast" reactor design in which neutrons are not slowed down and the heat created by fission is carried away by liquid sodium, which is used to boil water.
In turn, the steam is used to drive a turbine-generator set to generate electricity. A TWR has never been built. However, the TWR is a type of the sodium-cooled fast reactors that have been pursued with little success over several decades in several countries.
Titled "Traveling Wave Reactor: Sodium-cooled Gold at the End of a Nuclear Rainbow?" the report concludes:
- The sodium-cooled reactor experience does not bode well for TWRs. "Sodium-cooled fast reactors have a checkered history. Some have operated well, while others have done poorly. The most recent commercial demonstration reactors belong in the latter category. The French demonstration reactor, Superphénix, operated at an average capacity factor of less than 7 percent over 11 years before being shut in 1996. The Japanese Monju reactor, commissioned in 1994, and connected to the grid in 1995, had a sodium leak and fire in 1995. It was closed until May 2010, when it was restarted for testing, but suffered another accident in August 2010. It has not been restarted since…."
- Power produced by TWRs would not be affordable or competitive. "Even apart from the poor reliability in many cases, sodium-cooled breeder reactor capital costs have been very variable and have not decreased over time. Fermi I, built in the 1960s, cost about $4,000 per kilowatt, while the Fast Flux Test Facility, operational in 1980, cost over $10,000 per kilowatt. Superphénix cost, commissioned in 1986, about $4,800 per kilowatt, but Monju, commissioned nearly a decade later, cost over $20,000 per kilowatt [all in 1996 dollars].
“Proponents of sodium-cooled reactors, including traveling wave reactors, tend not to focus on how they plan to overcome the problematic parts of the sodium-cooled design history, centered in large part on sodium-related problems, but rather tend to focus on the vast available raw material to produce a large amount of power for the indefinite future. Overall, it is expected that costs of sodium-cooled breeders will be significantly higher than current reactors, despite the fact that about $100 billion have been spent worldwide (2007 dollars) on the attempt to commercialize sodium-cooled breeder reactors, so far without success."
Arjun Makhijani, Ph.D., nuclear engineer and president, Institute for Energy and Environmental Research, and author of the TWR report, said: “By focusing on the uranium resource issue, which is an economic non-problem for the foreseeable future, TWR proponents have lost sight of the practical problems that have prevented commercialization of sodium-cooled breeders despite immense effort and expense.
“Contrary to the claims of proponents, supplying most of the world's electricity with TWRs would create significant proliferation risks, with or without reprocessing, were they to be used as a mainstay of global power generation. Moreover, given the reactor development that remains, it is highly unlikely that such reactors could help significantly alleviate the problem of fossil fuel generation in the next few decades, when it must be solved. TWRs are likely to be economically obsolete before there are commercialized."
Makhijani, who is principal author of the first ever study of energy efficiency potential of the U.S. economy (1971), said he will send Gates his book, “Carbon-Free and Nuclear-Free: A Roadmap for U.S. Energy Policy,” and invite him to debate the path to a low carbon-emissions economy.
Report reviewer M.V. Ramana, Ph.D., Nuclear Futures Laboratory and Program on Science and Global Security, Woodrow Wilson School of Public and International Affairs, Princeton University, said: "Sodium cooled fast neutron reactors have been pursued by several countries around the world. The lesson from the many decades of such pursuit has been that these reactors are expensive, are prone to operational problems and sodium leaks, and are susceptible to severe accidents under some circumstances.
“There is no evidence that the Traveling Wave Reactor will overcome any of these. It is not convincing even on paper.”
- Promised delivery dates for TWRs are wildly unrealistic. “TWR proponents aim to have a demonstration reactor operating by 2022 and the first commercial reactor by the late 2020s. This is an impossible schedule, at least for the United States. The TWR design, like other sodium-cooled reactors, is so different from presently licensed reactors that the Nuclear Regulatory Commission will have to write regulations specifically tailored for them.
“For instance, accident mechanisms in sodium-cooled breeders are different than in light water reactors. It will take years for the Nuclear Regulatory Commission to staff up and acquire the necessary data and expertise to write the rules and do the safety and risk evaluations. As a result, certification and licensing of a demonstration reactor design is likely to take much longer than proponents have allowed for so far. Perhaps that is why TerraPower is reportedly exploring agreements with China and India even though China has little experience with sodium-cooled breeder reactors and India's record so far hardly inspires confidence, having been plagued by leaks and accidents."
- Even if reducing the cost of uranium were possible with TWRs, it would not make nuclear power cheaper. “The main argument that has been made for TWRs is that they can greatly expand the use of the uranium resource without reprocessing. But a paucity of uranium resources is not holding back nuclear power – it is the capital cost of the reactors. Reducing the cost of uranium resources significantly will do almost nothing to alleviate this problem, since the cost of mined uranium in existing power plants is roughly two percent of the overall cost of nuclear power.”
- TWRs may be prone to radioactive leaks and core meltdowns. “… leaks have been a common problem in sodium-cooled breeder programs, including in France, the UK, India, Russia, and Japan. Core meltdown accidents can also occur: two of the U.S. sodium-cooled breeders have had partial core meltdowns. Sodium-cooled reactors have some safety advantages relative to present-day light water reactors, such as operation at low pressure, in contrast to light water reactors. But they also have safety disadvantages, including the potential for the reactor to continue to sustain a chain reaction in the event of coolant loss."
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.