According to a new study, the world’s push for Small Modular Nuclear Reactors to address climate change will generate more radioactive waste than the larger, existing reactors, and its chemical complexity will make it more difficult to manage.
Published in the peer-reviewed journal of the National Academy of Sciences, the study compared designs for three small modular reactors (SMRs) with a standard pressurized-water reactor… It concluded that most SMR designs will “entail a significant net disadvantage for nuclear waste disposal” and will produce wastes that aren’t compatible with existing disposal practices and facilities…
Traditional reactors have been capable of generating up to 1,000 or more megawatts of electricity, and are water-cooled; their spent fuel is highly radioactive and must be isolated from the environment for hundreds of thousands of years. SMRs by definition produce less than 300 megawatts, and would be cooled by novel substances such as molten salt or helium, producing different wastes…The smaller a reactor is, the more neutrons tend to escape the core and affect other components. That will create more radioactivity in the materials used in the reactor vessel which will have to be accounted for as a waste product. The researchers also determined that fuels from some SMRs would likely need processing to make them suitable for underground disposal.
The researchers found the SMRs would produce between double and 30-fold the volumes of waste arising from a typical reactor. They estimated spent fuel would contain higher concentrations of fissile materials than that from traditional reactors. That means the fuel could be at risk of renewed fission chain reactions if stored in high concentrations, meaning it would need to occupy more space underground. Such assertions contradict marketing claims from many SMR vendors…
In 2021, the Union of Concerned Scientists published a report that concluded many proposed SMRs would require new facilities to manage their wastes. It called claims that SMRs could burn existing waste “a misleading oversimplification.” The report found that reactors can consume only a fraction of spent fuel as new fuel – and that requires reprocessing to extract plutonium and other materials that could be used in weapons, thus raising what the organization described as an “unacceptable” risk.
Excerpt from MATTHEW MCCLEARN,The world’s push for small nuclear reactors will exacerbate radioactive waste issues, researchers say, Globe and Mail, June 3, 2022
Four small modular reactors (SMRs) will power the huge Baimskaya copper and gold mining development in the Russian Arctic, according to an agreement signed by Rosatom subsidiary Atomflot…Baimskaya is one of the world’s largest mineral deposits and is very rich in copper and gold. However, development of the remote site in Russia’s eastern Chukotka region demands a complex multi-partner plan involving the Russian government, the regional government and developers…
Nuclear power already plays a role in Baimskaya’s development as early facilities there are powered by the Akademik Lomonosov floating nuclear power plant at Pevek. KAZ Minerals said the plant will supply up to 20 MWe of nuclear power to the mine during its construction phase….Based on the agreement, two additional floating power plants will provided, each with two RITM-200M reactors. The first two should be in operation at Cape Nagloynyn by the beginning of 2027, the third in 2028 and the final one at the start of 2031….
Excerpts from SMRs to power Arctic development, World Nuclear News, Sept. 3, 2021
The U.S. Department of Energy (DOE) announced on Aug. 15, 2019 the launch of the National Reactor Innovation Center (NRIC). The new initiative will assist with the development of advanced nuclear energy technologies by harnessing the world-class capabilities of the DOE national laboratory system. Authorized by the Nuclear Energy Innovation Capabilities Act, NRIC will provide private sector technology developers the necessary support to test and demonstrate their reactor concepts and assess their performance. This will help accelerate the licensing and commercialization of these new nuclear energy systems.
“NRIC will enable the demonstration and deployment of advanced reactors that will define the future of nuclear energy,” said U.S. Energy Secretary Rick Perry. “By bringing industry together with our national labs and university partners, we can enhance our energy independence and position the U.S. as a global leader in advanced nuclear innovation.” NRIC will be led by Idaho National Laboratory and builds upon the successes of DOE’s Gateway for Accelerated Innovation in Nuclear (GAIN) initiative…
The Nuclear Energy Innovation Capabilities Act was signed into law in 2018 by President Donald J. Trump and eliminates some of the financial and technological barriers standing in the way of nuclear innovation. It directs DOE to facilitate the siting of advanced reactor research demonstration facilities through partnerships between DOE and private industry. The House Energy and Water Development committee has allocated $5 million in the FY2020 budget for NRIC, which plans to demonstrate small modular reactor and micro-reactor concepts within the next five years.
Excerpts from DOE, Energy Department Launches New Demonstration Center for Advanced Nuclear Technologies, Press Release, Aug. 15, 2019
Small modular nuclear reactors (SMRs) are relatively small and flexible: they have a power capacity of up to 300 MW(e) and their output can fluctuate in line with demand. This makes them particularly attractive for remote regions with less developed grids, but also for use as a complement to renewables and for non-electric applications of nuclear power. SMRs can be manufactured and then shipped and installed on site, so they are expected to be more affordable to build.
Globally, there are about 50 SMR designs and concepts at different stages of development. Three SMR plants are in advanced stages of construction or commissioning in Argentina, China and Russia, which are all scheduled to start operation between 2019 and 2022…Some SMR designs have features that could reduce the tasks associated with spent fuel management. Power plants based on these designs require less frequent refuelling, every 3 to 7 years, in comparison to between 1 and 2 years for conventional plants, and some are even designed to operate for up to 30 years without refuelling. Nevertheless, even in such cases, there will be some spent fuel left, which will have to be properly managed.
Excerpts from Small Modular Reactors: A Challenge for Spent Fuel Management? IAEA News, Aug. 8, 2019
In January 2019, the Defense Department issued a call for information in support of the aptly titled Project Dilithium. It seeks to develop a tiny, readily transportable, yet virtually indestructible nuclear power reactor for use at forward operating bases, the military facilities that provide logistical and troop support to the front-lines of conflict zones.
To be sure, the type of reactor it is seeking could be a great military asset: all the benefits of nuclear energy with none of the risks. The costly and dangerous process of trucking diesel fuel to bases, sometimes through hostile territory, may eventually be a thing of the past. Unfortunately, the need to store and ship irradiated nuclear fuel in a war zone will introduce different problems. And the odds that a meltdown-proof reactor could be successfully developed any time soon are vanishingly small.
The Defense Department…is seeking a nuclear reactor capable of producing 1 to 10 megawatts of electricity. …The reactor, at a minimum, should be less than 40 tons total weight; small enough to be transported by truck, ship, and aircraft; able to run for at least three years without refueling; and capable of semi-autonomous operation… The reactor should have an “inherently safe design” that ensures “a meltdown is physically impossible in various complete failure scenarios;” cause “no net increase in risk to public safety … by contamination with breach of primary core;” and have “minimized consequences to nearby personnel in case of adversary attack.
An Octrober 2018 report commissioned by the army’s Deputy Chief of Staff admits, quite reasonably, that exposed mobile nuclear plants would “not be expected to survive a direct kinetic attack.” If commanders need to expend significant resources to protect the reactors or their support systems from military strikes, such reactors could become burdens rather than assets. Can one really invent a reactor robust enough to suffer such a strike without causing unacceptable consequences? …If a severe accident or sabotage attack were to induce more extreme conditions than the reactor was designed to withstand, all bets are off. How long would passive airflow keep nuclear fuel safely cool if, say, an adversary threw an insulating blanket over a small reactor? Or if the reactor were buried under a pile of debris?
Moreover, it is hard to imagine that a direct explosive breach of the reactor core would not result in dispersal of some radioactive contamination. An operating nuclear reactor is essentially a can filled with concentrated radioactive material, including some highly volatile radionuclides, under conditions of high pressure and/or temperature. Even a reactor as small as 1 megawatt-electric would contain a large quantity of highly radioactive, long-lived isotopes such as cesium-137—a potential dirty bomb far bigger than the medical radiation sources that have caused much concern among security experts.
At best a release of radioactivity would be a costly disruption, and at worst it would cause immediate harm to personnel, render the base unusable for years, and alienate the host country. For any reactor and fuel design, extensive experimental and analytical work would be needed to understand how much radioactivity could actually escape after an attack and how far it would disperse. This is also true for spent fuel being stored or transported.
The 2018 report describes several existing reactor concepts that it thinks might meet its needs. One is the 2 megawatt-electric “Megapower” reactor being designed by Los Alamos National Laboratory. But a 2017 INL study of the design identified several major safety concerns, including vulnerabilities to seismic and flooding events. The study also found that the reactor lacked sufficient barriers to prevent fission product release in an accident. INL quickly developed two variants of the original Los Alamos design, but a subsequent review found that those shared many of the safety flaws of the original and introduced some new ones.
The other designs are high-temperature gas-cooled reactors that use TRISO (“tristructural isotropic”) fuel, which was originally developed decades ago for use in reactors such as the now-decommissioned Fort St. Vrain plant in Colorado. TRISO fuel consists of small particles of uranium coated with layers of different materials designed to retain most fission products at temperatures up to 1,600 degrees Celsius.
TRISO fuel enthusiasts have long claimed that reactors utilizing it do not need containments because each particle essentially has its own. This would seem to make TRISO an ideal fuel for small, mobile reactors, which can’t be equipped with the large, leak-tight containment structures typical of commercial power reactors. The army report buys into the notion that these “encapsulated” nuclear fuels can “avoid the release of radioactive volatile elements” and prevent contamination of the surrounding area, either during normal operations or accidents.
TRISO fuel’s actual performance has been inconsistent, however, and much is still not known. The Energy Department has been carrying out a program for more than a decade to try to improve TRISO fuel, but final results are not expected for years. In addition, if the fuel temperature rises above 1,600 degrees Celsius, fission product release can rapidly increase, making it vulnerable to incendiary weapons that burn hotter, such as thermite. The Defense Department may have already realized that TRISO fuel is not as miraculous as it first thought.
The RFI also specifies that the reactor should be capable of being transported within seven days after shutdown, presumably with the irradiated nuclear fuel still inside. While this requirement is understandable—if forces need to retreat in a hurry, they would not want to leave the reactor behind—it is unrealistic to expect this could be met while ensuring safety. Typically, spent nuclear fuel is stored for many months to years after discharge from a reactor before regulators allow it to be shipped, to allow for both thermal cooling and decay of short-lived, intensely radioactive fission products. Moving a reactor and its irradiated fuel so soon after shutdown could be a risky business.
Finally, the proliferation risks of these reactors and their fuel is a concern. The original RFI stipulated that the reactor fuel had to be high-assay low-enriched uranium (HALEU), which is uranium enriched to levels above the 5 percent uranium-235 concentration of conventional power reactors, but still below the 20 percent that marks the lower limit for highly enriched uranium (HEU), which is usable in nuclear weapons….If the Defense Department goes forward with Project Dilithium, other nations, including US adversaries, may be prompted to start producing HALEU and building their own military power reactors.
Excerptsf rom Edwin Lyman The Pentagon wants to boldly go where no nuclear reactor has gone before. It won’t work, Feb. 22, 2019
Nuclear is already the largest source of low-carbon energy in the United States and Europe and the second-largest source worldwide (after hydropower). In the September 2018 report of the MIT Energy Initiative, The Future of Nuclear Energy in a Carbon-Constrained World shows that extending the life of the existing fleet of nuclear reactors worldwide is the least costly approach to avoiding an increase of carbon emissions in the power sector. Yet, some countries have prioritized closing nuclear plants, and other countries have policies that undermine the financial viability of their plants. Fortunately, there are signs that this situation is changing. In the United States, Illinois, New Jersey, and New York have taken steps to preserve their nuclear plants as part of a larger decarbonization strategy. In Taiwan, voters rejected a plan to end the use of nuclear energy. In France, decisions on nuclear plant closures must account for the impact on decarbonization commitments. In the United Kingdom, the government’s decarbonization policy entails replacing old nuclear plants with new ones. Strong actions are needed also in Belgium, Japan, South Korea, Spain, and Switzerland, where the existing nuclear fleet is seriously at risk of being phased out.
What about the existing electricity sector in developed countries—can it become fully decarbonized? In the United States, China, and Europe, the most effective and least costly path is a combination of variable renewable energy technologies—those that fluctuate with time of day or season (such as solar or wind energy), and low-carbon dispatchable sources (whose power output to the grid can be controlled on demand). Some options, such as hydropower and geothermal energy, are geographically limited. Other options, such as battery storage, are not affordable at the scale needed to balance variable energy demand through long periods of low wind and sun or through seasonal fluctuations, although that could change in the coming decades.
Nuclear energy is one low-carbon dispatchable option that is virtually unlimited and available now. Excluding nuclear power could double or triple the average cost of electricity for deep decarbonization scenarios because of the enormous overcapacity of solar energy, wind energy, and batteries that would be required to meet demand in the absence of a dispatchable low-carbon energy source. One obstacle is that the cost of new nuclear plants has escalated, especially in the first-of-a-kind units currently being deployed in the United States and Western Europe. This may limit the role of nuclear power in a low-carbon portfolio and raise the cost of deep decarbonization. The good news is that the cost of new nuclear plants can be reduced through…modular construction shifting labor from construction sites to productive factories and shipyards…and seismic isolation to protect the plant against earthquakes, which simplifies the structural design of the plant.
Excerpts from John Parsons, A fresh look at nuclear energy, Science, Jan. 2019
The Barakah nuclear-power plant under construction in Abu Dhabi will never attract the attention that the Burj Khalifa skyscraper in neighbouring Dubai does, but it is an engineering feat nonetheless. It is using three times as much concrete as the world’s tallest building, and six times the amount of steel. Remarkably, its first reactor may start producing energy in the first half of this year—on schedule and (its South Korean developers insist) on budget. That would be a towering achievement.
In much of the world, building a nuclear-power plant looks like a terrible business prospect. Two recent additions to the world’s nuclear fleet, in Argentina and America, took 33 and 44 years to erect. Of 55 plants under construction, the Global Nuclear Power database reckons almost two-thirds are behind schedule . The delays lift costs, and make nuclear less competitive with other sources of electricity, such as gas, coal and renewables.
Not one of the two technologies that were supposed to revolutionise the supply of nuclear energy—the European Pressurised Reactor, or EPR, and the AP1000 from America’s Westinghouse—has yet been installed, despite being conceived early this century. In Finland, France and China, all the EPRs under construction are years behind schedule. The main hope for salvaging their reputation—and the nuclear business of EDF, the French utility that owns the technology—is the Hinkley Point C project in Britain, which by now looks a lot like a Hail Mary pass.
Meanwhile, delays with the Westinghouse AP1000 have caused mayhem at Toshiba, its owner. The Japanese firm may announce write-downs in February of up to $6bn on its American nuclear business. As nuclear assets are probably unsellable, it is flogging parts of its core, microchip business instead.
This month, Oregon-based NuScale Power became the first American firm to apply for certification of a small modular reactor (SMR) design with America’s nuclear regulators.
“Clearly the momentum seems to be shifting away from traditional suppliers,” says William Magwood, director-general of the OECD’s Nuclear Energy Agency. Both small and large reactors are required. In places like America and Europe, where electricity demand is growing slowly, there is rising interest in small, flexible ones. In fast-growing markets like China, large nuclear plants make more economic sense.
If the South Koreans succeed with their first foreign nuclear programme in Abu Dhabi, the reason is likely to be consistency. Nuclear accidents such as Three-Mile Island in 1979 and Chernobyl in 1986 caused a long hiatus in nuclear construction in America and Europe. But South Korea has invested in nuclear power for four decades, using its own technology since the 1990s, says Lee Jong-ho, an executive at Korea Electric Power (KEPCO), which leads the consortium building Barakah. It does not suffer from the skills shortages that bedevil nuclear construction in the West.
KEPCO always works with the same, familiar suppliers and construction firms hailing from Korea Inc. By contrast, both the EPR and AP1000, first-of-a-kind technologies with inevitable teething problems, have suffered from being contracted out to global engineering firms. Also, South Korea and China both keep nuclear building costs low through repetition and standardisation, says the World Nuclear Association (WNA), an industry group. It estimates that South Korean capital costs have remained fairly stable in the past 20 years, while they have almost tripled in France and America.
Excerpts The nuclear options: How to build a nuclear-power plant, Economist, Jan. 28 2017, at 57
Small Modular Reactors (SMRs) are nuclear power plants that are smaller in size (300 MWe or less) than current generation base load plants (1,000 MWe or higher). These smaller, compact designs are factory-fabricated reactors that can be transported by truck or rail to a nuclear power site. SMRs will play an important role in addressing the energy security, economic and climate goals of the U.S. if they can be commercially deployed within the next decade….
Because of their smaller size, they also can use passive safety systems and be built underground to limit the dangers of radioactive leaks. The modular design could allow parts of the plant to be made in a factory to ensure consistent design and cheaper costs.
Tennessee Valley Authority (TVA) is in a joint pilot project with the U.S. Department of Energy to help test the new technology. Dan Stout, senior manager of SMR technology at TVA, said working with DOE to test the new power plant “is part of TVA’s mission,” although he said any final decision will require that the power source is also cost effective. “We’re focused on providing an option that provides reliable, affordable and carbon-free energy, and so we want to pursue this early site permit to give us the option for possibly locating SMRs on the site for 10 to 20 years,” Stout said.