Are Small Modular Reactors The Future Of Nuclear Power?

[Elderberry]

Oilprice By Alex Kimani - Feb 19, 2023

•   Nuclear power is falling back in favor as the push to slash emissions accelerates.

•   Small modular nuclear reactors are affordable and convenient alternatives to traditional plants.

•   Scores of governments, including the U.S. government, have begun incentivizing SMRs by making them more attractive for lenders and utilities.

For decades, many countries have maintained a love-hate relationship with nuclear energy, with the sector regarded as the black sheep of the alternative energy industry thanks to poor public perception, a series of high-profile disasters such as Chernobyl, Fukushima and Three Miles Island as well as massive cost-overruns by nuclear projects. Currently, 440 nuclear reactors operate globally, providing ~10% of the world’s electricity, down from 15 percent at nuclear power’s peak in 1996. In the United States, 93 nuclear reactors generate ~20 percent of the country’s electricity supply.

But Russia’s war in Ukraine and the need for energy security are now forcing a major realignment of energy systems on a global scale, with countries that were formerly strongly opposed to nuclear power such as Germany and Japan now seriously considering incorporating more nuclear energy in their energy mix. Further, the global energy transition is in full swing, and many experts are coming to the realization that the world needs more nuclear power to meet our climate goals. Indeed, according to the International Energy Agency (IEA), the world needs to double the annual rate of nuclear capacity additions in order to reach the 2050 net-zero target. Further, nuclear plants can be paired up with renewable energy projects to act as baseload power thanks to nuclear power possessing the highest capacity factor of any energy source: nuclear plants produce at maximum power more than 93 percent of the time compared to 57 percent for natural gas and 25 percent for solar energy.

Unfortunately, it’s going to be incredibly hard to achieve that milestone thanks to the harsh reality of nuclear power projects. Consider that it not only takes an average of eight years to build a nuclear power plant, but also the mean time between the decision and the commissioning typically ranges from 10 to 19 years. Additionally, major commercial hurdles, primarily the large upfront capital cost and huge cost overruns (nuclear plants have the greatest frequency of cost overruns of all utility-scale power projects), make this an even more onerous endeavor.

Enter small modular nuclear reactors (SMRs).

SMRs are advanced nuclear reactors with power capacities that range from 50-300 MW(e) per unit, compared to 700+ MW(e) per unit for traditional nuclear power reactors. Their biggest attributes are:

•   Modular – this makes it possible for SMR systems and components to be factory-assembled and transported as a unit to a location for installation.

•   Small – SMRs are physically a fraction of the size of a conventional nuclear power reactor.

More: https://oilprice.com/Alternative-Energy/Nuclear-Power/Are-Small-Modular-Reactors-The-Future-Of-Nuclear-Power.html

[DefiantMassRINO]

Dumb question from an ignoramus ...

... what do they do with nuclear reactors from decommissioned nuclear-powered warships?

[Elderberry]

Dumb question from an ignoramus ...

... what do they do with nuclear reactors from decommissioned nuclear-powered warships?

@DefiantMassRINO

Ship-Submarine Recycling Program

https://en.wikipedia.org/wiki/Ship-Submarine_Recycling_Program

Defueling and decommissioning

Before SRP can begin, the vessel's nuclear fuel must be removed, and defueling usually coincides with decommissioning. Until the fuel is removed, the vessel is referred to as "USS Name," but afterward, the "USS" prefix is dropped and it is referred to as "ex-Name." Reusable equipment is removed at the same time as the fuel.[citation needed]

Spent fuel storage

Spent nuclear fuel is shipped by rail to the Naval Reactor Facility in the Idaho National Laboratory (INL), located 42 miles (68 km) northwest of Idaho Falls, Idaho, where it is stored in special canisters.[1]

Hull salvage

At PSNS, the SRP proper begins. The salvage workers cut the submarine into three or four pieces: the aft section, the reactor compartment, the missile compartment if one exists, and the forward section. Missile compartments are dismantled according to the provisions of the Strategic Arms Reductions Treaty.

Until 1991, the forward and aft sections of the submarines were rejoined and placed in floating storage. Various proposals for disposal of those hulls were considered, including sinking them at sea, but none proved economically practical. Some submarines built prior to the 1978 banning of polychlorinated biphenyl products (PCBs) had the chemicals on board, which are considered hazardous materials by the Environmental Protection Agency and United States Coast Guard, requiring their removal. Since then, and to help reduce costs, the remaining submarine sections are recycled, returning reusable materials to production. In the process of submarine recycling, all hazardous and toxic wastes are identified and removed, and reusable equipment is removed and put into inventory. Scrap metals and all other materials are sold to private companies or reused. The overall process is not profitable, but does provide some cost relief.[2] Disposal of submarines by the SRP costs the Navy US$25–50 million per submarine.[citation needed]

Reactor vessel disposal

Once the de-fueled reactor compartment is removed, it is sealed at both ends and shipped by barge and multiple-wheel high-capacity trailers to the Department of Energy's Hanford Nuclear Reservation in Washington state, where they are currently, as of 2016, kept in open dry storage[3] and slated to be eventually buried.[4][5] Russian submarine reactor compartments are stored in similar fashion at Sayda-Guba (Sayda Bay) in northwestern Russia and Chazhma Bay near Vladivostok.[6][7][8] The burial trenches have been evaluated to be secure for at least 600 years before the first pinhole penetration of some lead containment areas of the reactor compartment packages occurs, and several thousand years before leakage becomes possible.[9]

[Kamaji]

Dumb question from an ignoramus ...

... what do they do with nuclear reactors from decommissioned nuclear-powered warships?

Wikipedia article on the decommissioning process for U.S. navy nuclear vessels:  https://en.wikipedia.org/wiki/Ship-Submarine_Recycling_Program

[Elderberry]

The Army's Small Nuclear Reactor Program didn't go over too well.

https://en.wikipedia.org/wiki/Army_Nuclear_Power_Program

The Army Nuclear Power Program (ANPP) was a program of the United States Army to develop small pressurized water and boiling water nuclear power reactors to generate electrical and space-heating energy primarily at remote, relatively inaccessible sites. The ANPP had several accomplishments, but ultimately it was considered to be "a solution in search of a problem." The U.S. Army Engineer Reactors Group managed this program and it was headquartered at Fort Belvoir, Virginia. The program began in 1954 and had effectively terminated by about 1977, with the last class of NPP operators graduating in 1977. Work continued for some time thereafter either for decommissioning of the plants or placing them into SAFSTOR (long term storage and monitoring before decommissioning). The current development of small modular reactors has led to a renewed interest in military applications.[1][2][3]

List of plants

Eight plants were constructed. Due to the requirement for a small physical size, all these reactors other than the MH-1A used highly enriched uranium (HEU). The MH-1A had more space to work with, and more weight-carrying capacity, so this was a low-enrichment reactor; i.e., larger and heavier. The MH-1A was briefly considered for use in Vietnam, but the idea of anything nuclear in Vietnam was quickly rejected by the State Department.[4]

The plants are listed in order of their initial criticality. See the gallery of photos in the next section. Sources for this data include the only known book on the ANPP, by Suid,[6] and a DOE document.[7]

    SM-1: 2 MW electric. Fort Belvoir, Virginia, Initial criticality April 8, 1957 (several months before the Shippingport Reactor) and the first U.S. nuclear power plant to be connected to an electrical grid. Used primarily for training and testing, rather than power generation for Ft. Belvoir. The plant was designed by the American Locomotive Company (renamed ALCO Products, in 1955), and was the first reactor developed under the Army Nuclear Power Program. See the SM-1 image gallery, below. This plant was a tri-service training facility, with both the US Navy and Air Force sending personnel to be trained on shore-based facilities (the Navy had a different stand-alone program for ship-based nuclear power, which is still in operation). The SM-1 and associated training facilities at Ft. Belvoir were the only training facility for shore-based military power plants. The plant cooled its condensers using the waters of the Potomac River. For about the first 10 years of its operation, the SM-1 unknowingly released tritium into the waters of the Chesapeake Bay, until the development of the Packard Tri-Carb detector, which was the first detector system capable of detecting the low-energy beta decay of tritium. The instrumentation in the SM-1 pre-dated the development of solid-state devices and used vacuum tubes.

    SL-1: Boiling water reactor, 200 kW electrical, 400 kW thermal for heating, National Reactor Testing Station, Idaho. Initial criticality August 11, 1958. The SL-1 was designed by the Argonne National Laboratory to gain experience in boiling water reactor operations, develop performance characteristics, train military crews, and test components. Combustion Engineering was awarded a contract by the AEC to operate the SL-1 and in turn employed the Army's military operating crew to continue running the plant. This BWR was specifically designed to power DEW line stations.

    On January 3, 1961, the reactor was being prepared for restart after a shutdown of eleven days over the holidays. Maintenance procedures were in progress which required the main central control rod to be manually withdrawn a few inches to reconnect it to its drive mechanism; at 9:01 p.m. this rod was suddenly withdrawn too far, causing SL-1 to go prompt critical instantly. In four milliseconds, the heat generated by the resulting enormous power surge caused fuel in the core to explosively vaporize. The nuclear fission reaction directly heated the water, flashing a large amount into steam. Melting aluminum reacted with water producing hydrogen gas. The exploding fuel plates, violent metal-water reaction, and expanding water vapor pressed upwards on the water above the core, sending a pressure wave that struck the top of the reactor vessel. The force impinged on the lid of the reactor vessel, causing water and steam to spray from the top of the vessel. This extreme form of water hammer propelled top head shielding, remnants of fuel plates, five loose shield plugs, a nozzle flange, and the entire reactor vessel upwards. A later investigation concluded that the 26,000-pound (12,000 kg) vessel had jumped 9 feet 1 inch (2.77 m) in the air before striking the overhead bridge crane drive shaft. The vessel settled back into its original location, leaving little evidence of this except scattered debris.[8][9] The spray of water and steam knocked two operators onto the floor, killing one and severely injuring another. One of the loose shield plugs on top of the reactor vessel impaled the third man through his groin and exited his shoulder, pinning him to the ceiling.[10][9]The victims were Army Specialists John A. Byrnes (age 27) and Richard Leroy McKinley (age 22), and Navy Seabee Construction Electrician First Class (CE1) Richard C. Legg (age 26).[11]

    It was later established that Byrnes (the reactor operator) had lifted the rod and caused the excursion, Legg (the shift supervisor) was standing on top of the reactor vessel and was impaled and pinned to the ceiling, and McKinley, the trainee who stood nearby, was later found alive by rescuers.[10] All three men succumbed to injuries from physical trauma; the radiation from the nuclear excursion would have given the men no chance of survival.

    This was the only fatal incident at a US nuclear power reactor, which destroyed the reactor. This incident was important in the development of commercial power because future designs prevented the core from going critical with the removal of a single rod.

More at link.

[Kamaji]

The Army's Small Nuclear Reactor Program didn't go over too well.

https://en.wikipedia.org/wiki/Army_Nuclear_Power_Program

More at link.

Most likely because, at the time, it was considered to be a solution in search of a problem.  Now, the problem is appearing, so it may make a lot more sense now than it did back in 1954.

[Elderberry]

Mobile Nuclear Power Reactors Won’t Solve the Army’s Energy Problems

War on the Rocks by Jake Hecla 12/14/2021

Nuclear power is 10 million times more energy dense than fossil fuels and seems to be the ideal solution to securing a robust supply of electricity for the Army free of supply-line vulnerabilities. However, the question is whether or not reactors can truly be made suitable for military use. Are they an energy panacea, or will they prove to be high-value targets capable of crippling entire bases with a single strike? The Army’s nuclear power program is confidently sprinting into uncharted territory in pursuit of a solution to its growing energy needs and has promised to put power on the grid within three years. However, the Army has not fielded a reactor since the 1960s and has made claims of safety and accident tolerance that contradict a half-century of nuclear industry experience.

The Army appears set to credulously accept industry claims of complete safety that are founded in wishful thinking and characterized by willful circumvention of basic design safety principles. Decades of technological advancements in reactor controls and material science will allow these reactors to easily avoid the flaws that precipitated the SL-1 accident, the Army’s last nuclear disaster in 1961. However, over-reliance on a single safety mechanism, the impermeability of the fuel cladding, and refusal to accept the possibility of a release of radioactive material risks an entirely different mode of failure. If deployed without clear-headed understanding of the risks of nuclear power and preparation for significant releases of radioactive material, the Department of Defense risks incurring costs far greater than those of fuel delivery. These risks go far beyond the physical dangers of an attack with radiological consequences. Additionally, the introduction of nuclear power to the battlefield may corrode national security by heightening inter-alliance tensions and familiarizing adversaries with tactics for attacking nuclear infrastructure.

A Mobile Nuclear Power Plant Is Not Worth the Risk

The U.S. Army’s mobile nuclear power plant development program is centered on Project Pele, a truck-and-air-transportable microreactor. Pele promises a 1–5 megawatt electric power (1–5 MW(e)) system weighing less than 40 tons and with exterior dimensions compatible with transport by a C-17 transport aircraft. This reactor is intended to be deployed and started up on extremely short notice at otherwise minimally prepared sites, and is intended for deployment at forward operating bases as well as remote sites. This project has progressed rapidly, garnering $133 million in Fiscal Years 2020–2021, with $28 million distributed each to BWX Technologies and X-energy for the development of designs for mobile, small modular reactor systems in 2020. The design phase of the program will terminate in 2022 with “full power testing feasible by the end of 2023,” an astonishingly short timeline in comparison to commercial reactor systems.

According to its proponents, Project Pele will offer a walk-away-safe, accident-tolerant reactor that uses advanced heat transfer technologies and tri-structural isotropic (more commonly known as TRISO) fuel. To maximize transportability, Project Pele’s reactor designs do not rely on deep burial or concrete castings for protection of the core from kinetic attack but instead use the traditional last line of defense — fuel cladding, a thin protective layer that prevents radioactive products from leaving the fuel — as the barrier to catastrophic radiation release. The total mass limit for the Pele reactor (40 tons, or a bit less than an M1 Abrams) leaves very little room for armor. In response to this, the program manager for Project Pele has presented tri-structural isotropic fuels as nearly invulnerable, stating that the fuel materialis a “real game-changer” and that “even in the case of an attack, [the reactor] is not going to be a significant radiological problem.” In the case of a reactor attack, the program does not “require highly specialized training and equipment for forward area emergency response staff because these locations typically possess only simple emergency response equipment and limited emergency staff.”

Even assuming that the fuel material does not leak fission products under the thermal and mechanical shock of an attack, direct irradiation from reactor fuel fragments will pose a hazard that cannot be mitigated by defense equipment for chemical, biological, radiological, nuclear, and high yield explosives. The gamma dose rate at 50cm from a pea-size tri-structural isotropic fuel fragment with burnup similar to what would be anticipated at the end of a fuel cycle would impart a near-fatal dose in under an hour. Such fragments could easily settle on or lodge in equipment, as seen in the cleanup effort following Chernobyl, rendering it useless. It is conceivable that the exclusion area resulting from a successful reactor strike could force large sections of a base to be evacuated for weeks or months due to the external radiation exposure threat alone.

An attack against a mobile nuclear reactor resulting in the release of fission products could pose a contamination hazard that would render materiel useless, even if fuel fragments are successfully located and removed. Should 1 percent of the fuel particles be damaged in a kinetic attack, tens of kilocuries of volatile fission products would be released. Many of these radioisotopes would react with air, water, and soil to create mobile radioactive contamination that would require topsoil removal; disposal of equipment; and extensive, dose-intensive decontamination using caustic agents and media-blasting. As a point of comparison, decontamination of aircraft used in the response at Chernobyl proved so costly that dozens of military helicopters were decommissioned and left to rust at the accident site even as the Soviet Union pursued a campaign in Afghanistan that was heavily reliant on those aircraft.

Additionally, placing these reactors in combat zones introduces nuclear reactors as valid military targets, which will familiarize adversaries with the tools and tactics needed to attack nuclear infrastructure. Non-state actors may be able to apply their experience attacking military installations to civilian nuclear infrastructure outside of the theater. While reactors deployed in combat zones will be hardened against such attacks, civilian infrastructure cannot be shielded to the same extent. By deploying these systems to the battlefield, the United States may inadvertently help adversaries build a toolkit to export nuclear terror.