Part 1 of 2 Parts
Dr. Sola Talabi is an adjunct assistant professor of nuclear engineering at the Swanson School of Engineering at the University of Pittsburgh. He is also a senior consultant at Pittsburgh Technical, an advisory firm that provides risk management services to the nuclear energy industry. Talabi is an expert in advanced small modular reactors which are mini-nuclear plants ranging in size from tens of megawatts to a maximum of three hundred megawatts.
SMRs generate electricity through nuclear fission. In the core of an SMR, neutrons collided with fuel atoms (usually uranium) and cause them to break apart. As the atoms fragment, they release more neutrons which split more atoms in a sustained chain reaction. They also release energy. The coolant heated by the nuclear fission then passes through a heat exchanger. This produces steam that drives an electrical turbine and produces usable energy.
Dr. Talabi claims that SMRs offer a viable, environmentally-friendly alternative to fossil fuels. They can help satisfy the world’s energy demands while slashing carbon emissions and air pollutants. He told an interviewer that he thinks nuclear power has the ability to solve [the world’s two biggest problems:] global energy poverty and global warming. Nuclear power can uniquely address those issues.
SMRs have not yet penetrated the civilian energy sector. However, they have been powering naval warships and submarines for almost seventy years. U.S. naval nuclear reactors have logged more than five thousand four hundred reactor years. They have propelled vessels more than one hundred and thirty million miles without a single radiological incident or radiation-related fatality. (This is not accurate, see IAEA report) Their sterling safety record allows the U.S. Navy to operate its reactors even in Japan. Japan has a strong anti-nuclear movement born by the nuclear attacks at Hiroshima and Nagasaki and exacerbated by the nuclear disaster at Fukushima.
Despite the success of the Navy SMRs, they have failed to catch on in the U.S. civilian energy sector. In fact, nuclear power provides only about twenty percent of the nation’s energy. All of this energy comes from aging large-scale reactors. Major nuclear disasters including Three Mile Island, Chernobyl, and Fukushima have eroded public support. Even if the nuclear industry could overcome the public relations issues, it still faces various financial and supply chain problems. Dr. Talabi insists that all these problems can be solved or minimized by just scaling down the reactor design.
Dr. Talabi claims that SMRs are far safer than current large scale power reactors. The worst-case scenarios for traditional nuclear power plants are a loss of coolant or loss for flow accidents in which a reactor loses its ability to remove the heat produced by the fuel. In such a case, the nuclear chain reaction spikes and causes the core to melt down. At Three Mile Island, a stuck open relief valve affected the reactor’s pressurization system. At Fukushima, when electrical power to the reactor’s coolant pumps failed, the nuclear fuel rods in the cooling pool overheated, burst into flame, and a meltdown occurred.
Considering SMRs, they take advantage of advanced designs to eliminate the possibility of such accidents. Circulation through the reactor core is accomplished by thermal convection (hot water rises and cold water sinks). A SMR reactor can remove heat generated by its fuel even if electrical power is lost. Next-generation SMR’s are also designed such that they don’t require a pressurizing system like the one that failed at Three Mile Island.
Please read Part 2 next