Fear of the Unknown Energy
By: Danny Knuth
Nuclear power has been silently powering the United States for the past 60 years. It supplies the US with 20% of its energy and just over half of the total carbon free energy. So why don’t people know that much about it? Why do people fear it? And why should nuclear energy be considered the most important energy source on our way to renewable power sources?
Harnessing nuclear fission is not a new concept. The science of atomic change and nuclear fission was being explored before the turn of the 20th century with the apex of nuclear utilization research being between 1943-1945. When World War II ended, nuclear research shifted to harnessing the power of fission, and by December of 1951, the first electric power from a nuclear reactor started up. From there, commercial use and production of nuclear reactors increased, and so did the energy production. However, by the late 1980s the rapid production of nuclear reactors slowed. Increased concerns for safety, waste disposal, and other environmental factors effectively slowed the nuclear sector. As of today, the United States has nearly 100 operational reactors in 29 states. They are silently producing an immense amount of power for the United States but fear still lingers about their operational safety.
In 1986, the world saw its first major nuclear disaster. Reactor number 4 at the Chernobyl power plant had a complete meltdown. This disaster killed 30 people from the direct aftermath and hundreds more due to acute radiation poisoning. This nuclear meltdown caused a massive reduction in nuclear power progress but was not the nail in the coffin. In March of 2011, a 15-meter tsunami caused by a 9.0 earthquake disabled the power cooling system at the Fukushima nuclear power plant in Japan resulting in the meltdown of three nuclear cores. Following this accident, Germany and Italy shut down their nuclear programs, Switzerland and Spain have restricted any new construction of reactors, and many other countries have called for a halt on their nuclear power plant production. But this downscaling is unnecessary and impulsive.
Fear, mob mentality, and democracy are a dangerous combination. Nuclear programs are shutting down due to a public fear of preventable incidents. For example, the Fukushima power plant was built only 10 meters above sea level. In the century before the disaster there had been 11 seismic events with some producing waves higher than 10 meters. To say the Fukushima plants were under designed is an understatement, but there is a solution to remedy this fear and in some cases ineptitude. The solution is a molten salt reactor.
A molten salt reactor (MSR) is a nuclear reactor that uses liquid fuel instead of soil conventional fuel rods. And it is solving many of the issues that plague a conventional reactor.
The diagram above shows the layout of one variation of molten salt reactors. As shown on the left, the reactor is filled with fuel salt, a combination of dissolved uranium-235 in molten fluoride salts. As the reaction occurs and temperatures rise, fuel is pushed into a heat exchange chamber. That heat is transferred to water and the water evaporates creating steam. That steam then powers a turbine and creates electrical power. The cooled fuel salt is then pumped back into the reactor to start the process again.
What makes the molten salt reactor different from conventional nuclear reactors are the emergency dump tanks.
As shown to the right, there is an emergency plug that is continuously cooled when powered. If the fuel salts become too hot or the facility loses power, like what happened at Fukushima, the fuel is cycled into these tanks where it can cool, and the reaction stops. This makes the facility “walk away” safe. Which means that the facility could be completely left alone and would not have a meltdown.
In addition to the increased safety of the MSR, it is also an extremely efficient reactor. Conventional reactors can only use about 4% percent of the potential energy stored in fuel rods before they corrode and pose a threat. Molten salt reactors can take the fuel pellets within those rods and dissolve them into the fluoride salts. It is estimated that MSR could run for 70 years off the spent fuel rods from conventional reactors. And when it is all said and done MSR produces about 3 kg of waste per year.
The Bottom Line
Nuclear power is an extremely vital role to many countries’ power grid. However, there is a fear associated with it. That fear is based on a very small percentage of outliers that had flaws to begin with. Molten salt reactors have been around since the 1960s and just now are getting their renaissance. Nuclear power provides drastically cleaner power when compared to fossil fuels and has the current infrastructure and knowhow to become a larger player in the energy sector. As of now the renewable energies world is growing, but it is not enough to stop or replace the fossil fuels division. That is why nuclear energy should be the stepping stone, the helping hand to kick start the renewable energies regime.
The History of Nuclear Energy. Washington, D.C.: U.S. Dept. of Energy, 1985.
Serp, Jérôme, Michel Allibert, Ondřej Beneš, Sylvie Delpech, Olga Feynberg, Véronique Ghetta, Daniel Heuer, et al. “The Molten Salt Reactor (MSR) in Generation IV: Overview and Perspectives.” Progress in Nuclear Energy 77 (2014): 308–19. https://doi.org/10.1016/j.pnucene.2014.02.014.
Shimazu, Yoichiro. “Reactor Physics of MSR.” Molten Salt Reactors and Thorium Energy, 2017, 93–109. https://doi.org/10.1016/b978-0-08-101126-3.00004-x.
Photos for the blog post were taken from the Department of Energy