Thorium Fueled Molten Salt Reactors are the Future of Renewable Energy


Or...they could be
Photo by Dan Meyers on Unsplash

The overwhelming majority of Americans want cleaner energy. There is concern over solar and wind power to fulfill the American energy grid's needs fully. Diversifying energy options will help provide baseload power and ensure round the clock clean energy during peak and slow periods. Nuclear is a clean, heavy-hitting form of energy that is often feared due to memorable disasters. However, a safe, cheap nuclear alternative that remains carbon-neutral provides immeasurable power and can eliminate fears of foreign fossil fuel dependence and plutonium weapons worry. That, my friends, is thorium.

The Issue: Uranium

The initial issue is that not all elements are capable of undergoing nuclear fission. Of the uranium ore used to produce energy in nuclear fission reactors, only 3%-5% is U235. U235 is a fissile element, meaning it can be used in fission to create energy. Unfortunately, uranium ore must be enriched to have high enough amounts of U235 for the fission process. The rest of the non-fissile ore eventually transmutes into Plutonium-239. Most people have heard of this stuff: plutonium, during the reaction process, becomes a powerful and sought-after weapon.

We’re just going to skim right over the fact that conventional nuclear reactors create weapons of mass destruction as a byproduct of their energy production. Instead, let’s jump to the fact that this method of using uranium is inefficient—traditional fission results in radioactive waste products with a halflife of up to 10,000 years. Twelve thousand years ago, humans figured out villages could be a thing - ten thousand years ago, we first domesticated cows, just to put that into perspective.

This obviously leads to sequestration issues that must be dealt with for the sake of environmental, societal health, and defense reasons.

The Issue - Conventional Graphite and Light Water Reactors

So let’s talk about light water reactors. Aka LWRs. These babies use water to control and moderate the on-going nuclear fission at the core of a reactor. Basically, graphite fuel rods are heated to heat the water in turn. This produces steam. The steam is used to turn a turbine, which results in power. The water acts as a negative feedback loop in the reactor. Water, in this case, is both a source of energy and safety control. As there is less available water in the reactor, there is more steam. Neutrons slow, and fission slows.

However, solid nuclear fuel is subject to meltdown if not cooled continuously. Most people have heard of at least one meltdown incident: the Fukushima Daiichi disaster, Chernobyl, or Three-Mile Island. User error or even freak natural causes can impede the feedback process and cause catastrophic reactions. This can lead to meltdown even when, as in Fukushima, extraordinary measures are put into place to keep the reactor from overheating. I mean, I don’t blame people for being afraid of that, do you?

Solution A: Thorium

One major upside right off the bat is that most thorium found in the earth is TH232. This is already the most useful version of thorium for use in nuclear reactors. Unlike Uranium-235, thorium is not fissile on its own. Th232 needs neutrons added to split. As such, when the reaction needs to cease, the neutron source needs to be removed. That right there is already it's own failsafe.

The usable thorium eventually decays into U233 - which can actually be fed into its own reactor to generate additional energy. Best part? This way of getting fissile uranium comes without leftover waste from U238. This way of producing fissile uranium produces 1000 to 10,000 times fewer waste products than typical uranium and less radioactivity. Thorium does not produce weapons-ready plutonium but is only radioactive for 500 years compared to uranium’s 10,000.

Yes, any sort of radioactive material left over isn’t ideal - but we can envision what life will look like in 500 years and account for it on some level. Ten thousand? Not so much.

The Solution - Molten Salt Reactors

The other piece of the puzzle here is Molten Salt Reactors (MSRs). MSRs were developed as a product of the Manhattan Project in the 1960s. Essentially when funding dried up, so did the interest. An MSR uses liquid fuel. That is molten salts - like fluoride, instead of solid fuel rods.

When an MSR reaches 700 degrees Celcius, it naturally stabilizes. Due to its very construction, it literally cannot get any hotter. This is because when the salts reach fission stability, they expand into a circulation loop to cool. Since fission cannot occur in this loop, the salts cool further. Thus MSRs are inherently safe and stable for this reason alone. There is little to no possibility of a meltdown.

In the 1960s, a test was done on MSRs that proved that one could run safely and continuously without intervention, even during peak operation - without a control rod or operator. These things can literally run themselves. Unlike conventional reactors, an MSR cannot meltdown by its very nature. MSRs can reduce stockpiled wastes of used nuclear fuel, as old rods can be converted to liquid fuel and recycled.

The final - and perhaps most groundbreaking and innovation-fueling fact is that MSRs use fewer parts. Thus they are smaller. Instead of thinking about multi-story nuclear power plants, think about a small compact nuclear reactor a bit bigger than a human man. What sorts of possibilities does that bring to life? Due to this fact, they are cheaper than conventional reactors and far more easily mass-produced.

So, What Will it Be?

Aside from the obvious radioactive waste, all nuclear is “clean energy.” That is, in terms of CO2 and emissions. Not that we should discount the radioactive part (far from it), but all nuclear is “clean” energy compared to coal and natural gas. The sticking point is just safety.

It is easy to see that combining these two technologies - molten salt reactors and thorium as fuel - results in a nuclear option far safer than any nuclear reactor currently in production in America or elsewhere.

MSRs alone are experiencing a revival of interest in parts of the world like China, Russia, and Japan. Several MSR prototypes are already under research and development globally, including a Molton Salt Fast Neutron Reactor, which uses thorium fuel.

If America does not wish to fall behind in this exciting and important endeavor, policymakers need to do three things. The first is to vote to expand nuclear concerning MSRs rather than other forms of nuclear reactor options. The second is that they need to support public education on these types of reactors and their safety features (we don’t want any terrified masses running about). Finally, policymakers need to allocate funding towards the research and development of both thorium fuel and molten salt reactors to ensure that the United States remains at the forefront of clean and domestic energy.

So to which environmentalist camp do you belong? Are you a nuclear-hater, or all for this technology?
Photo by Johannes Plenio on Unsplash

Some Further Reading, Not Linked Above
Dolan, Thomas James. Molten Salt Reactors and Thorium Energy. 2017. Woodhead Publishing
in Energy. Web.
Heuer, D., Merle-Lucotte, Allibert, Brovchenko, Ghetta, and Rubiolo. "Towards the Thorium Fuel
Cycle with Molten Salt Fast Reactors." Annals of Nuclear Energy 64 (2014): 421-29. Web.
International Atomic Energy Agency. Thorium Fuel Cycle : Potential Benefits and Challenges.
Vienna: International Atomic Energy Agency, 2005. Print. IAEA-TECDOC, 1450.

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I am a travel writer and sustainable lifestyle blogger. As a world traveler, I love giving others tips on budget travel, new cultures, and how to see the planet in a sustainable, ethical way. I also write on being a digital nomad, hiking and outdoor activities, as well as living an adventurous lifestyle.

Santa Fe, NM

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