Nuclear power was headed for something of a resurgence a few years back, but then the 2011 meltdown at Japan's Fukushima reactor happened. Governments and investors around the world got cold feet, but there's now renewed interest in a type of nuclear power that's potentially much safer. You need different fissile material if you're going to change any of that, and now we come to thorium.

Thorium is silvery and tarnishes black when it is exposed to air, forming thorium dioxide; it is moderately hard, malleable, and has a high melting point. Thorium is an electropositive actinide whose chemistry is dominated by the +4 oxidation state; it is quite reactive and can ignite in air when finely divided.The most stable isotope, 232Th, has a half-life of 14.05 billion years, or about the age of the universe;

On Earth, thorium, bismuth, and uranium are the only three radioactive elements that still occur naturally in large quantities as primordial elements.Thorium is estimated to be over three times as abundant as uranium in the Earth's crust, and is chiefly refined from monazite sands as a by-product of extracting rare-earth metals.

Th-232, U-235 and U-238 are primordial nuclides, having existed in their current form for over 4.5 billion years, predating the formation of the Earth; they were forged in the cores of dying stars through the r-process and scattered across the galaxy by supernovas. Their radioactive decay produces about half of the Earth's internal heat.

if you're going to change any of that, and now we come to thorium (atomic number 90). It is estimated that one ton of thorium can produce as much energy as 35 tons of uranium in a liquid fluoride thorium reactor. Conventional reactors utilizes less than one percent of uranium, whereas a well working reprocessing reactor can utilize 99% of its thorium fuel.

Thorium is safer and more efficient to mine than uranium, thus making it more environmentally friendly.The percentage of thorium found in its ore is generally greater than the percentage of uranium found in its ore, so it is more cost-efficient.

Thorium mines has an open pit which does not require ventilation, whereas uranium mines is closed off where the radon level reach potentially dangerous levels. Moreover, as thorium is very abundant in Earth's crust there would be no neccesity to open thorium mines since we already mine and discard it as secondary mining products of other underground valuables such as cobalt, nickel, manganese, copper, etc.

As you may recall, research into the mechanization of nuclear reactions was initially driven not by the desire to make energy, but by the desire to make bombs. The $2-billion Manhattan Project that produced the atomic bomb sparked a worldwide surge in nuclear research, most of it funded by governments embroiled in the Cold War. And here we come to it: Thorium reactors do not produce plutonium, which is what you need to make a nuke.

The history of nuclear power is atrocious. But thorium was an alternative, not a collaborator.

There is up to two orders of magnitude less of nuclear waste in the liquid fluoride thorium reactor, eliminating the need for large scale and long term storage for the waste. This is because the Thorium-Uranium fuel cycle does not irradiate U-238, so it does not produce atoms bigger

than uranium. Furthermore it takes a couple hundred of years for the radioactivity of the waste to drop to safe levels, whereas it take tens of thousands of years for current nuclear waste to drop to safe level. Here's how it works. When Th232 absorbs a neutron it becomes Th233, which is unstable and decays into protactinium-233 and then into U233. That's the same uranium isotope we use in reactors now as a nuclear fuel, the one that is fissile all on its own. Thankfully, it is also relatively long lived, which means at this point in the cycle the irradiated fuel can be unloaded from the reactor and the U233 separated from the remaining thorium. The uranium is then fed into another reactor all on its own, to generate energy.

With uranium reactors it's the U238, turned into U239 by absorbing some of those high-flying neutrons, that produces all the highly radioactive waste products. With thorium, the U233 is isolated and the result is far fewer highly radioactive, long-lived byproducts. Thorium nuclear waste only stays radioactive for 500 years, instead of 10,000, and there is 1,000 to 10,000 times less of it as well.

The International Atomic Energy Agency said molten salt reactors operate at higher temperatures, making them more efficient in generating electricity, while their low operating pressure can reduce the risk of coolant loss, a major accident risk. The liquid fuel acts as as both the source of energy and coolant, so even in a unexpected situation the core cannot overheat. Meltdowns are unthinkable. Research on MSRs is underway at the High Flux Reactor at Petten in the Netherlands, where the Nuclear Research and Consultancy Group (NRG) is collaborating with the European Commission's Joint Research Centre (JRC) in Karlsruhe.

So, should we invest in thorium? Yes. How? There are very few investment vehicles. Most thorium research and development is conducted by national research groups, however you can show your support by posting on social media and spreading awareness.