Talk:LFTR

I see one problem and one counter argument:

Thorium seems rarer on Mars than on Earth, as the isotopic measurement done show enriched regions at 1 ppm, while the Earth average is 6 ppm. However this is such early data that it's not all that useful, but it's hard to count on Thorium being readily available. IF we need to extract it from ores at just a few PPM the concentration work may be quite significant.

Regarding solar, it's really a question of the overall mass of the system and the cost of the elements. Solar now depends largely on silica, that is absurdly common, but in a very pure form and specific dopants , that are very difficult to produce. Perovskite solar cells, CH3NH3PbX3, where X is a halogen ion such as iodide, bromide or chloride are developing fast. All these elements are extremely common and are readily available on Mars.

There is no specific reason that a solar society will be energy poor. It's a low density energy source but I often take Quebec as an example: It's a fairly rich society that runs on solar evaporated water, that is also a very low concentration energy source (after all the energy isn't in the dam, it's in the reservoir). It's more constrained in some ways, but again, as I come from Quebec I live in an area where we routinely curtain our activities for entire seasons.

If the Martian storms are at least a bit predictable, farmers will farm around the weather, and not during the night, as they have always done.

As it is, we will see if these reactors get developed on Earth. Let's see if natural gas prices go up and give these reactors a market!

Hi Micheal,

There is no reason to expect that Mars will have less Thorium than Earth, as it formed from the same proto-planetary disk and is refractory, so it would not be depleted near the hot forming sun. Thorium is concentrated in lava flows, and Mars has plenty of those. On Earth, Thorium is about as common in the crust as lead. Even if it is, (for some reason), a bit less common on Mars, we will still gain it in quantity as we mine for Rare Earth Elements. However, I fully expect that when geologists explore Mars, they will find Thorium Ores. A big advantage of nuclear power with Thorium that I had not considered before I read your article, is that it does not need to be enriched like U235.

However this is moot. Let us say that somehow Mars has no Thorium. One starship could deliver a LFTR plus fuel which could power a large city. One starship would provide enough solar cells and batteries to power a village. (Tho if Flow Batteries can be constructed with local materials, you could power two villages.) Asteroids have the solar average of Thorium, so once asteroid mining starts, Mars can be powered by asteroid Thorium (still assuming Mars has zero Thorium).

Thorium is barely radioactive (half life of 14 billion years). Thorium costs ~$20 / kg so a tonne costs $20,000. One starship could be safely filled with Thorium, for under a million dollars, which could then power all of Mars for centuries. There is no reason to be concerned about not finding Thorium, if it really is rare, a few tonnes can be shipped from Earth. (Nuclear power is ~1,000,000 times more energy dense than fossil fuels. TINY amounts of fuel are needed to produce massive amounts of energy.)

Mars gets ~half the solar energy as Earth does. If we terraform it and make the atmosphere thicker, this will cut into the efficiency of solar further. (Tho if we can activate the hydrosphere, hydroelectric dams become a possibility.) I believe that the scientific literate society on Mars will embrace nuclear power, and if they do so, I think LFTR are an ideal choice. However, even if you think that massive solar arrays backed up with massive batteries are feasible, it does not weaken the argument for highly efficient nuclear power. (And LFTR are many times more efficient than light water pressurized reactors designed in the 1950's. The old reactors only burn 0.5% of their fuel, where as LFTRs theoretically, could burn 100% of their fuel.) I expect that when molten salt reactors are built they will be ~100 to 1000 times more profitable than the old fashioned, traditional light water, pressurized nuclear. Unless laws are passed, specifically designed to make them unprofitable, they will be cheaper than natural gas.

If you are interested, I recommend the book, "Molten Salt Reactors & Thorium Energy", edited by Thomas J. Dolan. It talks about the many research groups all over the world which are working on this power source. In Canada, Terrestrial Energy are building Molten Salt Reactors (MSR), they have government approval to build a test reactor. But their first MSR will be U235 based rather than using Thorium.

https://www.terrestrialenergy.com

Warm regards, Rick.