Energy Content of Thorium


When a LFTR (Liquid Fluoride Thorium Reactor) is used to extract energy from thorium, we could effectively “burn rocks” for energy.

Imagine a cube, perhaps roughly the size of a small car.  In order to see the tiny amount of thorium that would be contained within the average dirt pile, we need to zoom in.

Thorium is only ~0.001% in an average pile of dirt, but it packs in so much energy, that – using LFTR, it contains the equivalent energy content of 30 times the amount of crude oil, compared to the size of the original dirt cube!

Thorium Energy Content Merged Final

Click here if you want to see the math in detail for a cubic meter of dirt.


About LFTR – Liquid Flouride Thorium Reactors


You wouldn’t use a 20 year old cellphone, so why are we using 20+ year old nuclear technology?  The curious reason we are, is because it works, but we could be doing so much better.

Here is the short overview on LFTR and Thorium (the fuel of the future):



– Element 90, found as Thorium 232 in nature, is 4 times more common than Uranium and about 200-400x more common than U-235, the fuel we burn in Light Water Reactors (LWRs) in the US and much of the world.  That’s just the start…

– Thorium is naturally radioactive like uranium, and has a half-life equal to the age of the universe (about 15 billion years) so it will be with us for a long time

– It is found in large quantities in “Rare Earth” mines, which are rare in the US because they dig up Thorium.  Thorium is (weakly) radioactive, and US law requires it be treated as a radioactive waste and buried.  Too much Thorium in a rare earth mine makes it unprofitable, but it is these rare earth mines that bring up the high technology metals we need in society today, such as Neodymium for magnets (think generators and motors).

– A LWR (Light Water Reactor) in the US burns about 0.5%-5% of the fuel put in it, the remaining is disposed of as unburned fuel as part of the radioactive waste.  A LFTR on the other hand, running from Thorium could burn 100% of the fuel

– Because it can all be consumed, if you held a marble a little over an inch across (~3 cm) made of Thorium, it could power your entire (western world) needs for your entire life. (more:

– The “waste” products are far less than that of the Light Water Reactor technology used today.  Also, the amount of mining is far less – and a natural result of a rare earth mine (see above).  (more: and

– The byproducts of a LFTR are radioactive, but contain few “transuranic” elements – which would be radioactive for a very long time.  Instead, much of the “waste” could be recycled into useful products after a month or a few years of cooling off, and by about 100 years, much of the radioactivity is gone.

– There is less risk of proliferation with LFTR (Thorium) fuel, since Thorium doesn’t fission in of itself, and stolen active LFTR fuel would contain U232 (a natural byproduct of the LFTR process, not required to be added).  U232 is very radioactive and would damage electronics and irradiate the people stealing it, and make any stolen material easy to find.


LFTR – Liquid Fueled Thorium Reactor  (A molten-salt reactor using thorium)

– A LFTR is a different kind of reactor.  It was invented during the 1950s and 1960s in Oak Ridge Labs, but was quickly abandoned since the nuclear reactions were found to be not good for bomb-making. (more:

– Since the focus was on bombs and Uranium originally, the infrastructure of LWRs (light water reactors) quickly grew and stabilized, ignoring Thorium technologies such as LFTR (more: – hear the Nixon tape – very damning evidence, and a real shame).

– This kind of reactor can’t “melt down” as it is already liquid.  It runs in the 700°C [1300 °F] range giving far superior thermodynamic efficiency.  High pressure is nowhere near the core, since a hot salt loop transfers the heat to the generators.

– The reactor is designed with a “salt plug” in its base, cooled by a fan.  If power is ever lost, the system fan would shut down (due to lost power), and the plug melts, draining the fuel into a storage container where fission stops.  The fuel would also cool and solidify.  If there were ever a breach in the reactor, material would drain into the same tank.  Even if the tank broke, the fuel would simply solidify on the floor.  Safety can be done completely passively, no worries about hoping systems will be online when needed.   (more:

– The reaction has a natural “negative feedback”, which means that if demand for power grows, the reactor will run faster, but if it falls, it will reduce its output.  It also will run slower as it gets too hot, so more heat does not make the reaction go out of control, it actually slows the reaction (due to expansion making fission less likely).

– The fuel is cheap (see Thorium above), and since there is no high pressure, huge thick walls and buildings are not necessary.  This lowers the space and cost requirements of a building.

– Any nuclear fuel generates Xenon gas while in a reactor.  This gas slows reactions and in the case of LWRs and other solid fueled reactors that we use today, it cracks and damages the fuel pellets.  Since LFTRs are liquid, it simply bubbles out of solution.  It can also be collected, and in a few months is no longer radioactive and can be sold.  This is also one reason the fuel in our current LWRs is only 0.5%-5% consumed, because if it were to be left in longer, the expansion from this would damage the fuel tubes inside of the reactor.

– LFTRs can make isotopes of materials we desperately need.  Mo-99 is needed by hospitals for radiation treatments, Pu238 is needed by NASA for space missions to the outer reaches of the solar system, and Bi213 for new targeted (Leukemia and Pancreas) cancer treatments. (more:

– LFTRs can also burn radioactive “waste” we are currently storing, made from the LWR units of today.  We could actually reduce our radioactive waste using LFTRs and other Molten-Salt Reactors (MSRs) (more:

– China is already working on LFTR technology and stockpiling Thorium.  India is working on Thorium for solid fueled reactors, but will probably move to LFTR as a natural part of that research. (more:


Did you know?

– A typical coal burning plant emits far more radioactivity into the air than any nuclear plant.  Nuclear plants keep their fuels inside the building, but the smoke from coal contains all manner of poisonous materials (mercury, cadmium, etc) and several naturally radioactive ones such as Uranium and Thorium.  These materials are fairly safe as rocks, but as a breathable dust, not so much.

– Nuclear power is over 1,000,000 times more energy dense than burning fossil fuels.  The comparison is nuclear energy to that of a carbon-hydrogen bond. (more:–D2Es – See a visit to Arizona’s Palo Verde Energy Education Center outdoor exhibits)

– US current needs for energy burn a rail car of coal about every 1-3 seconds.  That’s about 100 tons per rail car.

– There have been far more deaths from coal mining than all nuclear power accidents combined. (more: – graphs at 2m:40s)




Wind Power Capacity

You often see articles like “100% of new capacity built in location X this year was renewable“, but what does that mean?

Let’s explore the German wind power build-out as an example.  If you look at this graph from 2014, you will notice the actual capacity that the turbines are rated for is the upper line.  The lower, small series of spikes is the actual power produced by the wind turbines.  It occurs at effectively random times and so does not follow demand, and it is roughly 20% of the theoretical maximum total of the turbines.

2014 German wind output vs capacity

This means that if you build a 10 MW wind turbine, over the year you should get an average of 2 MW out of it – and, as I mentioned, randomly.  Power grids can handle a little of this kind of power, but there are serious limits what you can put on the grid.  Ignoring that though, it means you need about 1500, 10 MW turbines (capacity would be 15000 MW, actual output 3000 MW) to equal a single good size nuclear plant in output.  However, having the power reliably produced from the nuclear plant means that it is predictable and useful.

Predictable and useful means you can reliably displace other sources with it.  We burn a lot of coal and gas because we know when it is burned it will reliably produce energy, and cheaply (at least for the cost of the fuel anyway).  Nuclear power can replace coal because it will generate energy reliably, continuously, and cheaply.

Note also the original example quote from the top said “built in year X”.  This means if you had 10,000 MW of power infrastructure, and you built a total of 100 MW more, and it was all wind, you would increase the total capacity by 1%, and even less impressive, the total power by 0.2% (since the wind power only produces 20% of its rated capacity).



Why I’m passionate about nuclear energy

I admit, this is a long read, but there is a lot to be passionate about nuclear energy. 

(and I still couldn’t cover it all)


I would argue that the more time you spend learning about nuclear energy, the more amazing it becomes and the more passion you feel about it.  In short, I see it as the only real solution we have for fighting climate change, but in addition to that, it will also save the human race and bring the world up to a standard of living never seen before – without massive tradeoffs to the environment.  The tradeoffs are not zero, but they are by far the best we have.

Currently, we are working with nuclear reactors that were designed several decades ago.  In spite of that, they are very good, but amazingly inefficient.  However, since nuclear energy is about 1M+ times more dense than chemical energy, it means you can power your house on about 4 pencil eraser sized chunks of ceramic (made from Uranium oxide, enriched).  The chemical way of doing this requires literally TONS of coal. The weight of those 4 uranium oxide chunks?  About an ounce (it is dense stuff).
People love to complain “what about the waste“?  I suggest that even our current trade-offs are pretty reasonable.  “Spent” fuel when it comes out of the reactor is highly radioactive (I’ll tell you why later, it is very interesting).  After about 10 years, most of the radioactivity is gone, but it is still radioactive enough it should be kept out of accidental contact with the environment on a long term basis.  Even so, we are literally talking about ceramic pellets inside metal tubes, it is not like it is some kind of goo you see in bad movies.
The total waste from 50 years of nuclear power supplying 20% of US power, is about 70,000 tons.  That translates to 1 football field stacked 10 ft high.  Not much.  However, about 94% is U238, which could be used as fuel in other reactors, about 1% is remaining U235 and another 1% or so is plutonium (mostly Pu239), both of these which also could be used as fuel in other reactors.
The current “light water” reactors used in the US just don’t bother harvesting this extra energy.  Uranium is so cheap and the energy so dense, that it makes more sense economically to mine more uranium and put the “waste” away.  The funny thing is though, we only use about 1% of the energy from uranium with the current design, but it still kicks butt over chemical burning.
XKCD Log Scale

Thanks to for showing properly how nuclear power compares with burning things.

But that only scratches the surface.  The reactors we use today are solid fueled, and cooled with water.  There are many, many other designs, that are being researched and developed for commercial use.  Solid fueled reactors can’t consume all the energy in the fuel in one step, it requires reprocessing to get at more of the locked up energy.  France and several other countries do this, but either way, you wind up with materials trapped in the uranium and these interfere with operation.

Click to learn more about reprocessing of nuclear fuel

Newer designs propose a liquid fueled medium, you dissolve the uranium (and in some cases, thorium) into a fluoride or other salt, and melt it.  Now that the fuel is liquid, things simply separate by density.  You can skim off the fission products and store them and perhaps even access valuable medical isotopes.  You also can easily add new fuel by dropping in more to melt. Doing this drastically increases your fuel to waste ratio, roughly 99+% of the fuel is consumed since you always can remove reaction products and add more fuel.  These are known as “Molten Salt Reactors”.
Thorium is another amazing thing.  Th232 is the natural isotope, and it can not fission on its own.  It is known as “fertile” not “fissile” fuel.  If it absorbs a neutron (such as in a molten salt reactor above), you can “breed” it to Th233, which then decays to U233, and U233 is fissile.  One more neutron unlocks the energy in U233, which gives out at least 2 more neutrons, and the cycle continues.  Why is this amazing?  Because for one, Th232 is 400x more common than the U235 we consume in reactors today, and requires no enrichment.
Thorium Intro Video

Introductory video about thorium and MSRs

Reactors in the US today require that we take natural uranium (about 0.7% U235) and do isotopic separation (an energy intensive process, but still worth it by far), to bring it up to about 3-5% U235.  You need about 90%+ for a bomb, which is one of many reasons a nuclear reactor can’t be a nuclear bomb.  The result of that enrichment is “waste” (depleted) uranium, and enriched uranium which is (partly) used in the reactor.
Thorium requires no such enrichment – hit it with a neutron, and separate out the U233 chemically to run your reactor.  This molten salt reactor using thorium is called a “LFTR” or “Liquid Fluoride Thorium Reactor” and is one of many designs currently being worked on around the world today, though most are starting with uranium first.
Thorium has another interesting advantage – it rarely makes Plutonium when put in a reactor, and when it does, it makes Pu238 first (not Pu239).  You can separate out Pu238, and it is NOT fissile, so it is not a bomb material.  However, perhaps you have heard of an “RTG”?  An RTG is a radioisotope thermal generator.  We need them to explore space much past mars.  All of our probes that went past mars have one, as does the current mars rover.  It produces electricity purely from the decay heat of Pu238 decaying into other isotopes.  Since the radiation from Pu238 is known (alpha) and easily shielded, space exploration MUST have this substance to any real hope of exploration in the future.  LFTRs would make this material.

Thorium becoming U233 also has value beyond that of power.  U233 decays into very special isotopes that are needed for various industries, and one is being considered for cancer research.  This is no ordinary research.  Picture a radioisotope bonded to an antibody designed to attach to cancer cells.  It is injected, arrives at the cancer site, attaches, and blasts just those few local cells to kill them.  This kind of treatment could work on “impossible” cancers of today like pancreatic and Leukemia.  Idaho national labs (INL) was working on this, though they have been quiet as of late.


Early video on INLs research into Targeted Alpha Therapy

Molten salt reactors run safer too – if there is a leak or other catastrophic event, the fuel simply drains into a tank and solidifies.  The shape of the tank prevents further nuclear activity and it simply cools.  Every accident with a nuclear plant that released material into the environment was a failure of not enough cooling (getting to the reactors in time).  Fukushima could have been prevented by opening up the reactors to the ocean, as it would have cooled them, but they didn’t want to damage the reactors with salt water.
Molten salt and many other designs are also designed to run hotter than current reactors, which means more thermal efficiency.  It also means the “waste” heat (Tcold) can be about 100 deg C, which means you can desalinate seawater from the waste heat.  What would THAT mean to the world?

The higher temperatures would allow us to generate chemical reactions that we now have to burn coal or gas to accomplish.  Many things would be in reach, such as making ammonia from water and nitrogen in the air.  We currently consume over 1% of the country’s energy making ammonia for fertilizer for food and industrial use, that energy is done by fossil.


Watch the entire “Aim High” video, highly recommended. See also other work from Robert Hargraves on this topic in his books.

We use container ships to move things across the ocean, and regulations allow them to burn incredibly dirty “bunker fuel” oil.  This adds the equivalent pollution of millions of cars, all from a few ships.  We could make them nuclear based, eliminating that pollution and probably doubling their speed too.
With reactor fuel now even cheaper than we have now, and the reactors costing less since they can be built smaller, our cost of electric power would drop, far below what we pay now.  What would THAT do to the economy?  What would you spend roughly 5-20% of your extra money on?  Which – many things would be cheaper since…
We could make our own liquid fuels.  You COULD actually burn ammonia for fuel, though it is about 1/3rd the output of gasoline, but we could make plenty of other liquid fuels, removing CO2 from seawater, and the hydrogen from seawater to generate it.  It requires lots of energy, but with nuclear, particularly “Gen IV” (including molten salt reactors) you HAVE lots of power, so we could convert the liquid fuel use of the world to a closed cycle.  Now you get the energy density and portability of liquid fuels (needed for air travel especially) in a closed cycle.  No more CO2 build-up, no need to drill more wells.
When you use thorium this efficiently, the numbers are staggering.  The math works out such that:  If you dug a hole in some average place on earth, and then extracted the thorium to put into a reactor (MSR) and got all the energy out, the energy equivalent would be like filling that hole where you took out the dirt to the brim with OIL… 30x over.   There would be no sense in drilling for oil anymore.
 Thorium Energy Content Merged Final
Every nuclear plant, even with our current technology, saves millions of lives.  By not having to burn coal to compensate for the energy we need, people don’t die from mining that extra coal, processing it, shipping it, and then getting more diseases from the particulate.  Coal plants release far more radiation than nuclear plants).
Nuclear energy has the lowest deaths per kWh than any energy source we currently use, and I’m including wind and solar.  And, I’m including Chernobyl and Fukushima.  Contrary to what people claim (we can discuss that later), the total deaths from Chernobyl were under 100, and Fukushima was 0.  However, the tsunami and suicides from being uprooted killed about 20,000.

People also think we don’t need nuclear sometimes because we have wind and solar.  I did the math, if you replaced just Palo Verde, you’d need about 100 sq miles of solar panels just on a kWh basis.  Worse still, output would be 0 at night, near zero on cloudy days, and 3x too much during the peak.  It is not reliable power, so you have to back it up.  Your options are:  nuclear with no backup needed, coal with no backup needed, “green” with added burning of natural gas as “backup” (most plants rely HEAVILY on natural gas).  As Germany rapidly discovered, as you shut down nukes, you burn more coal.  There is very little you can do about it because nothing else has the power density or stability of these.

These are most of the reasons I’m passionate about nuclear, but there are just so many other possibilities.  How about indoor farms for vegetation?  Cheap electricity means we could grow food in climate controlled, LED lit conditions, with no harmful insects, and thus less chemical use and waste run-off.  It would increase the output of a farm vs its land area many-fold as you could now have what amounts to a skyscraper producing food.  Even a single story would be better though, since fully controlled conditions would more than double yield and cut usage of other chemicals in half.

Going even more sci-fi, since the MSR/LFTR plants are so efficient, and require basically no intervention, why not build them as “robots” (self-running plants).  Use the energy generated to make more of them with energy to spare, and now you have a self-replicating system of power plants.  Your energy cost is now basically 0, since no humans are needed, and all the energy required (which would be your major cost) is made by the plants.

Remember the RTG’s on space probes?  If you really want to explore space, or possibly colonize it, you need nuclear, and a lot more than a few RTGs.  That probably means MSRs, since they are efficient and power dense.

I am convinced that the world does not need to starve itself on a thin gruel of expensive energy, but instead to embrace and develop newer and cheaper nuclear technologies, gaining access to more and more energy.  This energy is what we need to live on and enjoy this planet for all of the billions of people and the billions more that we would be easily able to afford.


Knowing all this, how could you NOT be passionate about nuclear?

What about the waste?

If we are talking about LFTR/MSR power, the waste is minimal and disappears quickly (~100’s not 100,000+ years), but let’s address the waste from standard reactors (typical US light-water).  The graphic shows how fresh fuel becomes “spent” fuel and how it changes while in the reactor.  At the end of the cycle, it is removed and put in a pool of water in the plant, then later transferred to more long-term storage (generally casks).


As you can see from the picture, most of the material left behind is fuel.

Put simply, “spent” fuel isn’t spent.  It is roughly like burning the bark off of wood in a fire then removing the wood.  A hotter fire can burn the wood and not just the bark.

There are newer reactor technologies that could consume currently available “spent” fuel, as well as Canada’s CANDU reactors.

The component that is the long-lived part of the “waste” is plutonium, which comes from U-238 absorbing a neutron (and decaying twice to plutonium).  This plutonium is FUEL.  If it were to be consumed, the long-lived nature of this waste would basically disappear.

There is NO long term waste issue with so-called “spent” fuel.


Our Nuclear Future

What I would like to see for the world’s energy solution.

In response to:

I do NOT like this Energy Gruel rationing idea at all. It flies in the face of anything else I’ve learned about energy.
I agreed with this article up until the very end. We do have good solutions (though not perfect) and we need more energy, not less. Energy directly contributes to quality of life, health and is necessary to the developing world to curb population growth and improve quality of life. If it is not provided somehow, then people will do anything to get it, and that means usually burning dirty sources (biofuel, coal, stolen oil, tar, dung, etc).

We need a source of energy that outputs lots of reliable energy with minimal eco-footprint. I’ve news for you, we already have it and it is nuclear power. While “current/old” nuclear is good, we will be able to do so much better. Exploring first current nuclear, about an ounce of uranium fuel pellets would power the typical US home for a year. By contrast, it takes 4 tons of coal, or about 30 sq meters of solar (in AZ, and you need backup) for the same supply. The same 1 oz of fuel becomes one oz of “waste” which is nothing more than ceramic material housed in metal tubes. The fear surrounding waste and radiation is irrational, but lets just look at some facts – about 70,000 tons of “waste” has been generated from 50 years of US nuclear, supplying ~20% of the country’s demand. It would take up ONE football field, less than 10 ft high.

Now the fun part – that “spent” fuel really has only had a small portion (mostly the enriched U-235) used. With Gen IV designs, we could consume the plutonium that was created, and consume the unused uranium (which is 94% of the remaining “spent” rod). This would roughly multiply the output by ~30-100x and reduce the volume of the waste by as similar amount. Further, the duration of the remaining waste becomes similar to background in about 100-300 years, rather than 100,000+ years.

Not enough? Consume thorium instead – a byproduct from the mining of rare-earths (mentioned in the article), thorium is found everywhere on earth in large amounts. It can be consumed by other Gen IV reactor designs, such as the MSR and LFTR technologies. It too would generate 100-300 year rather than 100,000+ year waste. If we had lots of MSR/LFTR/WAMSR plants, we would have vast amounts of reliable electricity at low cost as well as a number of wonderful “process heat” sources – these can MAKE liquid fuels, which means you can now fuel your planes and cars with sensible, energy dense liquid fuels, rather than throwing away dead batteries.

The future becomes limitless when you focus on this kind of power – space exploration (Pu238), indoor food growth, targeted nuclear cancer therapy (MATT), water desalination, liquid fuel production, medical isotopes, consumption of “spent” fuel, oh… yeah, and electrical power at an actual low cost – making whatever country that implements this an economic powerhouse. Thanks for reading.


Green Tree

Having seen this “tree” around in Facebook memes, I knew it wouldn’t work.  It is about as useless as “solar roads”.
green-treeSo, I did the math (don’t worry, it is pretty painless).

The website itself lists the output of the unit, and for a strong average wind, output is expected at about 3000 kWh per year (they don’t mention year, but the numbers work out).  Since power is worth roughly 15 euro cents per kWh, you multiply and get 450 EUR of output per year.  Divide the price tag by the output, and get:

Wind also has the interesting physical property of the energy content being relative to the CUBE of its speed.  If the average wind speed were cut in half of this example, you can cut your output by 8x, and therefore multiply your time of return by 8, giving you 500 years.

I’m doubting something with that may rotating parts will last much more than 10 or 20, which makes this a net loss in energy, money and sanity.

Does no one check these things before propagating memes, articles, or investing?

Here is the link if you care to do the math yourself: