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Thorium-Fueled Automobile Engine Needs Refueling Once a Century (industrytap.com)
22 points by itomatik 1374 days ago | hide | past | web | 17 comments | favorite

Ridiculous puff piece. The key component for any of this is a working accelerator driven thorium reactor which we don't have. Once we have such a thing, energy ceases to be scarce (at least by current standards). Such reactors are like fusion, except instead of being perpetually 25 years away they seem to be 10-15 years away.


"One benefit of such reactors is the relatively short life of its waste products, which would be in the hundreds of years as opposed to millions of years for existing nuclear reactors."

This line in the wikipedia is outright false. There's no way for a fissioning nucleus to magically know if the neutron that hit it came from an accelerator or another fissioning U atom. Neutron's can't be spray painted green to greenwash / eco brand them to magically make them better than non-greenwashed neutrons.

The rest of the article is more or less true. It misses the two most important uses of accelerator driven reactors. The first is even if you can't generate primary energy and its a net energy sink, you can still transmute elements. So if nasa needs more of specific Pu isotopes for a RTG, you can incredibly slowly create it by burning an enormous quantity of coal without having an actual reactor. Or you could make a plant that overall eats (lots of) electricity and squirts out americium for smoke detectors. The second use is obviously research, you now have a magic machine that eats electricity and while it eats electricity it creates an environment very much like the inside of a real reactor, without the costs and size and weight and security concerns of a normal reactor. Not exactly the same but probably good enough for short term materials science or other fooling around.

Um, I have no idea about how this particular tech works, but neutrons with different momenta can cause dramatically different transitions in the nuclei they strike. No magic required. Is it clear that these neutrons are supposed to have the same momentum as those produced in traditional reactors? That would be surprising.

Yes fasts and thermals generally have varying cross sections. The graph of fission products don't vary much. The "well known" ability to identify which reactor a used rod came from, is because the fission products themselves react to neutron flux, and for materials science reasons no one runs rods to more than a couple percent burnup and long enough to stabilize.

So a rod isn't just 1% used up (a vacuum?) and 99% pure and unused, its first hour of fission at a certain rate resulted in a certain random distribution of nuclei which themselves were irradiated for precisely 2345 hours of full power operation, and then hour two's fission products got irradiated for 2344 hours, repeat. Its a massive summation. What makes it even more complicated is some of the product nuclei are themselves radioactive with a pretty short half life (this is where the ten or so percent of decay heat energy comes from ...) so if you shut it down from hours 1023 to hour 1025 then the end result product will be quite a bit different because you're missing two hours of product isotopes, missing two hours of irradiation for the old isotopes, and the old isotopes decayed naturally for two hours (perhaps into different isotopes, some of which might be radioactive).

If you're really bored, and want to run a big numerical simulation, and have programmatic access to a nuclei table (or just make one up with random data?) you can have all kinds of fun simulating a reactor and summing, decaying, and reacting hundreds to thousands of isotopes under varying conditions and then seeing what you get.

Maybe a TLDR is there are a lot of ways to properly ignite charcoal for a charcoal grill, but the end result cooked steak tastes about the same in the end.

Thunderf00t explains why this is BS: http://www.youtube.com/watch?v=568iDYn8pjc

I will just repeat my comment from an article about the same car two years ago ( https://news.ycombinator.com/item?id=2879219 ):

This is fake or a scam!

There are same interesting quotes in the original article: http://wardsauto.com/ar/thorium_power_car_110811/

First, this is not a nuclear reactor: (at the end of the article)

> This means no nuclear reaction occurs within the thorium. It remains in the same state and is not turned into uranium 233, which happens only if thorium is sufficiently super-heated to generate a fission reaction.

It says that thorium has a lot of energy, not that they can extract it: (in the middle of the article)

> Because thorium is so dense, similar to uranium, it stores considerable potential energy: 1 gm of thorium equals the energy of 7,500 gallons (28,391 L) of gasoline Stevens says.

And the explanation of how it works doesn't make any sense: (at the beginning of the article)

> The key to the system developed by inventor Charles Stevens, CEO and chairman of Connecticut-based Laser Power Systems, is that when silvery metal thorium is heated by an external source, it becomes so dense its molecules give off considerable heat.

The entire story sounds very similar to the presentations of the perpetual moving machines, or the cold fusion: a promise of a lot of cheap energy, but not a working prototype that produce more energy that it consumes.

One look at the website for LPS and you know it's pure BS: http://www.laserpowersystems.com/links/thorium-car/lps-car

What are security implications of Thorium fueled automobiles?

What if someone places an explosive device in it? Or two thorium fueled cars crash? What happens to reactor in these cases?

Is there mini Chernobyl everytime (let's say food/water is poisoned for a month or so) this car collides with something?

I think things like thorium fueled cars would be way more useful for inter solar travels than as cars (Less chances of causing environmental disaster).

I am not a nuclear engineer, so can someone explain the safety risks in the event of a car accident?

google for accelerator driven reactor. They don't work because its too inefficient to run the accelerator, aside from the usual squared/cube issues. I'm sure the first working one will be a fixed station, the next generation will be an ocean going ship, and maybe then a car. Concept cars are a waste of time to consider.

Worst case scenario if you literally ground the car into dust you'd release perhaps ten milligrams of nuclear waste. Why you'd grind an entire car into dust is a mystery. I suppose fed into a compactor and melted and recycled without removing the probably mostly unused and valuable fissionables is possible.

So in an accident would you rather have 10 mg of waste, or 30 gallons of hyperflammable gasoline, or 1000 Kg of lithium batteries, or ...

You're probably better off in an accident with this.

Not to mention that cars already contain many highly toxic materials, like sodium azide to generate gas for the air bags. From Wikipedia: "It may be fatal in contact with skin or if swallowed. Even minute amounts can cause symptoms. The toxicity of this compound is comparable to that of soluble alkali cyanides and the lethal dose for an adult human is about 0.7 grams."

And yet, it's still in pretty much every car. So I think we can probably handle some thorium, too.

10mg of radioactive material can cause a lot more trouble than you think... especially since the hazards are of a less familiar nature than e.g. fire.

But the 10 mg of material are contained inside a ceramic rod in oxide form which won't oxidize because its already oxidized (assuming the designers are smart) and is somewhat refractory in a fire anyway, inside a thick walled steel boiler which is inside some kind of containment thingy and its surrounded by inches (feet?) of metal inside the engine compartment.

On the other hand, 30 gallons of gasoline is in a cheap tank made out of cookie cutter metal so it tears open in a minor crash and there's a puddle of it underneath the seat you're strapped into. And it burns. Really well. So a giant pool of it is currently on fire, underneath your feet. Whoops. Unfortunately this happens fairly often.

The lithium battery is more complicated to model. They burn, really well, but if properly vented they can't explode. So its kind of like driving a truck with 1000 pounds of grilling charcoal in the back... if it ignites, and you just sit there, you'll eventually be grilled like a bratwurst, but its going to take a heck of a long time, so unless you're alone and unconscious in abandoned distant wilderness for 15 minutes you're OK.

Humans are familiar with fire and heat. They are not so familiar with the effects of radioactivity.

The risk is less than you'd think. Things can be contained quite nicely with just some reinforced steel and a bit of water. Accidents should be quite rare too with these self-driving Google cars. Now, I'm not a nuclear engineer, but I did stay at a Holiday Inn Express last night.

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