It seems like they have many advantages over conventional water-based reactors and are much, much safer to boot. Also the waste products decay quickly so storing the waste for long periods of time is less of an issue. But I guess anything nuclear is pretty much out of fashion today.
I guess you could theoretically pull salt out of the water, but there is no telling what impurities may be left. Reverse-osmotic water filtering makes water so pure that it supposedly extracts minerals back out of your bones and teeth, so impurities are no concern when it used as an exchange fluid.
The "die hard" MSR guy in the US is Kirk Sorensen of Flibe (Flih bee) energy: flibe-energy.com He's easy to find from a Google search, and is incredibly dedicated to MSR. He's the evangelist, for sure.
Bram Cohen of BitTorrent fame is on Flibe's advisory board.
I suppose Ford realized that having fissile material in every garage can prove to be a bit of a hazard.
And as far as cars go, I'd rather have a self-driving car than a nuclear car.
Just one small change like this, nuclear instead of gasoline in the cars could make a tremendous impact on our lives.
I think adding a new variable to the existing capitalist system along with existing one and only, profit, something that takes into account health or the ecosystem could change our lives dramatically.
Entrepeuners competing not only on cost and profit but also on health and ecosystem impact could make a big difference to us and our planet.
It will be great that we finally realize how important stuff like this is and focus more on research instead of using 100 year old polluting technologies because there is no obvious pressure to move forward.
Second, the new variable you're thinking of is called "externalities" and isn't all that new. A common way to offset it is http://en.wikipedia.org/wiki/Pigovian_tax - a such is leveraged on gasoline in most countries, including the US, although to a much steeper degree in Europe. Expensive gas is a major driver towards more fuel efficient cars, hybrids and electric cars. All brought to you (mostly) by a profit driven capitalist system.
The reason gasoline hasn't disappeared in favour of more environmentally friendly alternatives is that it's an insanely effective way of storing and transporting vast quantities of energy. Even with the steep taxes in Europe, no-one has been able to come up with a better alternative -- yet. I am certain this will change soon.
I hardly think that this would qualify as a small change.
A regular car motor produces up to 90kW.
10000 miles at 40 mph average is 250 hours, or 2,500 hours over the 10 year. It's low speed, so let's assume the engine runs at half the rated output on average, 45kW, for a total of 112 GWh or 12.8 kg uranium.
The classroom stuff is $90/kg, or $1,152 total fuel costs for ten years.
Edit: more importantly, though: nuclear reactors are very poor at variable power output, so they are a bad fit for cars. Perhaps long haul trucks.
Here's real numbers from the industry . You use $90/kg. They say on the the order of $3,000 per kg of reactor-grade UO2, which is $60,000-$90,000 per kg of the U-235 isotope.
On the flip side, you're greatly overestimating fuel usage (your assumptions are equivalent to about 6 mpg mileage), and you have a unit error where you accidentally multiplied by one thousand (45 kW * 2,500 hours = 112 MWh, not GWh!). So the figure is about 1/3,000x yours: about 5 grams U-235, or 100 grams reactor-grade fuel, or 1 kg of natural uranium. Costing on the order of $300.
This doesn't apply to (imaginary) nuclear cars. With reactor-grade fuel, you need hundreds of tons of uranium, and hundreds of tons of moderator, to get a critical reaction. This won't fit into a car. The only way to approach a reactor this small is to use highly enriched fuel -- "weapons-grade", which is not sold at petrol stations. This is how they miniaturize reactors to fit in submarines and space satellites (like , not an RTG).
If you did try to build a car like this, it be pathologically wasteful. The amount of HEU would need to be several kg or more, to have a critical reaction at all. But because a car uses so little power, you would burn less than 1% of it (several grams) over hundreds of thousands of miles. Extrapolating (using ) enrichment costs ($150/SWU from ), the fuel cost would be on the order of $300,000. And almost entirely wasted.
An engineering buddy and I tried doing the math for getting cars up on the same configuration, but quickly realized that albeit each vehicle would contain miniscule amounts of uranium, someone could buy up a bunch of them and aggregate a large amount of uranium (bad).
For trains or large hauling vehicles it would be perfect, but most of the new trains/rail receive their electricity via some track delivery mechanism anyways.
Interesting fact: For engineering reasons, the engines in the trains do not directly connect to the wheels. Instead, they operate generators that power electric motors attached to the wheels. Installing a nuclear power plant would be as simple as adding another car to the train and changing around some wires.
always wondered about its feasibility; interesting to see it was based on a real-world concept (though a very unrealistic one at that).
though i wonder how life would be different if nuclear really had gained traction and supplanted fossil-fuels as our primary energy source.. today a concept like this seems laughable (to me anyway), but i'm thinking given the atmosphere back then and considering all the promise nuclear held, it wouldn't have been that ridiculous to imagine a time when mini-reactors could be powering passenger vehicles. i know the science behind it is far more complex, but just like computing devices have evolved and gotten increasingly smaller/safer/more-reliable over time, so too could nuclear reactors i imagine..
The design was finally abandoned not because it was impossible to do - quite the contrary. Both US and Russia had working nuclear-powered engines. But it was deemed too dangerous to actually use. In case of a crash a large area would be contaminated.
So the only possible application for a nuclear engine is on a intercontinental missile carrying nukes, because you don't care about the fallout and it would have unlimited range.
Post something mildly interesting or controversial from wikipedia. Mind you does not have to be new or newsworthy.
People click on it and fall into the wikipedia loop, reading about related topics clicking around wikipedia semi-aimlessly.
Wastes a ton of time and kills a man-month or so of productivity (or more at HN scale). No good comes of it except people feel entertained.