The fundamental problem of pedal-powered generators is that they use human beings as a means to convert chemical energy into mechanical work. Getting away from that, via the coal-fired steam engine, is what allowed us to finally put an end to slavery. Pardon me if I don’t want anything to do with a movement in the other direction.
(That may sound paradoxical coming from me, considering I’ve spent quite some effort working on a suite of human-powered coining equipment, but the rationale behind that is very simple. I should do more muscular work for my health, but I hate exercising. If I could use that muscular effort to produce something tangible, I’d be much more likely to engage in it.)
Many people are surprised to learn that thorium has successfully been used in plain old light-water reactors, such as comprise the preponderance of all power reactors in the world today. The Shippingport PWR was operated as a thorium breeder from 1978 to 1982, with a gain of roughly 1.5% in total 233-U content of the fuel. Simultaneously, the molten-salt concept which many people are intrigued by is applicable to other fuel cycles, & in fact the Gates-funded TerraPower has just announced that it will be working on a chloride-based fast-neutron uranium-plutonium MSR. My own opinion is that there is no one reactor type which has such an overwhelming advantage as to justify using it exclusively ; rather, a wider deployment of atomic power would see quite a mix of reactor types, depending on application & other factors.
I remember you mentioning that point in your atomic energy lecture. I can see your point, but I would point out that as long as we aren’t replacing other power sources with human muscle power, we aren’t really going in the direction toward slavery. Presumably, peddle-power would be a step toward more significant power sources.
Thank you for your insights into nuclear reactor fuel sources. Too often, thorium seems like the best answer, simply because not much is known about it, other than a lot of claims.
Here’s an AEC pamphlet, Thorium the Third Fuel (in PDF). It antedates the Shippingport LWBR experiment, & reflects the information of the time, which assumed somewhat less favourable properties of thorium than later measurements determined. Among present-day reactor types, the Canadian heavy-water reactor (CANDU) is especially suitable for use with thorium, but this development has not been taken up, partly because of the reasonably low cost of its usual natural-uranium fuel, & partly because the politics of “nonproliferation” are opposed to the use of separated or chemically-separable fissile materials, whether that be uranium in thorium or plutonium in uranium, for civilian power-reactor fuels. At one time this was not considered an issue, as witness the use of highly-enriched uranium in the original Shippingport (natural-uranium blanket) & Indian Point (thorium blanket) cores, as a measure to reduce the costs of reprocessing.
The US hasn’t reprocessed any meaningful amount of civilian reactor fuel since the Ford administration, which places a serious obstacle in the way of any breeder-reactor proposal. Molten-salt reactors generally try to get around this by on-site reprocessing, as does the solid-fuel Integral Fast Reactor. It’s interesting to observe that the startup of a reprocessing plant for civilian reactor fuel would immediately allow new nuclear plants to be built in California & other “moratorium” States ; this would be good use for the huge sums of money the Department of Energy has collected for “disposal” of used fuel which continues to sit in pools or casks at the sites even (in some cases) of decommissioned plants. In France they reprocess, re-enrich the uranium, & use the plutonium to make mixed-oxide fuel ; only the fission products then need to be disposed of, although currently re-enrichment is limited by the buildup of uranium-236. Either their originally-planned deployment of “fast” reactors (plutonium-breeders), or the adoption of thorium-based fuel for their current fleet, would provide a way around this limitation.
The great advantage of thorium is twofold. Firstly, it can be used to obtain “breeding” (more 233-U produced than is burned up) with “thermal” (slow) neutrons, & a thermal-neutron reactor is much easier to build than a fast-neutron reactor, so that more than 99% of the world’s atomic power is generated by thermal reactors. Secondly, its use with 233-U produces effectively none of the long-lived transuranic isotopes which result from the use of 238-U in thermal reactors. These isotopes are the main justification for the claims that “nuclear waste is deadly for hundreds of thousands of years” ; while they can be burned up in fast-neutron reactors, see my previous remark. Because of their intense alpha radioactivity, they also make reprocessing much more difficult, at least with present-day methods, because they tend to break down the solvents & other chemicals involved, resulting in “raffinates” & other waste products which are hard to deal with.
Oh, and on the subject of human versus machine power generally :
Incidentally, here’s a great example of what the limitations of light-water reactors using enriched uranium look like. Those very same LWRs, however, as I said before, can use thorium in a closed (breeder) cycle, allowing them to make far more of a contribution to global energy needs.
It would help to get inspired to what we can do in our local community.
How we can help the people here in the Dallas area? We can talk about all kinds of things but someone has to actually do them, so they need to be simple things that work. No need to reinvent something if it already exists.
Let’s find something that we can build together, now. And then we can innovate as we go.
Here is a relevant quote… I think … What do you think?
“We must do away with the absolutely specious notion that everybody has to earn a living. It is a fact today that one in ten thousand of us can make a technological breakthrough capable of supporting all the rest. The youth of today are absolutely right in recognizing this nonsense of earning a living. We keep inventing jobs because of this false idea that everybody has to be employed at some kind of drudgery because, according to Malthusian-Darwinian theory, he must justify his right to exist. So we have inspectors of inspectors and people making instruments for inspectors to inspect inspectors. The true business of people should be to go back to school and think about whatever it was they were thinking about before somebody came along and told them they had to earn a living.” - Richard Buckminster Fuller
