Randall Munroe, who is usually fairly knowledgeable about these things, says the water in spent-fuel pools is usually at 25 to 35 degrees Celsius. Not really boiling off, then, and probably doesn’t need a lot of external cooling after all, either.
You could go for a swim in a spent-fuel pool (divers do it routinely for maintenance) and it would be unlikely to be harmful unless you dove all the way down to the bottom and bodily touched the fuel rods. See https://what-if.xkcd.com/29/ .
So Wendover got that wrong…they could easily have said the water evaporates away or cited a temperature, as Munroe does. They were pretty strong on the pool needing power though, citing Fukushima as an example of a near disaster.
I see one of the reason why nuclear power has failed to catch on, right here: the citation of different but equally true facts — depending on constraints and context that are never explained — makes it hard to make decisions.
It depends a lot on how “fresh” the fuel rods are, and the size of the pool is also a factor. When the fuel rods are newly out of the reactor core, they’re pretty hot (in terms of temperature if not radiation), and the water from the pool usually needs to be passed through a heat exchanger to make sure the temperature of the pool stays below 50°C, so some energy is needed to drive a pump. After a couple of years in the pool the rods cool down. The problem with Fukushima 4 was that the fuel rods there were basically straight out of the reactor, so when the water pumps failed a lot of the water in the spent-fuel pool did eventually boil off (which is not a Good Thing).
If the spent-fuel pool is working correctly there is basically nothing to worry about because the water shields the radiation from the fuel rods very efficiently. Munroe argues that if you tread water in a spent-fuel pool you are actually getting less radiation than if you are simply walking around outside, because the water on top of you shields you from the ambient natural background radiation, and the fuel rods at the bottom of the pool are of no consequence because they’re also shielded very well by the water above them.
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I don’t know that anyone has done it recently, but the last couple of times it was done the numbers were continuing to get better as biodigester technology has continued to develop. Unfortunately a lot of the recent work in this area is patented, but basically several companies have demonstrated ability to derive fuels from crops that require little in the way of tilling or soil amendation.
The carbon in agriculturally derived fuels is extracted directly from the atmosphere (it is not taken from a geological sequester deep underground and then released into the air) so burning them does not contribute to air pollution or the greenhouse effect; the same amount of carbon (or more) would be released by the natural decomposition or consumption of the plants. Thus, agriculturally produced methane is carbon neutral and is currently the highest efficiency method of mass-converting sunlight to long-term storable power.
It is not necessary to use fossil fuels to produce crops for methane production. The corn and oil industries have been spreading this lie in order to maintain their market dominance.
Personally, I use literally no fossil fuels to run my 1973 tractor or to fertilize my food garden.
Naw, try flying over the US from coast to coast and you can see for yourself that this is more industry disinformation, not a reality. Sustainable, carbon-neutral fuels don’t need carbon sinks anyway.
I think nuclear technology could theoretically be made safe (I have written software for nuclear power plant control (Infotrol programmers, represent!) and I have worked with nuclear power satellite and nuclear weapon delivery systems, so this isn’t entirely outside my field of experience) but nonetheless I think you are right, history clearly shows we haven’t done so, and are unlikely to do so under current political and economic models.
Not when you take land use changes into account. See for example:
http://science.sciencemag.org/content/319/5867/1238
If you assume corn ethanol, and don’t use any technology less than 150 years old, and ignore sustainable farming practices and new biodigester technologies, then you are correct.
But again, these problems are all solved at this point. Dr. Diesel solved the tractor fuel problem in 1900.
Perhaps you should read the paper I linked, rather than guessing about its assumptions.
Are you going to pay for my access to a paper published in 2008?
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