William tucker has a great article on nuclear energy and why it is superior to fossil fuels and other alternatives. Fossil fuels are concentrated solar energy from fossilized plants and animals that lived long ago. Burning coal is approximately twice as dense in terms of energy compared to burning wood, and oil or natural gas is twice as dense as coal. Wind power, solar and other "renewables" are actually less dense than wood - by a factor of more than 10. Sunlight reaching the ground on a squre yard of the Earth's surface is only enough to power a single 100 watt light bulb, so thousands of acres of land would be required to replace even one conventional power plant. Of course, it isn't sunny all the time either. Wind faces the same issues - the wind isn't always blowing and enormous amounts of land are required to replace a conventional power facility. Biofuels use up around 30% of one of our primary food crops and replace only 3% of our oil needs.
As for nuclear power, read it and weep.
"Remember, when we talked about the energy density of fossil fuels and renewables we talked in factors of 2 thru 50. Do you know what the density factor is for uranium? It’s 2 million. A pound of uranium gives you 2 million times as much energy as a pound of coal. That means you can run a whole city for a week with a lump of uranium you can hold in one hand. In fact a 110-car “unit train” of coal has more energy in the uranium traces in the coal than in the coal itself.
Let’s see what this means in practice. The average 1,000-megawatt coal plant must be fed by a unit train arriving at the plant every day. Such trains now leave Cheyenne, Wyoming every 12 minutes carrying coal from the Powder River Basin to power plants from Nevada to Arkansas. More than half the nation’s rail freight is now coal. In fact, it’s straining the whole infrastructure and we may have to build new rail lines before long.
Now lets’ look at nuclear. A 1000-MW nuclear reactor is refueled by a single tractor-trailer arriving at the plant once every eighteen months. The fuel rods are only mildly radioactive and can be handled with gloves. Over their four-and-a-half-year life cycle those fuel rods will put zero greenhouse gases into the atmosphere. Meanwhile, the coal plant across town will spew 3 million tons of carbon dioxide into the atmosphere. That’s why we have a problem of global warming."
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How in the world is this possible? e=mc , that's how. A very tiny amount of matter can be transformed into a great deal of energy. Chemical reactions, such as burning fossil fuels, occur in the outer electron shell of the atom. Electrons are around 1/1800ths of an atomic mass, the rest lies in the nucleus - thus the amazing amount of energy available in "splitting atoms". The end result is that nuclear is two to twenty times less less impactive to the environment.
What about the dangers, you ask? Well, the uranium used in nuclear reactors is the 235 variety, while the most common occuring naturally is the 238 isotope. Only .7% of natural uranium is -235, so a difficult refining process is necessary in order to obtain the necessary quantities to sustain a nuclear reaction, which is 3% in a conventional reactor. If you want to build a nuclear bomb, the necessary percentage is much, much higher - in excess of 90%. So there is no chance of your local power station going up in a mushroom cloud.
What about nuclear waste, you ask? That term is realistically a misnomer - there is no such thing. Most of the material (95%) that comes out of a nuclear reactor is completely harmless U-235 that occurs naturally and the other 5% was recycled until the Carter Administration decided to outlaw it. Many of the minor actinides (2%) are actually useful in medical applications, but we import all of ours from Canada now because we can't reprocess our own nucelar fuel. The French also make big moeny selling their reprossessed nuclear fuel, exporting it all over Europe and to Japan.
"Almost everything in a spent fuel rod can be recycled. The U-235 can be used again for fuel. So can the plutonium. Among the fission products and minor actinides there are lots of useful isotopes used in medicine and industrial procedures. Forty percent of all medical procedures now involve some radioactive isotope and nuclear medicine is a $250-billion industry."
All of France's nuclear waste from 25 years of producing 75% of its electricity by nculear power is stored in a single room in the basement of The Hague. One reason we got out of the reprossessing field was the fear of nuclear prolifieration, but that is almost impossible - the vast majority of the plutonium that results from commercial reactors can't be weaponized. It takes a special reactor to create the Plutonium-239 that is used to make a nuclear weapon, which is exactly what the Russians were up to a Chernobyl. Nuclear engineers know all this, but the debate has been dominated by the environmental lobby so pervasively that all the facts have been shoved under the rug. It sort of reminds one of the "settled science" of the Climate change myth, doesn't it?
Monday, October 20, 2008
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3 comments:
Excellent, excellent article. Thanks for the valuable information.
I notice a growing tendency to differentiate between two kinds of environmentalists, those who favor nuclear energy and those who don't. In conversations on and off the internet, the first kind are seen as more scientific and the second kind as more political.
Let's hope the scientific viewpoint prevails.
While important, energy density isn't the prevailing factor in deciding which course we should pursue for our long term energy needs.
Of much greater concern is the long term viability of the resource in terms of both energy invested to harvest more energy, and potential environmental degradation.
The Energy Return On Energy Invested (EROEI) for petroleum in the early days was about 1:100. It is now approximately 1:15 and declining, with other fossil fuels following a similar path.
Nuclear energy has variously been estimated at between 1:15 and 1:5. It also is declining as the easy pickings for uranium fuel are depleted.
Breeder technology is even more energy intensive and also contributes substantially to the already high risk nuclear energy poses as a route to nuclear weapons proliferation. To date all countries gaining weapons technology began their quest by building nuclear power plants.
Returning to EROEI, solar is currently providing a return of between 1:20 and 1:40; with wind power between 1:50 and 1:80. The return for both technologies demonstrates a strong upwards curve.
Additionally, technologies for wave, tidal and geothermal energy are quickly moving from the drawing board to the marketplace.
The idea that this clean, safe energy bonanza should be disregarded because it takes a lot of units to produce the required energy is, frankly, rather specious as it ignores the successful mass marketing of other infrastructure (such as roads) and consumer products such as homes, television sets and automobiles. If we were to lump any of those products into their aggregate mass, would you then claim that their deployment and use is impractical?
Philip, thanks for your information. Do you have references for the EROEI numbers? They seem out of line with authoritative calculations that show renewables to be more expensive than nuclear. For example, IEA.
There is a lot of misinformation on nuclear energy floating around, all of it from political groups with their own agendas. What you've said about weapons proliferation is a good example. In fact, the spent fuel from power reactors contains the wrong isotopes for making bombs and they haven't been used in bomb programs. But don't take my word for it. Hans Blix is the former head of the IAEA, the UN agency responsible for preventing proliferation. Here's what he says: [source]
"A phasing out of nuclear power in some or all states would not lead to the scrapping of a single nuclear bomb."
"States can have nuclear weapons without nuclear power though it is not common today. Israel is a case in point. It has no nuclear power but is assessed to have some 200 nuclear warheads. For a long time China had only the weapons. Indeed, most nuclear weapons states, including the US, had weapons before they had power. "
Another example is the remark that high-grade uranium ore is running out. In fact, high-grade ore is being found faster than it's being consumed. Mines around the world have been closing down because of surplus uranium on the market. At present, phosphate miners are discarding uranium because they can't find buyers for it. The surplus of uranium was one of the main arguments against recycling spent fuel, since it would lower demand for new uranium.
I think your last point, arguing that renewables are important to solving the world's energy problems, is exactly right. Very few people argue against it and I'm certainly not one of them. What it will take to blunt climate change is all the renewable energy we can manage, all the nuclear plants we can build, and more conservation than anyone wants.
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