Monday, October 25, 2010

New Nukes

From Whole Earth Discipline: Why Dense Cities, Nuclear Power, Transgenic Crops, Restored Wildlands, and Geoengineering Are Necessary by Stewart Brand, pp. 81-82:

As to footprint, Gwymeth Cravens points out that “A nuclear plant producing 1,000 megawatts takes up a third of a square mile. A wind farm would have to cover over 200 square miles to obtain the same result, and a solar array over 50 square miles.” That’s just the landscape footprint. [....]

More interesting to me is the hazard comparison between coal waste and nuclear waste. Nuclear waste is miniscule in size—one Coke can’s worth per person-lifetime of electricity if it was all nuclear, Rip Anderson likes to point out. Coal waste is massive—68 tons of solid stuff and 77 tons of carbon dioxide per person-lifetime of strictly coal electricity. The nuclear waste goes into dry cask storage, where it is kept in a small area, locally controlled and monitored. You always know exactly what it’s doing. A 1-gigawatt nuclear plant converts 20 tons of fuel a year into 20 tons of waste, which is so dense it fills just two dry-storage casks, each one a cylinder 18 feet high, 10 feet in diameter.

By contrast, a 1-gigawatt coal plant burns 3 million tons of fuel a year and produces 7 million tons of CO2, all of which immediately goes into everyone’s atmosphere, where no one can control it, and no one knows what it’s really up to. That’s not counting the fly ash and flue gases from coal—the world’s largest source of released radioactivity, full of heavy metals, including lead, arsenic, and most of the neurotoxic mercury that so suffused the food chain that pregnant women are advised not to eat wild fish and shellfish. The air pollution from coal burning is estimated to cause 30,000 deaths a year from lung disease in the United States, and 350,000 a year in China.

As for comparing full-life-cycle, everything-counted greenhouse gas emissions, a study published in 2000 by the International Atomic Energy Agency shows total lifetime emissions per kilowatt-hour from nuclear about even with those of wind and hydro, about half of solar, a sixth of “clean” coal (if it ever comes), a tenth of natural gas, and one twenty-seventh of coal as it is burned today.

And what can we do with the nuclear waste? Lawrence Livermore National Laboratory has an interesting idea: the Laser Inertial Fusion Engine (LIFE), a combined fusion/fission reactor in which the high-energy neutrons produced by fusion “burn” fissile material, like “depleted uranium; un-reprocessed spent nuclear fuel (SNF); natural uranium or natural thorium; or [...] plutonium-239, the minor actinides such as neptunium and americium, and the fission products separated from reprocessed SNF.” The result? “The LIFE engine extracts more than 99 percent of the energy content of its fuel, compared to less than 1 percent of the energy in the ore required to make fuel for a typical LWR [Light Water Reactor]. Higher fuel utilization means that far less fuel is required to generate the same amount of energy. A 1,500-megawatt LIFE power plant could operate for 50 years on only a small roomful of fuel.” The “remaining waste has such a low actinide content that it falls into DOE’s lowest attractiveness category for nuclear proliferation.” Securing the waste apparently won’t be much of a problem, because “the waste is self-protecting for decades: its radiation flux is so great that any attempt at stealing it would be suicidal.” OK, that gives me pause for thought, but, then, that’s part of why nobody in their right mind would try to steal it. And for those not in their right minds, there’s the actual suicidally lethal radiation that sounds like it would kill them before they could steal the material. Fortunately, the volume of waste produced is relatively low: “[...] approximately 5 percent of that required for disposal of LWR SNF.”

Intriguing. All things being equal, I prefer pure fusion, but putting our nuclear waste to good use makes a lot of sense, since we have to do something with it one way or another, and extracting vast amounts of energy from it, while reducing its volume, seems like a good start. And dealing with that waste looks like a much smaller and more tractable problem than dealing with the wastes we’ve been spreading over the planet by burning coal.

The possibilities of fusion and/or LIFE reactors aside, I think Stewart Brand makes points concerning the desirability of current, and near-term, methods of fission power production that deserve careful consideration from everyone, especially my fellow environmentalists.


  1. Alison in Indiana8:39 AM CDT

    "A wind farm would have to cover over 200 square miles to obtain the same result,"
    The wind mills are spread over that area, but the land around them can still be used for farming, ranching, etc. So the foot print is not a great as this writer is claiming.

  2. How much room does 5 billion cans of coke take up? Or 10 billion? How much does it cost to safely contain it for all eternity?

  3. jdb,

    Don't forget to ask the same question about coal, or any energy production scheme that generates a waste product when the hardware is built, operated, or decommissioned. Since coal burning is, has been, and (regrettably) will be for some time yet, our primary source of power, lets concentrate on that. So, what does it take (in terms of space, facilities, etc.) to capture and store all of the greenhouse gasses, neurotoxic heavy metals, radiation and all the other undesirable substances produced by burning coal? Don't forget to go back to the very beginning of coal-fired power production, since we've been externalizing almost all of those problems for a very long time now. (And how does one arrive at a cost for removing all of the heavy metals, for instance, that coal-burning has already blanketed the world with? Beats me. I think the best we can do there is hope that over time they become locked-up in soil strata, ocean sediments, etc. and that nothing ever stirs-up a significant amount of them.) In contrast, the nuclear waste from all of our nuclear power plants is currently, and to my knowledge, always has been, safely stored.

    What does it cost to store coal or nuclear waste products for all time? An infinite amount of money, obviously, which makes that question meaningless. A question to which there should be an actual, computable answer is: what does it cost each year to store the waste produced by our nuclear power plants? Multiply that by the number of years that you expect technological civilization to continue, divide it by waste reduction technologies like the proposed LIFE reactors that will come along in that time, factor in nuclear decay, and bear in mind that whatever sum you arrive at is paid-off in convenient yearly installments.

    Do the same calculations, if anyone can, for the waste products of our history (and, at this point, foreseeable future) of coal burning. And bear in mind that almost none of those waste products have ever been captured, let alone safely stored; you'll need to factor in the costs associated with those externalizations, which I think we can safely say are staggering, even before the costs of global climate change are added in.

    By comparison the nuclear waste problem, in terms of size, cost, etc. is trivial.

    Having said that, I like the idea of a "permanent" means of disposing of hazardous wastes at least as much as the next guy. So it's not my intention to blow-off your question, just to add some of what I believe is badly needed context and qualifiers.

    Personally, I've always wondered about—and I don't know what the professionals have made of this notion (it can't have escaped examination)—is placing the hazardous waste that we can foresee no use for, and feel we absolutely have to get rid of right now (and opinions will vary about what waste falls into that category), into the most active subduction zones in the deepest areas of the world's oceans. Provided they can be kept in place until they've been subducted, they'll essentially return to where they came from in the first place.

    (Remember that the nice, hot core of planet Earth is believed to acquire 80% of its temperature from radioactive decay, continuously adding, according that article, an average of 1/10th of a Watt of heat to each square meter of the Earth's surface. Admittedly, getting the waste material into the upper mantle isn't the same as placing it in the inner or outer core, but, presumably, the mantle is no stranger to radioactive materials – the crust we all occupy had to get them from somewhere, after all.)