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New research into nuclear's feasibility shows that it simply does not make for a sole fossil fuel replacement.

The death knells of the Earth's dwindling fossil fuel supply have helped to prompt a growing push for alternative fuels.  Whether it be cellulosic ethanol powering the next generation of hybrid vehicles or microbial hydrogen driving advanced fuel cells, America's top technology corporations are making massive investments in alternative energy.  Basically, alternative energy advocates remain split about what is the best solution -- solar power, wind power, biofuels, hydrogen, and nuclear power are seen as the best bets.

Not holding out much hope for an exotic solution, many have turned in the last few years to seriously considering nuclear as a potential replacement to fossil fuel demand.  The result has been resurgence in nuclear efforts.  In the U.S. an application has been filed by NRG Energy for the first new nuclear plant in 30 years.  In Canada, a nuclear research reactor taken temporarily offline was quickly brought online after swift legislative action.

However, despite the growing enthusiasm there has already been one major hiccup.  The record drought that has been plaguing the U.S. Southeast is threatening to cripple the nuclear industry in this region, as many of the plants require large amounts of water.

Now, a new research study, conducted by Physicist Joshua Pearce of Clarion University of Pennsylvania puts another dent in nuclear efforts.  Professor Pearce's research, published in Inderscience's International Journal of Nuclear Governance, Economy and Ecology, indicates that while nuclear research and small-scale growth remain promising, large scale growth remains non-viable.

Professor Pearce is actually an advocate for nuclear power.  He warns that his research should not be misinterpreted.  Professor Pearce suggests that the nuclear power industry focuses its efforts on improving efficiency.  He gives two easy ways to accomplish this.  The first is to utilize only the highest grade ores, saving on refining energy costs.  Secondly, he suggests the industry adopt gas centrifuge technology for ore enrichment, which is considerably more efficient than the currently used gaseous diffusion methods.

Professor Pearce feels that plants must also adopt technology for capturing and distributing their waste heat.  He points out that nuclear plants dump large amounts of heat into their surroundings, a practice which both wastes energy and can cause significant harm to the environment.  Professor Pearce believes that current nuclear weapon stockpiles worldwide should be dismantled and their nuclear fuel "down-blended".  He points out that this could produce a bounty of nuclear fuel.

The not-so-good news which Professor Pearce points out is that nuclear is simply not a viable candidate for large-scale growth.  In order for nuclear power to maintain growing future power demands and the shrinking fossil fuel power supplies, between 2010 and 2050 a growth rate of over 10 percent a year would be necessary according to Professor Pearce.  This, he says, is simply not possible.

Professor Pearce points out that such a growth program would simply cannibalize older plant's power output to provide the power needed to maintain the processes involved with building the new plants and refining ore for them, leaving no power for human needs.  Large-scale growth would require massive power investment in terms of plant construction, plant operation, mining infrastructure expansion, and energy investments to refine ore.  Professor Pearce says the books simply don't balance -- these power needs could not be met by the energy produced from the refined ore.

He points to a significant problem with large scale growth.  Large-scale growth, barring the discovery of new reserves would necessitate the use of lower grade uranium.  This sets an additional limit on growth.  As Professor Pearce points out, "The limit of uranium ore grade to offset greenhouse gas emissions is significantly higher than the purely thermodynamic limit set by the energy payback time."

Professor Pearce also points out to environmentalists and global warming skeptics alike that nuclear power is hardly an "emission-free panacea", as he puts it.  All aspects of plant operation, including plant construction, mining/milling of uranium ores, fuel conversion, enrichment, fabrication, operation, decommissioning, and long-term and short-term waste disposal, require massive amounts of energy provided by fossil fuels.  The burning of these fossil fuels will create large amounts of greenhouse emissions, a criticism oft-leveled against the solar and wind power industries by nuclear advocates.

While emissions are certainly troublesome, the simple energy requirements infeasibility, if accurate, would almost certainly nix the large scale expansion of nuclear power in its current form.  If Professor Pearce's research withstands the test of review then it offers little choice but to pursue his suggested strategies -- develop more advanced nuclear power on a smaller scale and pursue other alternative energy solutions as a major source of capacity.

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By BlackIceHorizon on 3/6/2008 5:52:06 PM , Rating: 2
The factor that I suspect Professor Pearce's analysis really fails to consider is that we (still) have the ability to utilize virtually all natural uranium, not just the less than 1% (U235) we use now. All nuclear reactors convert a portion of the U238 (the "other" Uranium that doesn’t support chain reactions, still composing 97% of fuel after U235 enrichment) in their fuel into Plutonium 239. This isotope is fissile like U235, that is, it can support a nuclear chain reaction. It can then go on to fuel the reactor in the same manner as Uranium. In traditional reactors the ratio of this fuel "breeding" is fairly low, say around 0.3. Thus, the fuel eventually becomes less effective and must be disposed of as high level radioactive waste. It still consists of over 95% unreacted Uranium! It is possible, however - and with present technology - to produce reactors with breeding ratios greater than 1.0. That is, they produce as much or more fuel than they consume. These could use depleted Uranium (DU) as fuel. By using less than 1% of the Uranium we mine, we in fact could deplete present reserves somewhere after mid century ( Breeding fuel from U238 would multiply our reserves by 2 orders of magnitude, allowing for the scaling of nuclear power to become the major energy source for at least the next century.

How abundant is depleted Uranium? It's so cheap that we currently form it into solid projectiles (bullets) and shoot it at enemy tanks for its armor piercing abilities. Even with this and other uses we're constantly accumulating more as a byproduct of enrichment. The U.S. government currently stores 470,000 metric tons of the stuff ( They can't get rid of it. This is hardly surprising considering that it composes over 99% of the Uranium we mine. If we devoted a small portion of the energy budget (just taking away half of the fossil fuel industry's current $10billion in annual subsidies would do it - it’s currently less than a 10th of that) to supplementing research on 4th generation nuclear reactors of the breeder type, any fuel supply issues would be definitively solved. Our nuclear waste production would also be reduced by over an order of magnitude. That's right, even if we switched all electricity production in the United States to advanced nuclear, a 5X increase over present levels, we would produce less nuclear waste than we do now. And remember, when I say advanced I don't mean pie-in-the sky down the road nuclear (I’m all in favor of long term research, but come on Mr. Pearce, do you honestly think Fusion can be assured to produce commercially and economically viable power on global scales in the next 30 years?), I mean now. Full scale (1200MW), functional advanced breeders have already been built, and they worked . If we started now we could introduce this technology in the U.S. on a commercial scale within a decade (

Professor Pearce is absolutely right that we should switch from diffusion based enrichment to centrifuge based enrichment. He’s also right that we should reprocess old weapons stockpiles into fuel. These will only increase the efficiency of nuclear power further. The second can’t be done until the U.S. reworks its defunct cold war era policies and starts a serious reprocessing RD&D program. This, coincidentally, is integral to the viability of the extremely promising breeder reactor technology.

The reasons breeders haven’t been used significantly to date have been twofold:

1) Fears of nuclear proliferation.

2) In the past it has cost more than just using enriched Uranium.

We have solutions to both of these problems. First, breeder reactors can be designed to make them useless for producing weapons grade materials ( - see “Possible technology risks” section). Second, as Uranium supply becomes tight and prices increase while improvements in breeder technology decrease breeding costs, it will make economic sense to switch to breeder reactors, which use their fuel over 100X more efficiently and can transform our already massive stockpiles of DU from a liability into a resource.

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