posted November 22, 2005 14:31                      

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...in general it's probably a reasonable way of tackling fossil fuel over-usage.

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posted November 23, 2005 17:36                      

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Originally posted by nerdwithnofriends:
pure hydrogen has turned out to be a pretty poor fuel when used as a combustant.

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No kidding! All the cool fuels combust with visible flames, ideally shooting out of the exhaust of a top-fuel dragster in an environmentalist's bad dream. However, you can see the shock diamonds forming in the blast coming out of the SSMEs, so hydrogen does have some redeeming qualities.

posted November 24, 2005 00:14                      

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Instead of the typical rod-shaped fuel, the fuel is formed into "pebbles" about the size of a pool ball. Each pebble is made of grains of uranium sheathed in heat-resistant graphite and silicon carbide. The 100 million-watt reactor is supposed to use 310,000 fuel pebbles.

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posted November 29, 2005 02:04                      

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Originally posted by AntonTakk:
I'm not to sure on the feasability, (economic or otherwise) but someone once proposed the idea of launching nuclear waste in to the sun. Or if that can cause problems for the sun that I don't have the education to realise, space is rather vast, and we'd only need one black hole.

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posted November 29, 2005 02:23                      

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Originally posted by AntonTakk:
I'm not to sure on the feasability, (economic or otherwise) but someone once proposed the idea of launching nuclear waste in to the sun. Or if that can cause problems for the sun that I don't have the education to realise, space is rather vast, and we'd only need one black hole.

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posted June 21, 2007 21:49                         

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Originally posted by nerdwithnofriends:
I'm actually very much pro-nuclear power. The thing is, 97% of nuclear waste can be recycled and made into re-fissionable fuel. There are experiments going on right now to build reactors out of graphite, and somehow that prevents melt down when something goes wrong.

Also, a US company has been experimenting with building fission processes that release a large amount of hydrogen as a byproduct, thus providing hydrogen to fuel engines. Don't delude yourselves about this one, though, as pure hydrogen has turned out to be a pretty poor fuel when used as a combustant.

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I'd like to point out a few errors in your para, if I may. Firstly, regd the 97% stat that you've given, I'm not sure about how accurate that is, but from what I remember in high school, (warning: readers with better things to do, lecture coming up, feel free to click the 'Back' button on your browser) nuclear fuel consists of small quantities of fissionable U-235, and the rest is U-238. After usage, the 'waste' consists of plutonium-238, U-238, and the real waste, which depending upon the type of fission conducted, could be molybdenum, lanthanum, and similar medium-mass toxic elements. What the process of recycling basically does is it separates the U238 and plutonium and since its fissionable, uses it to develop weapons or further power generation. ONCE! Whats left is small quantities of toxic waste, still almost equally potent as before the recycling, but smaller in volume. After treatment, its Yucca'd. Personally, I'm against dumping, as that brings up a whole lotta issues in the future. I'd like to see it all shot towards the Sun, but right now, thats economically unfeasable.

Regarding the Hydrogen products you're talking about, I haven't heard of this one, but I'm guessing it'll be the same old catalytic cracking they use, probably taking advantage of the readily available boron in nuclear plants, and the elevated temperatures. I'm totally pro a hydrogen economy, but have you guys read Popular Mechanic's November '06 issue? The problems related to hydrogen production, transportation, storage, and use are IMMENSE!!! Except for use in automobiles, hydrogen is unviable to run a country on. Its been explained really well in the magazine, and should be available on the website. If anyone likes, I can put up a few points here, but it should be easy to get anywhere on the net. It really brought me crashing down when I read it. Seems like we're back to the wind/solar/water trinity again. Just hope those high efficiency photovoltaic cells are coming along quick, last I read the average efficiency of industrially used solar cells was pretty low, 8-18% I think. Bad, what?


Oh, and the US policy of not recycling nuclear waste should be changed. That policy was drafted 30 odd years ago to prevent arms proliferation. I'm not saying the risk is gone, but the benefits are far greater. And hey, why would anyone go to all the effort of stealing and smuggling all those hazardous materials all the way out of the US, across an ocean or two, and then the odd continent, when North Korea's offering it without any hassles?

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The Force. It surrounds us. It enfolds us. It gets us dates on Saturday Nights.

posted June 21, 2007 21:58                         

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Originally posted by supaboy:
Breeder reactors are simple in theory but none have been able to work well in reality.

Plus, when you mention using plutonium for fuel, laypeople tend to get even NIMBY-er than normal about nuclear power. And there are a lot more of them than there are of you!

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posted June 24, 2007 12:27                         

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In 1998, the U.S. Department of Energy set a goal to double the use of cogeneration by 2010, which could potentially add 46 gigawatts of capacity - about the equivalent of 92 500-MW power plants. Analysis by the American Council for an Energy Efficient Economy (ACEEE) found that the DOE goal is not only achievable, but could be readily surpassed.

Industrial CHP

Combined heat and power (CHP), also referred to as cogeneration, is the onsite generation of electricity and heating or cooling from a single fuel source.

To understand the advantages, it is helpful to first think about grid power. Electricity sent along the utility grid is about 27 percent efficient; as much as 73 percent of the input fuel is lost by the time power reaches end-users at the socket. About 65 percent of this fuel is lost as waste heat, a byproduct of generation. Another 8 percent or so is lost along transmission lines.

CHP limits these losses by recapturing waste heat and reusing it as a source of heating or cooling. Not only does this save energy otherwise lost up the smoke stack, it also reduces onsite energy demand.

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posted June 24, 2007 14:41                      

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Originally posted by ASM65816:
My vote is for Combined Heat and Power (CHP) systems...

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