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Uranium is as common a tin and 40 times more common than silver. Coal contains more energy due to uranium impurities than it does due to the chemical energy contained in coal.

http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html

<sarc>Shit, if uranium is only as common as tin and produces 10 million times the energy on a mass per mass basis as coal, how will we ever be able to solve our energy crisis?</sarc>

Also noteworthy: We have the worlds largest reserves of Uranium and we know how much the superpowers love that shit...

You have a couple of misunderstandings going here.

The first is that uranium ore isn't harmless while still in the ground. If you live somewhere rich in uranium, even though it's all mixed up in the soil, you have to deal with radon gas in cellars and basements.

Second, they aren't so much "concentrating" it as enriching it.

Uranium Fuel Production

It's a matter of sorting the less stable atoms out from among the more stable ones. Once you have the unstable ones all mixed up together, it's a nasty and dangerous business to try to mix in stable ones again and make it safer. If you mix in the wrong things, you end up slowing the reaction in just the way that will make the material worse... or even explosive.

The end products of nuclear power aren't uranium at all, they're much more unpleasant. Many of them don't occur naturally.

The main point is, you can't use your chemical intuition to estimate how nuclear products work.

Widely unnoticed by the general public, which is all caught up in Peak Oil yes-or-no discussions, Uranium faces the very same problems as fossil fuels, but they seem to be worse.

From this article: In 2001 the European Commission said that at the current level of uranium consumption, known uranium resources would last 42 years. With military and secondary sources, this life span could be stretched to 72 years. Yet this rate of usage assumes that nuclear power continues to provide only a fraction of the worlds energy supply.

And here is the actual development of Uranium price over the last century:
http://www.uranium.info/prices/monthly.html (note that the peak around '78 about coincides with the peak of the US and Soviet nuclear arsenal during the Cold War)

And here you have, again, the development of Uranium prices over the past 4 years:http://www.cameco.com/investor_relations/ux_ history/historical_ux.php(flash required for the small graphic, but the numbers are there in plain text)

Now if not only China builds dozens of reactors, but the western industrialized world as well, nuclear (i.e. fission) energy stops looking to be very attractive in the long run. Give us fusion (hot or cold), or give us renewable energy as our main source, but don't try to balance two resources which are ultimately limited and might well be seeing their practical end within our century. Don't floor the gas pedal if you know you will have to stop eventually, either by slowing down yourself or by being slowed down by a concrete wall.

- Nuclear doesn't do anything for our vehicles, which are 50% of the emissions problem

Perhaps it doesn't, but if we get rid of ~half of the problem, then haven't we made big strides?

- I really wish we knew how much Uranium we have

As to the amount of known uranium, here's a couple links: cameco.com's Alberta data & the wikipedia uranium article.

I hate to break it to ya, but at least one of the byproducts of nuclear power (Plutonium) isn't around in your backyard

No, but there's plenty of Uranium. Plutonium should be burned up rather than stored as waste.

It also happens to be one of the most toxic substances we know of

Bullshit. It doesn't rate even close. Let me ask you, which would you rather ingest: 20 grams of caffine or 20 grams of plutonium?

If you value your life, you'll go for the plutonium.

What happens if the US descends into anarchy as a result of a stock market crash 100 years from now? Still safe? We've still got to deal with the stuff. And keep guards on the storage sites.

Safe from what? Your overactive imagination about glowing mutant babies? Most of the stuff they (will) stick in Yucca Mountain isn't even dangerous enough to shield against. Most of the stuff is only dangerous for the first month or so. (Which will stay in cooling pools until it cools off anyway.) The only real danger posed by the spent fuel is if it makes its way into the water table. That could cause an increase (not an epidemic, mind you, an increase) in the cancer rates.

If you have a SPECIFIC concern, please share it with us and I'll be happy to refute it. Otherwise stop watching so many bad movies.

Actually, this thing here heats up the river a little bit!

Natural Gas plants are currently significantly cheaper per megawatt than nuclear.

A nuclear plant's construction costs are substantial relative to other types of power plants. However, once a reactor is built, it is cost-effective to keep it running at high capacity. As a result, utilities operate nuclear reactors as base load power. In contrast, it is normally prudent for utilities to respond to short-term changes in the demand for power by increasing or cutting back generation at their fossil fuel power plants.

Nuclear electricity production costs were cheaper than coal, oil and natural gas in 2002.

According to Resource Data International (RDI), nuclear generation costs in 2002 averaged 1.71 cents (US) per kilowatt-hour, lower than coal at 1.85 cents (US), natural gas at 4.06 cents (US), and oil at 4.41 cents (US).

A more comprehensive cost analysis conducted by the European Commission (EC) in 2000 took into account both internal and external costs. Internal costs include operating costs such as labour, fuel and supplies, plus capital expenditures, for all elements of the nuclear cycle, from exploration to decommissioning and waste disposal. External costs are the costs reflecting damage to the environment and the negative impact on communities: how much the activity contributes to global warming through greenhouse gases, and how large a "footprint" it leaves on human health.

The EC study concluded that the cost of electricity generation plus environmental factors for nuclear is substantially below that of fossil fuels, and it does not produce any greenhouse gas emissions.

Ha, while that is true for the Earth as a whole, it might add politically significant amount of uranium isotopes to some dude's backyard in Florida and that counts 100x more than all the output of coal plants combined globally.

Did you know that uranium is one of the most common substances on Earth? You probably already have some in your backyard. Raining some from an engine would NOT increase it by that much. It certainly wouldn't kill you in the time it takes for the nuclear energy commission to clean up your neighborhood.

Did you know that old style X-Ray machines would give you up to 10 REMs of X-Ray radiaition per X-Ray? Modern digital machines give off only about 10-100 millrems, but if you are older than 15 you may have had an X-Ray from an older machine.

You'll note BTW, that it did not instantly kill you or cause your skin to melt. In fact, doctors considered it quite safe as long as they made sure not to give you too many X-Rays.

When it comes to nuclear power, the real dangerous stuff is the heart of a very large reactor. Older reactor designs would keep hundreds of pounds of material under pressure so that they could produce large amounts of power. In the case of a melt-down and boiler explosion, a lot of hard radiation would be exposed to people near by. (And I mean people within about half a mile. Radiation falls off at the same rate as light, so give it just a little distance you won't get any more than you would from your CRT.)

Here's the upside about the "hard stuff". It doesn't last. In order to be energetic enough to kill someone, it has to have a very short half-life. Within an hour, a reactor's core has already lost much of its most potent stuff. Within a few days it may even be safe enough to approach. Within a month they could cement over it and forget it existed.

I should probably mention that modern reactors can't have a boiler explosion like Chernobyl. Those designs were deemed unsafe long before the incident, and were decommisioned here in the US. Chernobyl OTOH, was built with *decreased* safety precautions because the Russians thought they were unnecessary. Contrast that to Three Mile Island which shut down exactly as it was supposed to.

Some interesting statistics for you. Currently, there are ~500 nuclear reactors in the world, plus the 50+ used by US Navy Vessels (8 on the Enterprise alone, 2 on a standard Nimitz carrier, and 1-2 on each nuclear sub), plus about 550 research reactors operating worldwide. Nuclear reactors are well understood things at this point.

I must admit that from what you are describing the engine would look completely different from what I have seen in some old magazines, it must be some completely new concept, if you have some links to sites (with pretty diagrams for ignoramuses) I would appreciate.

Wikipedia explanation of various proulsion methods

NERVA and GCNR engine descriptions

You're probably thinking of NERVA engines. NERVA engines would melt off the back of a rocket and drop from the sky like a rock (a very heavy rock) if they were to melt-down (although they run pretty close to melt-down normally). Gas Core Nuclear Rockets (GCNR) use a uranium plasma vapour for heating the propellant. This is in many ways easier to contain in an emergency than a tradiational nuclear pile.

BTW, I should probably point out some of the safety features of nuclear rockets. For one, they have more power, so they can be built of more traditional and well understood materials. Many chemical rockets go for exotic composites to keep weight down. The other advantage is that the fuel is what cools the engine. In the case of a runaway nuclear reaction, the turbopumps can deliver more fuel to cool the reactor

Well, I have to take your word for it, but cannot believe it, since Uranium has a greater atomic mass than Gold, which would make it less common fission product than Gold and is more unstable than Gold, which makes the product even rarer.

Actually, Uranium is about 500 times more common than gold. It's a *very* common substance. IIRC, most of it gets deposited on earth from meteroites (including the ones that burn up). You'll be pleased to know (sarcasm) that coal generally contains high levels of Uranium and that coal burning disperses large quantities of Uranium in populated areas.

Which requires next to no technical expertise and doesn't enables one to build atomic bombs (Hint: Sarcasm)

I didn't say that it doesn't require expertise. I said that anyone with the proper resources (ususually enough money to train or hire scientists and buy or build equipment) can enrich it. I don't know the details, but they probably use a fairly standard process of melting the metal and impurities, then using a centrifuge to separate lighter from heavier.


I did not meant that terrorists will build an atomic bomb (there are cheaper ways to scare and kill people (dirty bomb)), but that nuclear reactors are highly profilic targets for terrorists (dirty bomb for free), so they are in need of special protection.

"Dirty bombs" are not effective weapons. All the building materials in cities would tend to shield against radiation. An atomic bomb is far more effective, but takes more resources to build. An H-Bomb is all but impossible for a terrorist to build.

And while we're at it, let's discuss the consequences as well. A one-in-a-million chance is small, but if it destroys the entire earth, it's probably too risky to offset almost any benefit.

*cough* *choke* *gag*

I can't believe I've got another one of you people. We're not even talking about a nuclear pile/reactor! We're talking about stuff similar to what's in your BACKYARD!

Did you know that plutonium gives off Alpha radiation?

Did you know that Alpha radiation is not in any way shape or form dangerous unless lodged inside your body?

Did you know that Alpha radiation can be shielded by a sheet of paper?

Did you know that dead skin cells are thicker than a sheet of paper?

Did you know that plutonium can burn?

Did you know that when plutonium burns, it forms Plutonium Oxide?

Did you know that Plutonium burning is no more dangerous than magnesium burning? In fact the results are very similar.

Did you know that you have been brainwashed into thinking that nuclear power can destroy the world?

Did you know that if every Hydrogen, Neutron, and Atomic bomb were detonated, it wouldn't even penetrate the earth's crust?

Did you know that nuclear reactors exist that put out only about 6 MegaWatts? In comparison, the smallest coal plants puts out about 30 megawatts.

Did you know that the laws of physics say that 6 megawatts of destructive force is the same whether it's 6 megawatts of coal, nuclear, oil, or dynamite power?

Did you know that more radiation is put out by a single coal burning plant than all the nuclear plants in the US? (Coal contains uranium)

Did you know that the average home consumes about 13 megawatts hours of power per year?

Did you know that Chernobyl has 4 nuclear reactors, three of which continued to operate after the disaster?

Did you know that Russia TRIED to get Chernobyl to blow in order to perform safety tests?

Did you know that only 40 people on site died in Chernobyl?

Did you know that Chernobyl was a stolen US design that was decommissioned in favor of safer designs?

Did you know that Russia did very little to clean up the waste that was expelled and as a result killed about 200 more people through inaction?

Don't take the environmentalists at face value. Do some research for yourself. Oh, and the odds of the RTG not surviving are about the same as the black box in an airplane not surviving.

And, "nuke" power cells are not politically popular due to possible launch crash risks.

While I generally agree with the rest of what you say, please don't call RTGs "nukes". They're simply heavy metals that emit some radiation and really don't post a threat to anyone. Heck, you've probably got similar materials in your backyard. But we're *never* going to convince people otherwise if we don't stop calling them "nukes".

Also, the plutonium doesn't have to be inside you, you just need to be exposed to the gamma radiation released from it to give you cancer.

External plutonium particles are not a serious source of gamma radiation. Unless you're standing directly on top of a reasonably large chunk of plutonium, you're unlikely to get any higher dosage than you would from cosmic gamma rays or building materials such as granite.

However, just because meteriods that release radioactive material into the atmosphere are naturally occuring doesn't mean they are harmless. Natural sources of radiation can give you cancer just as easy as man-made ones

What's your point? Radiation is a fact of life. You're exposed to plenty of it just by living. The trick is that your body is capable of repairing the damage caused by minor amounts of it (up to 100 REMs IIRC). Beyond that threshold, the radiation begins to damage more than your body can detect and repair. Thus cancerous cells may set in. Still, you'd have a hard time getting more than 100 REMs even from 10 pounds of unshielded plutonium. The radiation falls off at the same rate as light (dosage is inversely proportional to the distance).

Another interesting property is that standard building materials appear to be quite good at containing radiation. So much so, that homes and apartments exist where the radiation present inside is *significantly higher* than radiation present outside. A relative of mine actually has an apartment like this in Russia. There are also well known Uranium deposits here in the US that we built cities on top of. (Oops.) Many homes in those areas exhibit this sort of behavior. In fact, your own backyard probably has a nice deposit of Uranium.

I understood that plutonium and other fissile materials give off neutrons as well, which makes other chemical elements turn into radioactive isotopes.

Only when they fission. Plutonium and other radioisotopes do tend to spontaneously fission. But it isn't very often, and there is very few (count 'em on one hand) neutrons released. You'd have to build a nuclear pile with a proper moderator for slowing neutrons to get any serious amount of neutron radiation going. Overall, you probably won't get a higher dose of neutron radiation from plutonium than you would from the uranium in your backyard.

What comes out of these reactors is much less radioactive, for a much shorter period of time.

Are you suggesting that yellowcake (uranium ore) is in any way comparable to this stuff? Are you trolling?