Uranium Pebbles May Light the Way

kristy_christie writes "According to Wired News, South Africa's state-run utility giant Eskom and its international partners want to build the world's first commercial 'pebble bed' reactor, which, instead of using fuel rods, 'is packed with tennis ball-size graphite "pebbles," each containing thousands of tiny uranium dioxide particles'. To developers, the Pebble Bed Modular Reactor promises a rebirth of nuclear energy. Proponents insist that the reactor's design features make it 'meltdown-proof' and 'walk-away safe'."

Comments

Sweet

[__aavhli5779]

I applaud this kind of work.

Nuclear Power, despite the cries of environmentalists, is possibly the cleanest mass power source. On a scale of power generated per ton of input material it is incredibly efficient (bested only by those power sources which require no nonrenewable input, like wind/tidal/etc.), generates no effluent or air pollution, and needs only a competent staff (and, unfortunately, security), to stay running properly.

Nuclear plants may be prohibitively expensive to build these days, but if "pebble bed" reactors cost significantly less, then they may lead the way back towards what I view as our ideal energy source.

It's time to give nuclear a second chance.

Re:Sweet

[gl4ss]

the problem that most people have with nuclear power is tchernobyl(or similar catastrophy that would release radioactivity to a wide area).

'most people' don't know even the basics of how the energy is generated, all they know is that the place can explode and then there's going to be 3eyed fishes. the problem is that even if it's a 'failsafe'(won't explode) plant there's going to be hell explaining it to the people who are against nuclear power for mainly emonational reasons(and assume that people defend nuclear power for similar reasons because they hate the environment or something silly like that, or just for pure greed).

it's like that old joke... "what we need nuclear power for? i only need electricity"(dunno how the variation goes in english actually, but you get the idea).

around here there's a need for another reactor(industry needs the juice) but there's quite many people who are against it, yet they don't complain when we need to buy the same amount of electricity from russia(that is generated by nuclear reactor there, just over the border, at lower safety standards than what would be in place if the reactor were on our side of the border).

Re:Sweet

[Glock27]

Two words: Nuclear waste.

Two words: Lung Cancer.

That is the alternative, and pollution from traditional power generation plants is killing people every day, and sickening many more.

There is not a single permanent disposal site world-wide. no one can guarantee the safety. the U.S. government even has a website on _just this problem_. Ready-made dirty bombs are driven in trucks all over the country. GREAT IDEA.

If someone wants to kill a lot of civilians, all they need is a garage lab to produce chemical or bio agents. Much more effective, much easier to deal with, even more scary (1 gram of the right bio agent could kill millions). See the recent research on mouse pox for some really scary stuff (did that story make /.?). How 'bout a bio agent that'll only wipe out one ethnic group? The research is just about there. It is always hard to evaluate relative risk, but to me nuke power is way down the list.

BTW, as far as nuke disposal, there's a good reason for a lunar colony... =) Name another major energy source where the pollution could realistically be taken entirely off-planet.

Also BTW, I hope some of the recent solar energy developments lead (finally) to competitive photovoltaic power generation on a distributed basis (that'll tick off the power companies!). One of the more exciting developments is solar fabric, which can be used in curved building designs.

Re:Sweet

[Aglassis]

You said: "The history of nuclear power so far, however, doesn't leave one optimistic."

What metric are you using to say that nuclear power has historically been unsafe? The number of deaths caused per MWh produced? Deaths or injuries per reactor-hour of operation? Average deaths per year at a given plant?

Really, compare these metrics to that of any other power distribution plant and you will see historically, even with the huge publicized disasters like Chernobyl and TMI, that no other large scale power producer even compares in safety to nuclear power.

But since we're on the topic of nuclear power safety history, the website The History of Nuclear Power Safety is an excellent resource.

Re:Sweet

[sql*kitten]

Even if you make it relatively "meltdown-safe", you still have huge issues as to what to do with the waste. The plutonium generated by the reactor described has to be stored for thousands of years, guarded against terrorist use. That is a massive hidden future cost, financial & risk-wise.

That is a myth spread by the anti-nuclear lobby, who are really anti-industry, as a side-effect of being anti-capitalist. Think about it logically for a minute. Why is spent fuel dangerous? Because it emits radiation. What is radiation? It is energy. What is the point of any fuel? That you can extract energy from it.

The problem of what to do with nuclear waste has already been solved: just loaded it into another type of reactor (called a "fast breeder reactor") and continue to use it. Nuclear waste simply is not a significant reason not to use nuclear power. The only problem is what to do with old, worn-out reactors.

Meltdown isn't the (whole) problem

[Tim C]

It's how to handle the waste. That represents a real engineering challenge - some of that stuff is going to remain toxic for tens of thousands of years. Not only does it have to be stored safely and securely, but you have to work out some way of marking it so that should anyone stumble across it in a couple of thousand years, they understand not to touch it. The amount languages and cultures change, you can't just write on it, and even things like skull pictures could be interpreted as meaning "burial chamber - archaelogists, get digging!".

That said, I'm not against nuclear power (from fusion) per se. Of the options we have, it's one of the best at the moment. "Alternative" power sources need a lot more work, and fusion, whilst extrememly promising, just isn't practicable yet (unless I've missed a major breakthrough in the last couple of years). I'm just pointing out that there are still other problems that need to be addressed.

Re:Meltdown isn't the (whole) problem

[Znork]

The solution to that is simple. You make new fuel of the waste. The technology to do it already exists, so instead of using a miniscule amount of the fuel and then considering it 'spent' and trying to store that highly radioactive material you can run it through a breeder reactor and use it again. And again. And again. And again.

That way you dont get a lot of waste, and you get many many times more use out of the fuel you have.

Nuclear waste is a problem that already has a solution, and a solution that is ecologically sound and very much in line with recycling and reuse.

-1 Flamebait

[Dancin_Santa]

Reading some of the comments in this article, I have to wonder when 'Geek' and 'Nerd' transformed into 'Reactionary Luddite'.

Re:Decomissioning and waste management?

[mlyle]

Guess what? The enriched uranium they use in reactors contains in the region of 3% to 4% U-235 - making it litterary too hot to handle. Even 'spendt' reacorfuel contains more U-235 than ordinary oranium-ore, as well as more than a bit of Pu-239 and Pu-240 (the longer the fuel stays in the reacor, the more Pu-240). And Pu-239 and Pu-240 is two isotopes of an element better known as plutonium... granted, it's not weapongrade plutonium, but it's still something I wouldn't have scattered about.


Sure, we "enrich" the uranium-- largely by sorting isotopes. There's no reason why you couldn't choose to de-enrich/deplete the uranium back down for storage, if you thought this was beneficial. This is why it's entombed in glass in many storage proposals, and why it's often reprocessed-- so you can sort the "useful fuel to reuse" and "spent fuel/waste".

There are intermediate-term (80-500 year) storage problems involved with the high level wastes produced in fission reactors. The thing is, these wastes inherently have short half lives and decay to more harmless stuff very quickly.

Chernobyl was stupid

[cr0z01d]

Chernobyl had a lot of things that were just wrong.

The reactor increased in efficiency as temperature increased. This is a nice little feedback loop. Most reactors lose efficiency as temperature increases, meaning that it is difficult to try and overload the reactor, even on purpose.

The reactor was designed to be cheap, and it did not have a dome. Domes contain radioactive material very well. Tests have shown that an aircraft hitting a dome would hardly scratch it.

As another cost-cutting measure, the reactor didn't have any good backup power. It may seem silly to have a power plant that needs power, but nuclear power plants do need power to start up and in case of emergencies. Western plants have batteries and generators.

As if these technological blunders weren't enough, some bonehead transfered control of the power plants from the ministry that designed and built them, where all the trained personnel are employed, to the ministry of energy. There are reports of operators sitting on the control board and people showing up to work drunk.

Basically, in 1986, the Chernobyl reactor demonstrated a bunch of "don'ts" to a world that should have already known.

There will always be technology out there that can be misused. The amount of that technology will only increase. Do we ban knives because people get stabbed? Do we ban nuclear power because a couple of Russians cut costs?

The 'ball' nuclear reactors are basically foolproof. You put a bunch of balls next to each other and you get heat. This is not weapons grade Uranium.

I only see one problem with nuclear -- the small amount of waste that is generated needs to be handled properly. It can be done, but it just has to be done right.

Re:Decomissioning and waste management?

[TamMan2000]

Fact: There is little or no pollution from an operative reacor.

Fact: Spent fuelrods from reactors are a major enviromental problem.

Fact: The byproducts of all other currently viable forms of energy production are major environmental problems.

I can't think of anyone who would say that nuclear waste is not bad. But I for one, and many others who have researched the topic, believe it is less bad than the alternatives.

I would rather have a small amount of really bad stuff being controled, than a huge amount of pretty bad stuff being spewed into the air I breath every day.

Re:Partly true...

[Martin Blank]

Most of the re-use part of nuclear fuel is, as I understand it, prohibited by government regulation, something having to do with plutonium generation. My understanding of a possible use involving breeder reactors, though, involves using the plutonium's natural decay to enrich uranium fuel, allowing the plutonium to break down into less harmful byproducts while the uranium is enriched for fuel in the near future. This seems a more complete use of the fuel to me, and could result in less hazardous waste.

However, use of plutonium is rather taboo for some reason -- witness the furor over Cassini's radioisotope generator, which some environmentalists claimed could kill thousands in the event of an accident on launch in 1997 or during the flyby of Earth in 1999, with one site suggesting a 10-micron particle could result in the exposure of a person inhaling it to thousands of REMs. Their argument was that the release of the 72 pounds of plutonium would be catastrophic over centuries.

An article in a 1993 Oak Ridge National Laboratories Review states, "according to NCRP Reports No. 92 and No. 95, population exposure from operation of 1000-MWe nuclear and coal-fired power plants amounts to 490 person-rem/year for coal plants and 4.8 person-rem/year for nuclear plants. ... For the complete nuclear fuel cycle, from mining to reactor operation to waste disposal, the radiation dose is cited as 136 person-rem/year; the equivalent dose for coal use, from mining to power plant operation to waste disposal, is not listed in this report and is probably unknown."

Even factoring in mining -- where radioactive dust presumably goes into the air -- and disposal -- where various bits of radioactive dust and water are released -- nuclear plants produced only about a quarter of the average radiation dosage that coal plants do over their lives. I've seen the strip mines that are used to get at uranium, and while it's not pretty, it's not nearly as bad as the destruction of entire mountains in the Appalachians. There is also research going into extracting uranium from seawater for about $120 per pound, which, although about 10 times the current rate, could be more environmentally safe and could provide thousands of years of power, presuming we operated on nuclear power for that length of time.

I'm all for nuclear energy. While I am also a proponent of renewable sources, I don't like the environmental damage caused by hydroelectric. Solar has issues of night-time electricity use, and it is reportedly a messy thing to make, with some pretty dangerous chemicals involved, not including any batteries that would be needed for cloudy days and night use. Wind has issues of reliability, and tidal generators have a range issue, not to mention that I wonder how it would affect the beaches to have thousands of them operating.

I recognize the dangers of nuclear energy. I know that it's hard to clean up, and that there are significant security risks; I'd much rather be in a room with an exposed piece of coal than an exposed piece of reactor-grade uranium. But that piece of uranium will be useful long after the ash from the coal has been carted off and buried. It will have given off no CO2 or nitrogen or sulfur oxides during its use (save whatever transportation is used for it), and less radioactivity.

In balance, I believe that nuclear reactors are a far better source of energy than anything else we have at the moment.