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'."
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.
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.
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.
... 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."
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.
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.
You can never go home again... but I guess you can shop there.