In Part Deux of my ABC Radio National spree on nuclear power, I spoke with The Science Show presenter Robyn Williams. This interview was actually recorded a few weeks before my Counterpoint gig, live with Robyn when he was visiting Adelaide, but it was ultimately scheduled to run afterwards. It was a thrill to get a run on this great programme — it’s my favourite weekly radio slot, and Robyn’s a really switched on kinda guy (if you want to hear me talking on The Science Show a few years ago about two totally different topics, listen here and here).
The slant was this time focused on the history of nuclear power deployment, and the many benefits of 4th Generation Nuclear Power, epitomised by (but by no means exclusive to, ye Thorium buffs), the Integral Fast Reactor.
Below is the transcript of the interview, broadcast on 18 July, and a link to the original .MP3 audio of the broadcast. As with the previous interview, I’d be interested in any feedback. Note that there was one error I made, three times, in the audio, which I have corrected on the transcript — see if you can pick it. I put it down to Gremlins dancing in my head, because I really do know the difference between “x“ and “y” and have never made that slip when writing here — at least as far as I’m aware.
Barry Brook traces the history of nuclear power. Today, about 440 nuclear power reactors are in use, known as Generation 2 reactors. These were designed between 1960 and 1980. Recently, Generation 3 reactors have adopted a standard design, allowing for faster approval. 45 are being built. 350 are planned. Chernobyl was a cheap design. There was no containment building. Barry Brook describes Chernobyl as an accident waiting to happen. Newer reactors are orders of magnitude safer than the older models. Generation 4 is the new excitement. Efficiency is much higher meaning uranium supplies will last so much longer. They can burn a range of isotopes of uranium and other elements producing short-lived waste.
Download audio (ABC Radio National, The Science Show, 18 July 2009)
Robyn Williams: The nuclear power stations some of us grew up with are now over 50 years old. The next, the fourth generation, represents a whole new prospect, one which may have influenced environment minister Peter Garrett with his go-ahead for another uranium mine this week. Here’s Professor Barry Brook with a brief history of nukes.
Barry Brook: Well, the very first generation, I guess you’d call generation zero, was Fermi’s graphite pile under the basketball court in Chicago as part of the Manhattan Project to develop the atomic bomb during WWII. And from that technology spun out the reactor program for US submarines, and so there was a big push by Admiral Rickover to develop the pressurised water reactor for US submarines. Then they basically took a submarine reactor and put it on land in Shippingport and it was the generation one nuclear reactor. And then they built one in Calder Hall in the UK…
Robyn Williams: Calder Hall in the north, that’s right. I remember that was opened over 50 years ago.
Barry Brook: Yes, that was in the early ’50s, about 1952 Calder Hall was opened. From that then it was a rapid phase of research and development and refining the technology. From the 1960s through to the 1980s is generally what’s called generation two nuclear power, and that involves a whole raft of different designs. Most of the nuclear power that’s delivering today…so there’s about 440 reactors delivering today and all of them use water as a moderator and a coolant, and so they’re called light water reactors. They can either be pressurised water reactors or boiling water reactors, but they’re the same fundamental technology.
Recently, in what’s being called an evolutionary advance in nuclear power, there are these generation three nuclear reactors, and they’re basically like generation two but they’re less costly, they’re more modular, you can build a lot of the components in a factory. Importantly there’s a standardised design that they’re trying to develop, which means you can get certification for just one design and then plonk it down in many different places without having to seek independent certification in every new reactor, which was a big stumbling block, especially in the US, in the 1970s. China, for instance, is building 12 nuclear power plants right now, all of the same model, called the AP-1000, which is one of those generation three units developed by Westinghouse.
So that’s the thing that’s happening right now, and I think there’s about 45 nuclear power plants under construction, about 350-odd in planning stages around the world, so that’s taking off. But that’s still basically the nuclear power that everyone thinks about. It is certainly much safer technology than those earlier reactors and certainly the reactor that had a steam explosion and a graphite fire in Chernobyl was a funny sort of Russian design, was very cheap to make, didn’t have a containment building, would never be built in a western country. Essentially as an accident it was, whilst appalling, just can’t happen in any western reactor.
But even from there the design safety has gone orders of magnitude further. And so the most recent model developed by General Electric Hitachi called the Economic and Simplified Boiling Water Reactor had a thorough risk assessment done on it and they estimated the chance of a Three Mile Island style meltdown (which was that accident that happened in Pennsylvania in 1979, it didn’t kill anyone but it wrecked the reactor) about once every 29 million reactor years for these new designs, so that’s a pretty unlikely prospect.
Robyn Williams: But these ones because they’ve really got built-in safety, they’re really carefully designed and so on, they’re really expensive, aren’t they. They take a long time to put up and cost a fortune, so that’s why so many people are reluctant (even the Americans) to put them up.
Barry Brook: That’s the popular opinion, that they’re very expensive, but most of the expense in the US comes from the complicated certification rules right now. Japan, for instance, is building a lot of nuclear reactors and in the late ’90s they built two advanced boiling water reactors which were one of these first of the generation three design, and they built them for a cost of less than $2,000 a kilowatt installed, which is highly competitive. Coal, you might bring it in at $1,500 a kilowatt installed, so it’s very close to that sort of price range.
Similarly, the AP-1000s, the whole idea is that you have the standardised, modularised designs. A lot of the components can be factory built, they’ve been simplified in many ways, inherently safe in that their safety systems rely on the basic laws of physics to shut them down, so it’s often called walk-away safety. There’s so many redundant back-up systems and physical systems that need to fail and essentially can’t fail unless Newton and Einstein are wrong, that they’re inherently safe. So I think the costs of nuclear power are vastly overplayed in the argument about whether we should take it up.
Robyn Williams: What about generation four, using up some of the old waste?
Barry Brook: Yes, generation four is a big excitement I think in nuclear power, and that is often called a revolutionary design. So generation three is evolutionary, the same sort of technology just done better. Generation four looks at it in a completely different way, although ironically most of the technology for it has been developed quite consistently over the last 50 years. The very first experimental reactors used a system called a fast spectrum, to have really fast neutrons that could break up not just what we think of as enriched uranium, uranium-235, but also uranium-238, depleted uranium. So instead of getting less than 1% of the energy out of uranium, these fast reactors get about 99.8% of the energy out of it which means they’re incredibly more efficient in terms of using the uranium resource. And actually we’ve mined enough uranium already to run the whole world in these reactors for about 500 years.
Robyn Williams: So the old argument about running out of uranium isn’t on any more?
Barry Brook: We may run out in 50,000 or so years if we powered the whole world by uranium, but then we’ve got about four times as much thorium to use as well. So the argument that we’ll run out of uranium is a dead duck.
Robyn Williams: And what about using the old waste stuff that we’ve got stored away?
Barry Brook: That’s the really exciting prospect, that these fourth generation reactors, because they can burn all sorts of transuranics, so not just uranium but plutonium and americium and curium, and they can burn the fertile isotopes as well as the fissile isotopes, so they can burn uranium-238. It means that what is generally considered spent fuel, which is about 1% plutonium, about 98% uranium and a bunch of transuranics, all of that can be burnt in these reactors. So something that would have to be stored for around 100,000 years because of their long half-lives (plutonium is 24,500 years, for instance, it can take quite a while to decay) these can all be consumed in these reactors, generate electricity and then the fission products, the result of smashing these large atoms into smaller ones, highly radioactive which is a good thing actually because it means that their half-lives are very short and within less than 300 years they’re below the radioactive level of the original uranium ore. So all of the fuel that’s currently being produced by the current generation of light water reactors will go into fast reactors and be totally consumed. So there is no long-lived radioactive waste problem.
Robyn Williams: But 300 years is more than my lifetime and it’s still going to be around. Doesn’t that worry you a bit?
Barry Brook: It produces about a tenth the waste of the current generation reactors, so it’s a very small amount of waste. It comes in a vitrified form which is a type of rocky glass that locks up these fission products for about 1,000 years.
Robyn Williams: Like synroc?
Barry Brook: Very similar to synroc. And of course 1,000 years if you’ve got to wait 100,000 years isn’t sufficient, but if you’ve only got to wait 300 years then that’s fine. So we’ve built places like Yucca Mountain. We’ll need geological storage areas for this waste, but managing it for 300 years is clearly not a problem. We’ve managed many structures built by humans for 300 years, and it will be about a tenth of the waste, and frankly it’s also the only possible solution for getting rid of that long-lived waste. And so I think for all of the huge benefits that using this sort of power source brings, the small cost of storing about a tenth the amount of waste that comes out of current reactors is a tiny price to pay.
Robyn Williams: How much do they cost and how long does it take to put them up?
Barry Brook: That’s a question that can only really be answered by building a commercial scale demonstration. The Russians are building a reactor called the BN-800 right now, which is a sodium cooled fast reactor, it’s one of these generation four reactors, currently under construction. The Chinese are looking at building one too. The Indians are building a fast breeder reactor. So we’ll know within the next couple of years about how much they cost and about how quickly they can be built.
General Electric Hitachi, one of the major world producers of nuclear power stations, has got a model blueprint called the S-PRISM which is one of these integral fast reactors that they say can be built for about $1,500 per kilowatt installed, which is extremely competitive. And the design of these plants is such that they’re very modular. Each reactor is about 300 megawatts, and so you might have them in double loops and about four of these reactor loops within a plant, so a total plant of about 2.5 gigawatts, which is considerably larger than any coal-fired power station. The economics of doing it that way means that most of it can be built in a factory and then brought on to site, and so that reduces costs. You can actually build them on sites where coal-fired power stations currently are. Even in some cases there’s the prospect of ripping out the coal burner and whacking in one of these fast reactors. And frankly if we’re going to replace the 500-plus gigawatts that are being built in China right now and that have been built in the last ten years, all of that coal that we’ve got to shut down, I see this as being by far the best most economic prospect of convincing China to do that.
Robyn Williams: Barry Brook, who is the Sir Hubert Wilkins Professor of Climate Change at the University of Adelaide, Wilkins a legendary explorer. The fourth generation of nuclear power, perhaps that why Peter Garrett gave the nod to another Australian uranium mine this week.