What's Missing from the Nuclear Power Debate?

Ah, you optimistic soul. Did you really think the nuclear power debate died after Three Mile Island brought the reality of its dangers home to insurers, investors and utility companies?

Think again. As both the rhetoric and the reality of global warming heat up in the years ahead, nuclear power is about to rise from the grave like a reanimated zombie. And the bad news is: It looks like we're going to have a harder and harder time escaping some very brain-dead discussion about it.

There's danger here—but it's not what you probably think it is. As the new battle lines are being drawn, we're at serious risk of having the wrong conversation—and, perhaps, fighting the wrong battles as a result. Americans on both sides of the issue are already positioning themselves take up the same positions they abandoned in the early 1990s, with one side presenting the same old technology solutions and the other side countering with the same old arguments. Neither side seems to be even remotely aware of emerging second-generation nuclear technologies, all of which are being developed overseas, that pretty much render every argument on either side absolutely wrong.

This week, I'd like to take a quick look at where nuclear power is headed, and why we might want to keep an open mind about it in the future. That said, I'd like to make a couple of things clear. First, I am in no way suggesting that old-fashioned first-generation nuclear reactors have any place at all in a carbon-free future. We've been there, done that, got the Chernobyl and TMI tee-shirts and the glow-in-the-dark three-eyed frogs. Nobody—not even Wall Street— wants to go back there.

Second, I'm not even convinced personally that second-gen nukes will, in the end, live up to their initial billing. (Few things ever do.) But they are different enough that we need to take them on their own terms. That means keeping our minds open to the new possibilities they might offer. It also means that arguing them down using the same old talking points is only going to make it easy for the industry to portray us as out-of-date and irrational—and probably deservedly so.

So: if we're going to have this conversation again, we need to have it on the basis of the facts as they are in 2008, and not as we recall them being in 1988. Unless you've been paying unusually close attention the past few years, when it comes to the future of nukes, it's quite possible that everything you think you know is wrong.

Not Your Father's Nukes

The game-changing technology is the pebble-bed reactor [2]. They're actually a very old reactor design, predating the rod-based designs that eventually prevailed because Admiral Hyman Rickover chose that design for America's nuclear sub fleet —thus committing the country to what was, even then, a particularly dirty and dangerous form of reactor. But they're on their way back now —especially in South Africa, where PBMR [3] plans to have a fully-operational prototype reactor on line within the next year or two; and China [4], which is pouring more funding into pebble-bed research than any other nation, and also has its first reactor in the works. Both countries consider PBRs a critical investment in exportable technology for the future.

The "pebbles" in pebble-bed reactors have a core filled with tiny sand-like granules of fissible material. A pea-sized pile of these grains is encased in four layers of specialized ceramics and graphite until the entire unit is the size of a tennis ball. The shell keeps most of the radioactivity inside: you don't want to walk around with a pebble in your backpack, but they can be safely handled by people in standard radioactive hazmat suits. About 360,000 pebbles are stacked up in the reactor core, creating a hot pile. Helium is circulated around the pebbles, conveying the heat to the turbines.

It's a very simple design, and one that offers a multitude of advantages:

Safety: PBRs operate at temperatures of about 1,500 degrees—nothing remotely close to the surface-of-the-sun heat generated by rod-based reactors. If it gets too hot, the reaction stops naturally, with no human intervention. This makes meltdowns impossible.

An early PBR experiment in Germany did result in an atmospheric radiation release in 1988 (which pretty much put an end to that country's research into PBRs). The accident was due to a pebble that got caught and crushed in machinery—a problem that should be fixable in future designs.

Other safety concerns include the lack of a containment building (which allows for air cooling), which could leave the reactor more exposed to terrorism; and possible failures of a pebble's ceramic outer coating, which could allow the inner graphite shell to burn. Again, these are problems that may yield to further research. It should go without saying that PBRs shouldn't be part of our carbon-free energy solution unless problems like these can be definitively resolved.

Expense: Their safety makes PBRs vastly cheaper to build, since they don't require the extreme level of containment and fail-safe equipment of traditional reactors. Furthermore, they're designed to be modular —small enough that an average town can afford to buy a little one, then add another and another over time as demand grows.

Efficiency: One of the strongest criticisms of traditional nukes is that we're likely to run out of uranium not too long after we run out of oil. Current PBRs are many times more efficient at turning radiation into electricity, which means we could stretch the current known 80-year supply [5] for several centuries—or more, as the technology matures and even more efficient reactors are perfected.

Sole-Sourcing Risks: Current PBR designs can run on a variety of fissible materials, including thorium and plutonium. If the supply of one is disrupted, you simply switch to another.

Spent Fuel Handling: PBRs don't solve this problem entirely—the spent fuel still needs to be stored—but it does make it considerably less complicated and dangerous than the nightmare we've already been through. The graphite composite shells are designed to remain intact for a million years, outlasting even plutonium's radioactive lifespan. Transporting the pebbles, while still a dangerous proposition, carries far more manageable risks: even a bad truck or train accident won't contaminate a large area, and it can be far more thoroughly and reliably cleaned up. (The South African facility at Pelindaba can store 80 years of fuel onsite, which means they won't be moving any for a long, long time.) The volume of the shells means that the pebbles take up about the same amount of storage space per watt generated as current systems—but since most of that volume is graphite and ceramics and the overall radioactivity is vastly lower, it's far, far safer for us, and for future generations.

Nobody wants to generate—let alone transport or store—more nuclear waste. But as the threat of climate change looms, the way we weight that equation may change. (Create a few noxious waste storage sites around the globe, or let the whole planet cook? Hmm. Choices, choices....) Having a safer way to move and store the waste doesn't eliminate the hazard, but it may well change the way we reckon the risks.

Weaponization: One serious problem with spent rods is that they can be recycled into fuel for nuclear weapons. But PBR pebbles' greater efficiency means that the fuel is burned more completely—which means there's not much left to weaponize. Furthermore, it's not worth cracking through the heavy shell just to get at that little bit of fuel. As a result, there's no real incentive for countries to go mucking around in each other's spent fuel depots looking for nuclear weapons fuel.

Desalinization: Fifteen hundred degrees is a convenient temperature for distilling very large quantities of seawater—which means PBRs may become a cheap, simple solution for the world's looming potable water crisis. South Africa's PBMR is rumored to have designed systems that use the waste heat generated by the reactor to distill seawater for city taps.

Cooling: Unlike traditional nukes, PBRs are cooled by helium, not water; so there's no hot water discharge that might disrupt ecosystems in neighboring waterways.

You can see why this technology is intriguing enough to merit a fair look.

The Politics of PBRs

Pebble-bed reactors haven't yet entered the American nuclear conversation for a variety of reasons. One is that it's been experimental technology for the past decade, and we're still a good five years from having anything saleable on the world market. Another, of course, money: Our government, plus quite a few corporations, have invested heavily over the decades in first-generation nukes, and aren't ready to abandon those sunk costs to move over to something new. (However, they're not out of the game entirely: Westinghouse and MIT are among the U.S. companies and research institutions that are participating in the South African and Chinese projects; and the Department of Energy has issued a $3 million grant to kick off home-grown PBR research in Idaho.) Another is the intensely nuke-hostile cultural climate of the past 25 years, which has made it harder to generate R&D funds to explore other kinds of nuclear energy.

A couple of weeks ago, I described a scenario [6] in which the United States is eclipsed by another nation—one that emerges to offer the world an energy regime that's more efficient and versatile than oil was. The prospect of a new Chinese empire rising on pebble-bed reactors is one extremely plausible direction this scenario could take. In a 2004 article in Wired [4], Spencer Reiss notes:

The Future of Nuclear Power, a 2003 study by a blue-ribbon commission headed by former CIA director John Deutch, concludes that by 2050 the PRC could require the equivalent of 200 full-scale nuke plants. A team of Chinese scientists advising the Beijing leadership puts the figure even higher: 300 gigawatts of nuclear output, not much less than the 350 gigawatts produced worldwide today.

Taking the long view, the Chinese are not staking their future on coal and oil. By mid-century, they could well be the world's leader in building and using PBRs. And as I noted in that earlier article, nations that dominate the world's power supply tend to end up dominating the world politically and economically as well.

This is why allowing our nuclear conversation to stay stuck in the '80s is so dangerous. We have a choice: We can re-hash the old arguments based on "facts" that are no longer true; or we can ask our own nuclear industry leaders why they're trying to sell us 60-year-old technology instead of looking ahead more aggressively to see what the next generation of nuclear power might bring us. We can also ask them why they're allowing the Chinese to open such a wide lead in the race to the next energy regime—a lead that may well be decisive in China's eventual emergence as the world's next superpower. At the very least, it makes no sense at all to spend a single dollar building even one more old-style plant when something with so much better potential looms so very near in the future.

As I said: second-generation nuclear power will, no doubt, have problems of its own. (There is no such thing as a free lunch, ever.) Furthermore, there is no question whatsoever that the fastest, best way to cut carbon emissions is by increasing the efficiency of our lifestyles.

But, faced with the increasing likelihood that whatever we do will not in the end be enough, it is wise for us to soberly, critically re-consider the nuclear option. Compared to the old technology, 21st-century nuclear power is such a quantum improvement that it deserves to be explored and discussed on its own terms. And Americans—both environmentalists and nuclear scientists—need to approach that conversation with fresh questions and fresh answers, mindful that those little graphite pebbles may well be the start of a whole new ballgame.