Nuke Energy: The Next Casualty of Japan
The aftershocks from the Japan quake are being felt around the world: Nuclear energy projects are being suspended with knee-jerk swiftness and little thought.
It's like watching a Japanese Monster B-Movie: Battered by two epically-scaled natural disasters and now a human-made emergency in the form of an ongoing nuclear crisis, the only thing missing from the unfolding Japanese scenes, it seems, is the eruption of Mount Fuji and a rubber-suited monster emerging from the summit and rampaging towards Tokyo.
The situation at the stricken Fukushima Daiichi nuclear plant is already factoring into any number of nightmare reports and prognostications, a new and potent Japanese symbol of our collective fears about science. Fukushima is further demonizing -- or monsterizing -- an industry which might actually offer the only clean, sustainable energy source for a world simultaneously preoccupied with Godzilla-sized carbon footprints and climate change.
The 1979 partial reactor core meltdown at Three Mile Island and the 1986 Chernobyl disaster which set the previous benchmark for nuclear annihilation anxieties, served to curtail public and political debate on atomic energy in the United States. Not a single new nuclear power plant has been built here for decades. This unofficial moratorium came about not just because of concerns about the safety of reactor designs and the difficulties associated with disposing of waste material but also as a result of the costs. Astronomical costs.
Second-generation commercial nuclear plants like the one at Fukushima and all of the stations built in the US in the 1960s and '70s pushed the engineering capabilities of the day further than they should have been pushed. They also shoved cost efficiency into the realms of fantasy. Generating electricity at second-generation nuclear plants costs twice what it does to produce power at oil- or coal-fired facilities. In the US as in other countries, only vast state subsidies make existing nuclear power programs possible (this is particularly true of France, dependent for almost 80 percent of its electricity on second-generation plants).
But science has changed markedly in recent years. And so has the safety and cost-effectiveness of nuclear power. In engineering terms, the fourth-generation nuclear plants now being developed are as far removed from their expensive, awkward second-generation progenitors as a B1 bomber is from the second generation of motorized box kites which sputtered over the Western Front during World War One. The technology hasn't so much been refined as re-invented.
New designs must satisfy four essential criteria: no accident, systems failure or human error can set off a technological chain reaction culminating in the release of radioactive material; the uranium used cannot be enriched to weapon grade-level; spent fuel must be easier to dispose of than the current unwieldy and unsafe radioactive rods; and, the costs of producing electricity must be substantially cheaper than those associated with plants using fossil fuels.
There are a number of emerging reactor designs which fall under the fourth-generation umbrella. Graphite-moderated pebble bed reactors, in particular, might one day fulfill nuclear energy's long-held promise of providing virtually unlimited, cheap and clean electrical power. Heating helium gas to temperatures of 900C to power turbines, there's an orders of magnitude difference between the electrical generating efficiency of pebble bed reactors and second-generation water-cooled reactors.
Compact by the standards of today's "Metropolis"-scaled nuclear plant machinery (a pebble bed reactor can fit into a shipping container), a single 200 megawatt device could power a large town. Multiple reactors run from a single site could provide a large city's electrical supply. Enough of them could help countries in the developing world make the leap to fully developed infrastructures without becoming dependent on carbon fuels: aside from meeting their electrical needs, gas-cooled reactors would also be ideal for mass producing the type of hydrogen fuel cells which could power everything from homes to automobiles -- allowing emerging economies to bypass oil and coal just as cell phones have allowed them to bypass land lines.
The technology is not entirely risk-free -- no technology ever is. But as Dr. James Martin, founder of Oxford University's interdisciplinary James Martin 21st Century School, has said, extensive use of fourth-generation nuclear power would be incomparably safer than allowing the public to drive cars.
Prototype pebble bed reactors -- so-called because they use billiard ball-sized and -shaped uranium fuel elements -- are being built to standards which their designers like to call "walk-away safe". In other words, should anything go wrong, the control staff can literally walk off and a system as close to being fail-safe as it's possible to engineer will automatically prevent a meltdown.
At a nerve-jarring 2004 demonstration for journalists, the operators of a small Chinese pebble bed reactor abruptly closed down its coolant system. And then quite literally walked away. At Three Mile Island a minor cooling system malfunction led to the near-catastrophic emergency; Fukishima is providing a real-time case study. When a cooling system failure occurs at a conventional nuclear plant, the fuel rods overheat, radiation levels spike and the nightmarish prospect of a meltdown goes from being a remote theoretical possibility to a distinct probability.
In Beijing, slack-jawed reporters watched as gauges showed the temperature in the pebble-bed reactor soaring to 1600C. Then it began to fall back to normal levels. No human intervention had taken place. None was necessary.
Each of the billiard ball "pebbles" in the reactor contained thousands of tiny, ball bearing-type uranium pellets, each sealed in silicone-carbide shells which serve as individual containment domes of sorts. The pebbles' outer casings provide further protection. The uranium -- just nine percent enriched and impossible to weaponize -- is processed to slow neutron production if the reactor temperature begins to rise, automatically dampening the chain reaction. Pebble bed reactors are, in effect, meltdown-proof.
The fourth-generation technology is still a work in progress. But it's demonstrably no longer a theory-based concept. And it's certainly not an example of mad science as its critics -- ranging from professional eco-warriors to professional lobbyists for the coal and oil industries -- have claimed.
The hysterical aftershocks being produced by the Japanese earthquake are making themselves felt around the world. Nuclear energy programs are being suspended with knee-jerk swiftness and little or no forward thought. If the funding and development of fourth-generation technology is disrupted or even ended, this might prove be the second man-made nuclear disaster to result from last week's tragedy.