Boilers, Nuclear

After Japan

Issue 4 and Volume 115.

By David Wagman, Chief Editor

Japan’s nuclear crisis should not end the era of nuclear power generation. Its lessons, however, must be thoroughly understood.

In the first moments after the earthquake, it appears that reactors across Japan successfully inserted control rods into their cores, ending the reactions. Here the technology worked well. It was after the reactors came offline that systems began to fail.

The primary culprits seem to be electromechanical in nature: the pumps, valves and related controls have been at the core of all steam power generation units for well over 100 years and serve as the heart of such units, pumping fluids to control, distribute and regulate heat. Shaken by one of recorded history’s most powerful earthquakes and battered by a tsunami, these systems—along with various backup and fail-safe systems—failed in at least two instances, precipitating Japan’s nuclear crisis.

Many have said the nuclear industry could not afford another accident on the scale of Chernobyl or even less. The scenario that began unfolding March 11 had seemed so unlikely days before. But Japan itself is the product of tectonic action and most of its nuclear power plants line the coasts. In 2007, the world’s largest nuclear power plant—the seven-unit Kashiwazaki-Kariwa station—suffered minor earthquake damage and was offline for 22 months as operators and regulators scrutinized the extent of the damage. The world’s nuclear industry dodged that bullet in 2007. It was not nearly so lucky in 2011.

Headlines and live video from Japan make it easy to write off nuclear power. But in the U.S. the technology has enjoyed a remarkable turnaround following the 1979 Three Mile Island accident. The industry created the Institute of Nuclear Power Operations following that accident to improve and standardize training and operations across the nation’s 104 operating nuclear units. Since then, nuclear power has been a consistently reliable—and with few exceptions—safe electricity generator.

And yet I return to comments made to me last year by two MIT-educated entrepreneurs who are working to develop new processes to manufacture photovoltaic cells. Emanuel Sachs and Frank van Mierlo clearly have skin in the game to ensure the success of their solar energy-focused company, 1366 Technologies. But in an interview as the Deepwater Horizon crisis in the Gulf of Mexico was unfolding, they spoke of the inherent risk of complex technology. Systems fail, bad things happen all the time. With some technology—and here they spoke of nuclear power rather than the spill in the Gulf—the consequences of failure can be enormous. We are learning that lesson once again from Japan.

Still, we must acknowledge that the nuclear industry—whose technology today is, after all, largely Japanese technology—saw the flaws in overly complicated safety systems and designed Generation III+ power plants to incorporate systems that rely far less on electromechanical devices when something goes terribly wrong. Plants incorporating those very features are being built in China right now and are what U.S. utilities plan to build, along with power generators in India, Korea and Japan.

Bear in mind that more than 60 older-generation nuclear power units have won license extensions from the NRC. Extending the lives of the existing fleet means we will be deprived of much better safety technology for years to come.

Call it irony, but two days before the Japanese crisis, the NRC delayed for 18 months a decision on Mitsubishi’s reactor design for the U.S. market to consider how a design change might affect the unit’s performance in an earthquake. The delay affects the timing of proposed units by Dominion and Luminant.

Nuclear power is not without risk; we have always known that and Japan more so than any other country. But with the exception of the four Diablo Canyon and San Onofre units in California, no U.S. nuclear station is located near both an active geologic fault and a tsunami-capable body of water. In light of Japan’s crisis the global nuclear industry must consider worst-possible scenarios and then design and build with those consequences in mind, plus an additional measure of safety. Whether or not new nuclear power plants are even insurable remains to be seen; risk calculations no doubt are being scrutinized by underwriters shaken—quite literally—by sizeable quakes in Chile, New Zealand and now Japan.

Nuclear power remains among the world’s best sources of baseload, largely emission-free electricity. It can and should continue to play a major role in efforts to provide reliable and virtually carbon-free power.

In the final analysis, a future that contemplates nuclear as a major source of baseload generation complemented by small-scale and geographically dispersed renewables still holds much promise for electric power generation.

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