DALLAS—It can't happen here. Or can it?

Many reactors in the U.S. have a similar design to the General Electric units that are spewing radioactive clouds into Japan's skies and keeping the world on edge. So, the U.S. should learn lessons from that ongoing disaster and seriously consider retrofitting at least some of its reactors, Raymond L. Orbach, former undersecretary for science at the U.S. Department of Energy, said here this week at a meeting of the American Physical Society.

"We're trying to learn from Fukushima," said Orbach, who now directs the University of Texas at Austin's Energy Institute.

Orbach and other physicists warned about the current "hysteria"—caused in part by human errors and a lack of transparency on the part of plant owner Tokyo Electric Power Company—and the possible consequences of abandoning nuclear power, such as the environmental impact that would result from producing the same electricity with fossil fuels. Instead, more research and better engineering are called for, he says, adding: "I'm hopeful that cooler heads, wiser heads, will prevail."

Nuclear engineers have long promoted intrinsic safety features that could make future reactors safer, but retrofits at existing nuclear power plants could make intrinsic safety features available at old reactors, too, Orbach said. Such improvements would particularly pertain at 23 reactors in the U.S. that are based on the same 1970s General Electric design as the Fukushima reactors.

For example, one of the worst scenarios at Fukushima would be the release of radioactive material not from the reactor itself but from the pools of water where "spent" fuel is kept. Spent fuel still produces copious heat from its ongoing radioactivity. A failure to refill water lost to evaporation or, worse, from a leak, could lead to a complete boil-off and large releases of radioactive materials into the atmosphere. "They need to figure out a way so that if water level drops, you inject new coolant passively," without the need for pumping, Orbach later told Scientific American in an interview.

Passive cooling systems could be powered by the very heat produced by the spent fuel. Upgrading nuclear plants is expensive, Orbach admitted in his talk, but these plants have long ago paid for themselves and are now producing electricity at a very low cost, which would "seem to have a bit of headroom" for paying for retrofits.

Scott Burnell, a spokesman for the Nuclear Regulatory Commission, says that Mark I reactors have had repeated safety retrofits over the decades, and in particular since 9/11. After the attacks in 2001, "all U.S. plants have incorporated additional resources and procedures to compensate for the possible loss of large areas of the plant due to fires and explosions—these mitigative measures include actions to ensure spent fuel pools are kept cool."

Orbach also called for increased funding for nuclear power research. In a separate presentation here, Robert Rosner, an astrophysicist at the University of Chicago and the former head of the Argonne National Laboratory, pointed out that funding for nuclear energy research precipitously declined between the late 1970s and the late 1990s and has not recovered much since then.

Orbach and Rosner spoke here at a session on nuclear power that had been scheduled long before the world woke up to the new threat at Fukushima Daiichi. With the nuclear crisis still unfolding, the physicists tailored their talks to address issues raised by the crisis in Japan and a predictably renewed wave of public skepticism toward nuclear power.

Rosner cited several arguments in favor of nuclear power. If the U.S. abandoned nuclear power, the nation might end up forfeiting economic opportunities in an industry dominated by a handful of companies that are now reaping profits around the world.

Nuclear energy also provides energy security and diversity with a source that is largely insensitive to fuel price fluctuations and thus to market shocks. "Even if you're anti-nuke," Rosner said, "you might want to think twice about completely abandoning nuclear."

In the absence of any tax on carbon emissions, however, it is hard for nuclear to compete with coal and gas, and therefore "it's very difficult to make economic case for it."