The Nuclear Power Plant of the Future May Be Floating Near Russia

MURMANSK, Russia — Along the shore of Kola Bay in the far northwest of Russia lie bases for the country’s nuclear submarines and icebreakers. Low, rocky hills descend to an industrial waterfront of docks, cranes and railway tracks. Out on the bay, submarines have for decades stalked the azure waters, traveling between their port and the ocean depths.

Here, Russia is conducting an experiment with nuclear power, one that backers say is a leading-edge feat of engineering but that critics call reckless.

The country is unveiling a floating nuclear power plant.

Tied to a wharf in the city of Murmansk, the Akademik Lomonosov rocks gently in the waves. The buoyant facility, made of two miniature reactors of a type used previously on submarines, is for now the only one of its kind.

Moscow, while leading the trend, is far from alone in seeing potential in floating nuclear plants. Two state-backed companies in China are building such facilities, and American scientists have drawn up plans of their own. Proponents say they are cheaper, greener and, perhaps counterintuitively, safer. They envision a future when nuclear power stations bob off the coasts of major cities around the world.

“They are light-years ahead of us,” Jacopo Buongiorno, a professor of nuclear engineering at the Massachusetts Institute of Technology, said of the Russian floating power program.

Rosatom, the Russian state nuclear company, has exported nuclear technology for years, selling plants in China, India and a host of developing nations. But smaller reactors effectively placed on floats can be assembled more quickly, be put in a wider range of locations and respond more nimbly to fluctuating supply on power grids that increasingly rely on wind and solar.

The Russian design involves using submarine-style reactors loaded onto vessels, with a hatch near the bow to plug them into local electrical grids. The reactors will generate a combined 70 megawatts of electricity, or enough to power about 70,000 typical American homes. Rosatom plans to serially produce such floating nuclear plants, and is exploring various business plans, including retaining ownership of the reactors while selling the electricity they generate.

The bulky, rectangular structure resembles a big-box store, only with a nuclear emblem of an atom emblazoned on its side. Inside, the floating reactor is a warren of tight corridors, steep staircases, pipes, wires and warning signs in Cyrillic letters.

Officials plan to tow the vessel to coastal cities in need of power, either for short-term boosts or longer-term additions to electricity supply. It can carry sufficient enriched uranium to power the two reactors for 12 years, before having to be towed, with its spent fuel, back to Russia, where the radioactive waste will be processed.

A rotating crew of about 300 Russians, including private security guards, will operate the plant. Rosatom is considering a work schedule where they will remain on board for four months at a time before taking a four-month break. The Akademik Lomonosov will start out serving Pevek, a remote port in Siberia about 500 miles from Alaska, next year.

While on the vessel, the civilian crew will have access to a host of amenities, making the structure a sort of cross between the set for “The Hunt for Red October” and a cruise ship. Those aboard can swim in a pool decorated with pictures of a tropical beach, play squash or strangely, given the seeming importance of sobriety on such a vessel, have a drink at a bar.

“Such a local source of electrical energy, which can easily be transported to difficult-to-access locations, is economically effective,” Vitaly A. Trutnev, the director of Rosatom’s floating reactor program, said in an interview in the captain’s cabin, a suite decorated with orange upholstered chairs and wood laminate tables.

Using nuclear reactors for marine propulsion, or on floating power plants, is not new. The United States used a barge-based reactor to generate electricity for the Panama Canal Zone from 1968 until 1976, and Westinghouse, the American reactor builder, planned — but never built — two floating plants off the New Jersey coast at around that time.

The idea of floating nuclear power won unexpected support after the 2011 Japanese tsunami. That disaster wrecked havoc on the Fukushima coastal power plant by flooding backup diesel generators intended to cool the plant in an emergency shutdown.

A floating reactor, supporters say, would survive tsunami waves at sea. And if an emergency shutdown were needed, it would retain access to cooling, something that is easier to do if it is already in the water, rather than relying on pumps. Rosatom, in a statement, insisted its plant was “invulnerable to tsunamis.”

Professor Buongiorno of M.I.T. has himself proposed floating either small or full-scale nuclear plants on platforms similar to those used in the oil and gas industry. That, he said, would improve the project’s economics and safety as the nuclear industry seeks to compete with cheap electricity from wind, solar and natural gas.

Placing nuclear reactors on vessels could also help reduce the costs of construction. Cost overruns, as well as political opposition, have all but halted nuclear plant construction in the United States. Assembly-line efficiencies at shipyards would help reduce costs.

And then there is the potential climate change benefit. Nuclear power stations generate electricity free of planet-warming greenhouse gases and, unlike other clean sources of energy like wind turbines and solar farms, run around the clock.

Rosatom has so far not disclosed the cost of building the barge, or which countries are interested in buying electricity. The company estimates each floating plant will take four years to build, compared with a decade or so for many nuclear plants. The Sudan Tribune has cited that country’s minister of water resources and electricity as saying the government in Khartoum has a deal to become the first foreign customer. A Sudanese government spokesman, Mujahid Mohammed Satti, declined to comment on the report.

Others are also exploring the technology. China wants to build 20 floating nuclear plants, the first of which will start within two years. A French company has designed a reactor called Flexblue that would not float but rather be submerged on the ocean floor.

But some environmental groups — even those open to a role for nuclear power as a substitute for traditional power plants — are skeptical.

For one, they are not persuaded by Rosatom’s assurances of safety. Critics worry that during a tsunami, the 21,000-ton steel structure might not ride out the wave. In a worst-case scenario, they say, it would instead be torn from its moorings and sent barreling inland, plowing through buildings until it landed, steaming and dented and with two active reactors on board, well away from its source of coolant.

In such a case, Rosatom says, a backup power source and coolant on board would prevent the reactors from melting down, at least for the first 24 hours. “During this time we would consider what to do,” said Dmitri Alekseyenko, the deputy director for Rosatom’s floating reactor program. Regulators in the United States, however, require on-land reactors to operate for 72 hours in an emergency shutdown without external water supplies.

And the fact that the technology is well tested in Russian ships gives critics little solace, given a long history of spills and accidents involving nuclear-powered submarines and icebreakers operated by the Soviet and Russian navies.

In the 1960s and 1970s, the Soviet Union dumped reactors in the Kara Sea, in the Arctic Ocean north of Kola Bay. Russian nuclear submarines sank in 1989 and 2000, while one Russian nuclear icebreaker caught fire in 2011 and the reactor on another leaked radiation that year, according to Bellona, a Norwegian environmental group.

“The question is, would clients of Russia be comfortable with something like this being parked right at a pier in a major city?” Matthew McKinzie, director of the nuclear program at the Natural Resources Defense Council in Washington, said in a telephone interview.

A Greenpeace sailboat tailed the Akademik Lomonosov on its maiden voyage from a shipyard in St. Petersburg to Murmansk, where it will be fueled, flying a banner in English saying: “Floating Nuclear Reactor? Srsly?”

“Like all designs,” Mr. Buongiorno acknowledged, “nothing is perfect.”