Rusatom Overseas, a subsidiary of Russia’s State Atomic Energy Corporation ROSATOM, and CNNC New Energy (China) signed a Memorandum of Intent to cooperate in the development of floating nuclear power plants. The next step in the implementation of the project will be establishment of a joint Chinese-Russian working group. Rusatom is currently building its first floating nuclear plant, the Akademik Lomonosov; the second of the vessel’s two reactors was installed in February.
The Chinese delegation came to St. Petersburg and Moscow on 24-29 July. The delegation visited the Floating NPP Training Center and the Baltic Shipyard and met with the members of the team for the reference floating NPP construction project, and examined the floating power generating unit currently under construction.
The potential use of floating nuclear power plants is significant. The design provides for two options: self-propelled or barge-mounted floating NPPs [e.g., the Lomonosov]. They might be connected to coastal infrastructure or float next to consumer. Floating NPPs can provide a reliable power supply not only to remote settlements, for example, in the Far North and Far East regions, but also to large industrial facilities such as oil platforms.—D. Aliev, CEO of Rusatom Overseas
The Akademik Lomonosov. Rosatom is building its first floating NPP at the Baltiysky Zavod-Shipbuilding shipyard in St Petersburg. The 70 MWe plant has dual 220-tonne steam generating units, each with a 35 MWe (150 MWt) KLT-40S reactor, based on the reactor unit powering nuclear icebreakers.
|RP flow diagram for the KLT-40S. Click to enlarge.
|Safety levels in the Lomonosov. Click to enlarge.
Russia’s OKBM Afrikantov completed the assembly of the two reactors for the Akademik Lomonosov, in 2009. (OKBM has participated in realization of reactor plant (RP) designs for nuclear ships since 1954.)
The keel of the Akademik Lomonosov was laid in April 2007 at Sevmash in Severodvinsk, but the project was subsequently transferred to the Baltiysky Zavod. The 21,500 tonne hull was launched in 2010, although construction work was frozen in mid-2011 amid bankruptcy proceedings against the shipyard.
The company was subsequently acquired by state-owned United Shipbuilding Corporation and Rosenergoatom signed a new contract in December 2012 with Baltiysky Zavod shipyard for the completion of the floating NPP.
The plant is now scheduled for delivery on 9 September 2016 and will be deployed near the port of Pevek on Russia’s Chukotka peninsula on the East Siberian Sea.
New design for floating NPPs. Earlier this year, researchers in the US presented a new design for nuclear plants built on floating platforms, modeled after those used for offshore oil drilling. Such a design, as described at the Small Modular Reactors Symposium by MIT professors Jacopo Buongiorno, Michael Golay, and Neil Todreas, along with others from MIT, the University of Wisconsin, and Chicago Bridge and Iron, could ride out tsunamis. Such floating plants would be designed to be automatically cooled by the surrounding seawater in a worst-case scenario, which would indefinitely prevent any melting of fuel rods, or escape of radioactive material.
Such plants, Buongiorno said, could be built in a shipyard, then towed to their destinations five to seven miles offshore, where they would be moored to the seafloor and connected to land by an underwater electric transmission line. The concept takes advantage of two mature technologies: light-water nuclear reactors and offshore oil and gas drilling platforms. Using established designs minimizes technological risks, says Buongiorno, an associate professor of nuclear science and engineering (NSE) at MIT.
The current concept of a floating nuclear plant on a barge moored at the shore—e.g., the Akademik Lomonosov—is not located far enough offshore to be able to ride out a tsunami, Buongiorno says. For this new design, he says, “the biggest selling point is the enhanced safety.”
A floating platform several miles offshore, moored in about 100 meters of water, would be unaffected by the motions of a tsunami; earthquakes would have no direct effect at all. Meanwhile, the biggest issue that faces most nuclear plants under emergency conditions—overheating and potential meltdown, as happened at Fukushima, Chernobyl, and Three Mile Island—would be virtually impossible at sea, Buongiorno said.
It’s very close to the ocean, which is essentially an infinite heat sink, so it’s possible to do cooling passively, with no intervention. The reactor containment itself is essentially underwater.—Jacopo Buongiorno
At the end of a plant’s lifetime, decommissioning could be accomplished by simply towing it away to a central facility, as is done now for the Navy’s carrier and submarine reactors.
This design could also help to address practical construction issues that have tended to make new nuclear plants uneconomical: Shipyard construction allows for better standardization, and the all-steel design eliminates the use of concrete, which Buongiorno said is often responsible for construction delays and cost overruns.
There are no particular limits to the size of such plants, he said: They could be anywhere from small, 50-megawatt plants to 1,000-megawatt plants matching today’s largest facilities.
Buongiorno sees a market for such plants in Asia, which has a combination of high tsunami risks and a rapidly growing need for new power sources.
This is a “very attractive and promising proposal,” said Toru Obara, a professor at the Research Laboratory for Nuclear Reactors at the Tokyo Institute of Technology who was not involved in this research. “I think this is technically very feasible. Of course, further study is needed to realize the concept, but the authors have the answers to each question and the answers are realistic.”
Jacopo Buongiorno, Michael Golay, Neil Todreas, Angelo Briccetti, Jake Jurewicz, Vincent Kindfuller, Daniel Fadel, Ganesh Srinivasan, Ryan Hannink, Alan Crowle and Michael Corradini (2014) “Offshore Small Modular Reactor (OSMR): An Innovative Plant Design for Societally Acceptable and Economically Attractive Nuclear Energy in a Post-Fukushima, Post-9/11 World,” ASME 2014 Small Modular Reactors Symposium doi: 10.1115/SMR2014-3306