April 16, 2014
Nuclear Plants Could Withstand Tsunamis If Built For Life On The Sea
Brett Smith for redOrbit.com - Your Universe Online
Modern-day nuclear power plants face two major issues: threats from natural disasters such as earthquakes and tsunamis, and finding available real estate near a body of water that could be used for cooling.
A concept being presented at the Small Modular Reactors Symposium this week in Washington, DC could solve both of those problems. According to experts from MIT, the University of Wisconsin, and nuclear plant construction company Chicago Bridge and Iron, a floating nuclear power plant located out in the open ocean could mitigate threats from natural disasters, as well as real estate concerns.
The engineers said the floating power plant would resemble offshore oil drilling platforms and could be immediately cooled by the adjacent seawater in the event of a disaster, which would avert any melting of fuel rods or release of radioactive materials.
According to MIT professor Jacopo Buongiorno, a floating nuclear power plant would be stationed several miles out to sea, secured in around 300 feet of water, would be unsusceptible to the motions of a tsunami and earthquakes would have no direct impact at all. At the same time, overheating and likely meltdown, which happened at Fukushima, would be practically impossible at sea.
"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,” he said. “The reactor containment itself is essentially underwater."
Buongiorno added that building a floating plant would eliminate the complications associated with finding an appropriate site for a land-based nuclear plant.
"The ocean is inexpensive real estate," he noted.
The team said floating nuclear plants might be built in a shipyard, then towed to their locations five to seven miles out to sea, where they would be secured on the seafloor and connected to land by a transmission line. In the event a plant was to become obsolete, it could simply be “decommissioned” and towed away, leaving the surrounding area completely intact.
The engineers said they concept would also cut construction issues and costs through the use of shipyard construction, which allows for better standardization. Additionally, an all-steel design would eliminate the use of concrete, a material that often causes construction delays and cost overruns.
Buongiorno said the design could be built to many different scales, from 50-megawatt plants to the large 1,000-megawatt plants currently in use.
"It's a flexible concept," he said.
The joint team said the operation of these plants would be very similar to the way conventional plants are operated.
"Project work has confirmed the feasibility of achieving this goal, including satisfaction of the extra concern of protection against underwater attack," said Neil Todreas, an MIT professor of nuclear science and engineering and mechanical engineering.
Buongiorno said waters off the coast of Asia, which have both high tsunami risks and a rapidly growing need for new power, might be an ideal location for this new breed of power plant.
"It would make a lot of sense for Japan," he said.