MIT researchers propose building nuclear reactors in offshore locations, due to several strategic and practical safety advantages.
Standard nuclear reactors are water-cooled, and water can be cycled within its system solely as a coolant, or can be used to generate steam for a turbine. This is often the reason why nuclear power plants are built near bodies of water. MIT, however, plans to upgrade this simple safety concept by pulling the nuclear power plant itself deep into ocean waters.
Much like an oil rig or other deep-sea floating platform, the nuclear power plant can be setup first on a nearby port, with the completed structure being simply towed to its destination. The main concept for this idea is to prevent any worst case scenario that would usually lead to an eventual core meltdown. The vast source of water on site would provide MIT’s proposed nuclear reactor with a very large coolant reservoir.
But more than having an almost infinite resource of water for its cooling system, MIT also says that offshore nuclear power plants have the advantage of environmental safety. First, a nuclear reactor that is several miles off the coast would be significantly less affected by tsunamis, and wouldn’t be affected by earthquakes at all. Second, in case of an actual core meltdown, since it’s far away from land, it wouldn’t affect residential areas and populated areas as much as it would have. Even then, the nuclear power plant may simply be towed away again to a safer location. Finally, a well established design using already known technologies minimizes operational risks, which is usually the issue that is most commonly addressed when designing new nuclear power plants.
Take note that seawater is not directly used as a coolant in nuclear reactors. Mineral content in seawater poses a considerable risk to safety and maintenance, as it slowly accumulates in the reactor’s containment unit. MIT’s offshore nuclear reactor would most likely use a desalinization system to purify seawater before use, which could simply be powered using the excess heat generated by the nuclear reactor.
MIT has recently presented the concept at the Small Modular Reactors Symposium. While there are no direct plans or startup projects that would utilize the concept in the near future, opinions are generally optimistic about its implementation. Actual feasibility of course is still subject to further study and research however.