Large aircraft carriers are essentially ocean-going nuclear power plants.
Nuclear power is a technology with great promise. It produces large amounts of low-emission electricity for a relatively low investment of fuel. One of the most serious drawbacks of nuclear power is the possibility of a meltdown: a catastrophic release of radioactive material due to overheating of the reactor core. One proposed solution to this issue is the construction of nuclear power plants on or in the ocean.
Marine Nuclear Power
The idea of building an offshore nuclear power plant is not as novel as it might appear. After all, the first oceangoing nuclear reactor was launched aboard the USS Nautilus in 1955. To date, the U.S. Navy has deployed hundreds of marine nuclear reactors aboard submarines, aircraft carriers and cruisers. The largest nuclear reactors afloat produce about 500 megawatts, enough to power about 150,000 homes. In over a half century of using nuclear powered vessels, the Navy has never had a nuclear accident, which lends some credence to the viability of marine nuclear power.
The main advantages to building offshore nuclear power plants are safety, isolation and security. By being surrounded or immersed in seawater, the plants would have constant access to emergency coolant. In the case of a major disaster, the contaminated area would be less likely to overlap with human habitation than a land-based plant. Since they would only be accessible by boat or, in the case of submerged plants, mini-subs, they would be less vulnerable to terrorist attack. Finally, they could be used to power isolated coastal regions with a minimum of land-based infrastructure.
Disadvantages and Fears
The most obvious disadvantage of an offshore nuclear plant is the possibility of an underwater nuclear disaster. Besides the possibility of actual radioactive material spilling into the sea, the heat generated by a nuclear meltdown could kill or disrupt sea life over a wide area. Even the constant outflow of waste water heated by the nuclear reaction could harm species adapted to colder seas. These fears are hard to quantify or refute, since there is much less data on the effects of nuclear accidents in the ocean than those on land. Offshore reactors may also be more vulnerable to hurricanes and tsunamis, although the danger applies mostly to floating plants rather than submerged reactors.
The most immediate plans for implementing offshore nuclear reactors are being pursued by Russia, who hopes to have a floating nuclear power plant in place and producing electricity within two years. France is actively pursuing plans to build submerged nuclear reactors in the English channel as part of their robust nuclear power policy.