Nuclear power represents an almost limitless energy resource for power generation and propulsion applications. Using current ‘nuclear fission’ know-how with exploitable elements like uranium for fuel, nuclear power can sustain the world’s current and future energy needs for hundreds of years. Understanding of this technology is going through a step change, however, and the next generation of fission power reactors has the potential to fulfil global energy requirements for at least 1,000 years.
Nuclear-powered submarines can remain submerged for long periods because of self-contained nuclear propulsion systems. Most, including Royal Navy submarines, incorporate a pressurised water reactor (PWR) to raise steam to drive turbines for propulsion and for on-board electricity production. For Britain’s latest nuclear-powered submarines, the Royal Navy is now using the second generation of a larger Rolls Royce PWR2 core that lasts four times longer than predecessors, eliminating the need for removal from service for mid-life refuelling.
Elsewhere in the world, nuclear power is also used for surface ship propulsion, with notable current applications being US aircraft carriers and Russian ice breakers. Nuclear power has been used for some civilian cargo ships, but was found not to be economic and only a few vessels were made during the 1960s. However, present economic realities of much higher fuel prices and global concerns over CO2 emissions have brought about renewed interest in nuclear power for suitable civilian applications.