Technology Development

The nuclear power industry has been developing and improving reactor technology for more than five decades. Several generations of reactors are commonly distinguished.

Generation I: Reactors were developed in 1950-60s and very few are still running today. They have been referred to as “early prototypic reactors”.
Generation II: Developed in mid 1960s, “active safety system” was often being used in this generation’s reactors. The safety system involves electrical or mechanical operation on command, which means they are activated by human controllers and cannot operate if electrical power systems are shut down. About 90% of nuclear power plants operating today employ Generation II technology. Many of them have incorporated some passive or inherent safety features requiring no active controls or operational intervention for accidents avoidance in the event of malfunction, and may rely on gravity, natural convection or resistance to high temperatures.
Generation III: Advanced Reactors developed in Mid-1990s, their designs incorporate further passive safety systems which is to increase reactor safety by operating without human intervention or electrical power. European Pressurised Water Reactor (EPR) and the Westinghouse Advanced Plant 1000 (AP1000) pressurised water reactor belong to this group.
Generation IV: Designs of this type of reactors are still on the drawing board and will not be operational before 2020 at the earliest, and probably later. They will tend to have closed fuel cycles and burn the long-lived actinides now forming part of spent fuel, so that fission products are the only high-level waste and the time taken for its radioactivity to fall to a safe level will be far shorter. Many designs will be fast neutron reactors.