Evolution of Reactor Design

As in most other technological areas, the development of nuclear technologies is an evolving process that involves the continuous pursuit of more intrinsic safety. Major advancements to date cover designs for passive protection that will enable reactor cooling in the event of total power loss. Other potential breakthroughs include the possible replacement of Uranium with alternative natural resources such as Thorium in nuclear fission and Lithium and Deuterium in nuclear fusion. Scientists worldwide are also looking at new energy generation technologies to enhance efficiency or address issues arising from conventional technologies (e.g. reducing the amount of radioactive waste). Often referred to as the fourth generation or subsequent nuclear technologies, these approaches are currently in various stages of development.


High Temperature Gas-cooled Reactor


  1. An emerging reactor design whose "fail safe" feature enables reactors to cool down in safety mode by passive means in case of total power loss.
  2. It normally runs on hot gases at temperatures of above 700°C and so has a higher efficiency in power generation.
  3. Countries involved in their development include China and the United States.



Fast Neutron Reactor


  1. These highly efficient new reactor types use highly-enriched Uranium U235 and Plutonium Pu239. As extra neutrons are generated during the nuclear fission process which can be used to produce new nuclear fuel, the technology measurably enhances Uranium's effectiveness in generating power.
  2. While using the same amount of Uranium, the energy generated by this type of reactor is 60 times that generated by conventional technologies, through converting Uranium 238 which makes up the bulk of natural Uranium into Plutonium Pu239 for nuclear fission.
  3. The technology will also allow the conversion of Thorium which is far more commonly found than Uranium into a usable nuclear fuel.
  4. Their prototypes have already been built and operated. They are now also being considered for future commercial development.
  5. Countries involved in Fast Neutron Reactor development include China, Russia, the United States and various European nations.

Fusion Reactor


  1. A fusion reactor uses two different forms of Hydrogen (i.e. Tritium and Deuterium), to fuse together and generate energy.
  2. Resources abundantly found in nature, they ensure the security of fuel supply.
  3. As the end product of this reaction process is radiation-free Helium, the key advantage of Fusion Reactor is that they generate no high-level radioactive waste. This greatly reduces the likelihood of environmental problems.
  4. Involving almost all major nuclear-using countries, the multinational International Thermonuclear Experimental Reactor project is currently leading the effort to commercialise fusion-powered reactors by 2050.