Super-Critical Water-cooled Reactors

Supercritical water cooled nuclear reactors are one of the generation four reactor options.

In June 2014, China announced their plan to produce a 1000MWe demonstration SWCR known as SCR-1000, with commissioning scheduled for 2022-2025. China is currently collaborating with Euratom on fuel qualification tests for the SWCR.

BTW – It is not that China is great for making new nuclear reactor technology. China is at a stage of development where they need to rapidly increase the amount of energy per person and they have the money to do it. If China does not go for more nuclear power they would continue to have more coal power and coal power produces a lot of pollution.

Other countries are research SCWR

SCWR System Arrangement signed by Canada, Euratom and Japan (2006) and Russia (2011)

Joint Projects (Canada, Euratom and Japan):
• Thermal-Hydraulics and Safety (PA signed in 2009)
• Materials and Chemistry (PA signed in 2010)
• Fuel Qualification Test (provisional)
• System Integration and Assessment (provisional)

General SCWR facts

* Evolutionary development from current water cooled reactors
• Cooled with light water and moderated with light or heavy water
• System pressure over 22.1 MPa (supercritical)
• Focus on thermal neutron spectrum with option on fast spectrum
• Once through steam cycle
• Plant net efficiency will be over 44%
• Minimum capital costs at given power (improved economics)
• Improved safety, proliferation resistance and sustainability

Some of the Challenges

Coolant enthalpy rise in the core up to 10x higher
* Intermediate coolant mixing in the core?
• Higher coolant core outlet temperatures over 500°C
• Hotter peak cladding temperatures over 600°C
* Stainless steel instead of Zircalloy claddings?
• Prediction of cladding temperatures

*A fast SCWR could be a breeder reactor, like the proposed Clean And Environmentally Safe Advanced Reactor, and could burn the long-lived actinide isotopes.

* A heavy-water SCWR could breed fuel from thorium (4x more abundant than uranium), with increased proliferation resistance over plutonium breeders.