DEMO, or a demonstration power plant (often stylized as DEMOnstration power plant), refers to a proposed class of nuclear fusion experimental reactors that are intended to demonstrate the net production of electric power from nuclear fusion. Most of the ITER partners have plans for their own DEMO-class reactors. With the possible exception of the EU and Japan, there are no plans for international collaboration as there was with ITER.[1][2]
Plans for DEMO-class reactors are intended to build upon the ITER experimental nuclear fusion reactor.[3][4]
The most well-known and documented DEMO-class reactor design is that of the European Union (EU). The following parameters have been used as a baseline for design studies: the EU DEMO should produce at least 2000 megawatts (2 gigawatts) of fusion power on a continuous basis, and it should produce 25 times as much power as required for scientific breakeven, which does not include the power required to operate the reactor. The EU DEMO design of 2 to 4 gigawatts of thermal output will be on the scale of a modern electric power station.[5] However, the nominal value of the steam turbine is 790 megawatts, which, after overcoming a 5% loss because of the coupling from the turbine to the synchronous generator, results in a nominal value for electrical power output of approximately 750 megawatts.[6]:5
Project | Injected Thermal Input | Gross Thermal Output | Q plasma value |
---|---|---|---|
JET | 24 MW | 16 MW | 0.6 |
ITER | 50 MW | 500 MW | 10 |
EU DEMO | 80 MW | 2000 MW | 25 |
To achieve its goals, if utilizing a conventional tokamak design, a DEMO reactor must have linear dimensions about 15% larger than ITER, and a plasma density about 30% greater than ITER. According to timeline from EUROfusion, operation is planned to begin in 2051.[7]
It is estimated that subsequent commercial fusion reactors could be built for about a quarter of the cost of DEMO.[8][9] However, the ITER experience suggests that development of a multi-billion US dollar tokamak-based technology innovation cycle able to develop fusion power stations that can compete with non-fusion energy technologies is likely to encounter the "valley of death" problem in venture capital, i.e., insufficient investment to go beyond prototypes,[10] as DEMO tokamaks will need to develop new supply chains[11] and are labor intensive.[12]
{{cite book}}
: CS1 maint: multiple names: authors list (link)