A number of challenging experiments were carried out in the 80’s and 90’s all over in the world providing very important progress in fusion technologies and physics.
In the 90’s, in the frame of a strong European cooperation project, the JET (Joint European Torus) provided a fusion power gain Q>0.6 (16 MW of nuclear fusion power Pfus obtained by D-T reactions, with 25 MW of input heating power Pin).
The next step is ITER , in construction at Cadarache (France). Its mission is to improve Q to about 10 (Pfus=500 MW from Pin=50 MW), by increasing magnetic field, plasma current and machine dimensions.
Further step is DEMO, Demonstration Fusion Power Plant, a new international project presently under design. Its main mission is the production of electricity from fusion to be injected in the electric commercial network.
The European fusion community identified eight important missions on the path towards fusion electricity EUROfusion European Research Roadmap to the Realisation of Fusion Energy :
- Plasma regime of operation
- Heat-exhaust system
- Neutron resistant materials
- Tritium self-sufficiency
- Implementation of intrinsic safety features of fusion
- Integrated DEMO design and system development
- Competitive cost of electricity
- Alternative to Tokamak configurations (Stellarator).
DTT is a key facility in the framework of mission n. 2 ("Heat-exhaust system"). It is aimed at carrying out alternative solutions to the problem of disposing the heat load. Here following an interesting statement:
“If alternate exhaust strategies were to be only explored in the event of ITER showing that the baseline exhaust strategy cannot be extrapolated to DEMO, the realisation of fusion would be delayed by at least 10 years…. for the alternative approaches the extrapolation from proof-of-principle devices to DEMO based on modelling alone is considered too large. If a promising alternative concept emerges, a divertor optimised for the concept will be implemented in the Italian Divertor Test Tokamak (I-DTT) facility as a joint European collaboration. ”
Tony Donné, William Morris, et al., “European Research Roadmap to the Realisation of Fusion Energy A road map to the realisation of fusion energy”.