The European fusion programme is based on the Roadmap to the realisation of fusion energy. The roadmap breaks the overall task into eight missions. EUROfusion funds the Research Units in accordance with their participation to the mission-oriented Work Packages outlined in the Consortium Work Plan. Each Work Package is lead by a team of project leaders from the Research Units.
In general the programme has two aims: Preparing for ITER experiments and developing concepts for the fusion power demonstration plant DEMO.
The objectives of the EUROfusion ITER Physics Programme for ITER lie in the development of plasma regimes of operation for ITER and in investigating solutions to manage the plasma’s heat exhaust. The second issue is connected with concepts for the divertor, which is the area of the reactor wall that experiences the highest heat and particle fluxes. ITER Physics also studies divertor configurations that could reduce this heat loads.
Laying the foundation for a Demonstration Fusion Power Reactor (DEMO) to follow ITER by 2050 is the objective of the EUROfusion Power Plant Physics & Technology Work Programme. The central requirements for DEMO lie in its capability to generate several 100 Megawatt of net electricity to the grid and to operate with a closed fuel-cycle (i.e. to produce and burn tritium in a closed cycle). A number of outstanding technology and physics integration issues must be resolved before a DEMO plant concept selection is made. Each of them has very strong interdependencies. One is the selection of the concept for the breeding blanket. Blankets are the internal components of the reactor wall that absorb the energy from the fusion reaction, ensure the tritium breeding process and shield the components outside the reaction chamber from the fast fusion neutrons. The choice of cooling fluid flowing through the blanket is closely connected to the selection of the Balance of Plant. The latter denotes the sum of all systems that transform the fusion energy into electricity – mainly cooling fluid, turbine and generator. Another matter is the selection of the divertor concept and its layout configuration. The design of the first-wall (i.e. the innermost lining of the reactor wall) and its integration into the blanket is a further issue, since it must take into account that the first-wall might see higher heat loads than assumed in previous studies. Furthermore, there is the selection of the minimum pulse duration of DEMO and of the corresponding mix of plasma heating systems (i.e. heating and current-drive systems). DEMO must be designed in a way that all maintenance work can be carried out remotely via manipulators and therefore reliable and fast maintenance schemes must be selected. The impact of the various system design options on the overall plant reliability and availability are analysed in an integrated approach. The development of DEMO requires many technological advances and innovations in several areas. One example are structural materials that withstand both extreme heat loads and the bombardment with neutrons of unprecedented energy. Another issue is the heat load – not only on the divertor, but also on areas of the reactor wall.