The apparent fundamental movements in the world wide energy market risen by (i) the dramatic increase in world energy demand, (ii) the perceived danger of an ongoing world climate change and (iii) the predicted price and resource trends in fossil resources have risen discussions on the possibilities to significantly further accelerate the development of pure fusion power stations undecontrast at the same time strong fusion specific challenges are being recognized in the light of some issues with the ITER project in terms of schedule, technologies and cost. Therefore, it seems to be appropriate to reappraise the role of DEMO and fusion energy in the overall context and consider readjusting or redefining the medium-term mission in nuclear fusion and its relation to nuclear fission.

Firstly, the current paper assesses synergies with nuclear fission Gen4 reactors. It is ascertained that the development of efficiently helium cooled high temperature components and reactor systems allows for strong collaboration between fission and fusion. Furthermore, it could be concluded that an integrated nuclear strategy for the 21st century should be developed including all important aspects of the possible interplay between fusion and fission. It is briefly discussed whether hybrid fusion-fission systems could be a central point of such an integrated strategy in the world wide context.

The second emphasis of the current paper is on the description of the current progress made in Karlsruhe in the fields of design and testing of helium cooled components for fusion power stations and test facilities. Efficient helium cooling methods for divertor and blanket structures were found by applying the state of the art jet impingement and rib turbulator heat transfer enhancement techniques. The low pressure and the high pressure TBM section of the HELOKA facilities are under assembly. HELOKA is the main experimental tool for out of pile testing and qualification of in-vessel components at Forschungszentrum Karlsruhe.