The need for research into suitable materials for components that need to withstand the aggressive high temperature and corrosive environments of future generation plants has been mentioned earlier.

Key considerations are economics and how to reduce construction cost without compromising safety. Some particular areas in HTRs where cost savings could be made included the following. The heat recovery in high temperature gas designs incorporates a large tube-in-shell heat exchanger to recover helium heat discharged from the turbine, before it is recycled. The inclusion of an advanced plate type heat exchanger would result in much reduced size and, therefore cost.

Another area is the load imposed on the helium turbine bearings. Such large turbines have not been built or operated. One option might be to increase the speed of the power turbine, thus reducing its weight and size, and therefore possibly allowing the use of gas bearings.

Much work has been done of passive devices for innovative reactors. There needs to be a better understanding of the limits of the safety devices used on present day operating reactors. The issue is how to extend the existing devices to innovative reactor applications or, if necessary, how to develop new ones.