The outcome from the optioneering exercises and feasibility assessments was that technologies with lower TRLs offer the greatest overall potential benefit, necessitating greater investment in any R&D. For example, utilising fusion neutrons for nuclear waste transmutation would offer commercial viability alongside substantial societal benefits for future generations, but would require a multi-billion pound R&D investment. DEC has substantial technical challenges to overcome to make it possible to practically implement, for example, the large footprint and increased risk of environmental tritium release. However, if DEC was implemented, it could increase the net electricity exported and improve STEP efficiency, hence allowing a return on investment within a reactor lifetime.
Isotope production and materials irradiation are relatively inexpensive to implement and offer low relative technical complexities. Isotope production offers a secure UK supply of medical isotopes and offers a reduced environmental impact compared to the current isotope production methods. Materials irradiation (irradiation programmes, neutron activation analysis, and neutron transmutation doping) has the potential to add value as a reliable and flexible additional income source for relatively low cost.
For each of these technologies, suitable design configurations were determined to enable each application to improve the tritium self-sufficiency. For technologies where tritium self-sufficiency was not possible, costings and practicalities of externally generated tritium was incorporated.