A report from the Royal Society, the UK’s independent scientific academy, suggests that nuclear plants should be able to switch output between electricity and heat so as to fit in better with increasing proportion of power from intermittent renewables. Its main focus is heat rather than surplus electricity (as with so-called ‘green’ hydrogen), and it outlines a number of cogeneration options for either low or high-temperature heat. For low temperatures (100-200°C), district heating is already well established in other countries using what is otherwise waste heat, and 50 conurbations in UK have potential. For high temperatures (over 400°C, and representing 26% of total industrial heat demand in EU), hydrogen /ammonia production and desalination are both options where the product can be stored, so need not be continuous in the same way as meeting base-load electricity demand. Coal to liquids processes can also use heat in this range. In the UK 14 of its nuclear fleet are Advanced Gas-cooled Reactors (AGR of 480 to 620 MWe each) which operate at over 600°C, as do a few of the advanced small modular reactors under development. An Appendix considers nuclear steelmaking.
