For the first time in two decades, UK Nuclear Power Engineers and Scientists are optimistic about their role. Perhaps this is a result of the UK government´s concerns about climate change and security of energy supply - but it has clearly decided the nuclear option must be developed. As part of this strategy, the issue of waste immobilization and disposal is being addressed - or at least openly discussed. What will result from all this is not yet clear but some degree of new nuclear build is highly likely.

In this presentation, we will review the generic operation of a power reactor and discuss the designs of reactor that have been built in the UK and a little of the theory behind reactor operation. This will include Sizewell B, our only pressurized water reactor (PWR), which took so long to complete. From this we can consider the options for immediate new build, for example the AP1000 designed by Westinghouse with its advanced passive features or the EPR being built by AREVA. Significantly, an EPR reactor is already being constructed in Finland whereas an AP1000 is yet to be built although it is undergoing pre- licensing in the US. Other types of reactor such as AECL´s CANDU and boiling water designs will also be discussed. Beyond these existing designs are the so- called GenIV (generation 4) options many of which are based on a high- temperature gas-cooled system or on fast reactor systems. There is considerable global co-operative effort in the development of Gen IV but implementation is many decades away. Finally, we will confront the issue of waste. This is crucial because, without a decision on the long-term storage or disposal, new build will never be accepted by the public.