It is likely that nuclear power within particular sectors will decline over the next 20 years. However, increasing competition will encourage utilities to seek plant life extensions, tending to slow this decline and contribute to reducing carbon dioxide emissions. It is probable that with appropriate investment and refurbishment, the lives of some plants may extend up to 60 years and beyond.

Many present-day reactors are now approaching the end of their design life. There are considerable efforts to extend the operational life of such plants by various means such as backfitting of systems, changes in operational practices, etc. For many countries, the economics of extending the life of existing plants, compared with the capital costs of building new plant, is very favourable. However, the Chernobyl accident in particular has shown that reactor safety is an international concern and economic benefits have to be considered against global acceptability. Decisions on the extension of life depend on a range of technical issues, principally materials performance, chemistry and availability of sophisticated inspection techniques. These and other more general issues (Table 2.9) are reviewed in this section.

Table 2.9. Extension of lifetime issues

Technical feasibility — effect of the processes of ageing?

Plant safety for intended period of operation — ageing of critical safety components? Regulatory framework — establishment of procedures for licence extension?

Social acceptability in national climate — changes during plant lifetime and public perception? Economic considerations — are the economics favourable?