Two decades of commercial nuclear power. A review of nuclear power station performance in the United Kingdom

In the 20 years since the start of the commercial nuclear power programme in the United Kingdom, the initial activities concerned with the achievement of high availability on plants of a new design have given way to those concerned with the improvement of maintenance methods and modifications to overcome obsolescence. Gas-cooled reactor designs have evolved and construction techniques have been developed to improve reactor output and steam conditions. Modern methods of engineering analysis and in-service inspection are being applied to plants conceived in the early 1950s in order to re-evaluate their adequacy in the light of current practice. One of the outstanding successes of the Magnox programme has been the reliability of the fuel. Fuel development and post-irradiation inspection programmes have given rise to increased endurance and utilization without loss of plant availability. The substantial economic advantage provided by nuclear generation dictates that the plant should be operated at high load factors to the end of its life. Recruitment policies, organization structures and training schemes have been designed to provide adequate numbers of suitably qualified staff and to ensure succession in an ageing staff population. A power station cannot be operated in isolation from the community in which it is situated. The means by which the community is kept informed in both normal and emergency conditions have been developed to match the changing attitudes of the population towards nuclear power. This paper reviews briefly the evolution of gas-cooled reactors in the UK, describes the improvements in fuel performance which have been achieved, discusses factors which will determine the life of plants and identifies significant features of the operation and maintenance of nuclear stations. (author)