Hydroelectric generators: repair or refurbishment?

Whilst many emerging countries are only now beginning to exploit their hydroelectric potential, most industrialized nations had practically completed this development by the mid 1980s so the average age of a European hydroelectric power station is over 30 years. In view of this, the number of refurbishment programmes planned should be increasing rapidly; however, this is not the case. In most instances, the equipment is repaired on a breakdown basis at the lowest apparent cost, such that the opportunity for enhancing the performance of the plant is lost. This paper describes the major technical and economic advantages that can be gained from carrying out a planned refurbishment programme on the equipment and looks at enhancing performance in terms of higher output, improved efficiency, faster response or better reliability. The role played by a manufacturer of new equipment (OEM) is also discussed. The experience, design expertise, and facilities of an OEM not only play a part in assessing the condition of the original plant and determining the necessary scope of work, but also ensure that the full potential for any possible enhancement of performance is realized.