WAIRAKEI – STILL GOING AFTER ALL THESE YEARS

Abstract

The development and evolution of the Wairakei steam winning, separators, multistage flash and pipelines has been well documented. The changes in the station’s generating assets have been just as significant, but are relatively unheralded. From an experimental plant in the 1950s with an expected life of twenty years, Wairakei has evolved into a generation facility still reliably operating sixty years later. The nett result is a plant that has set the standard for longevity and load factor. The machines still in service have each done over 400,000 running hours. Many of the components are still original, a tribute to the conservative design. This paper documents some of the issues that have occurred on the station plant and the modifications made to overcome them.