Optimisation of Turbine Plant as Part of an Integrated Retrofit Project

In 2006 Eskom awarded a contract for the retrofitting of the boiler and turbine plant on 6 350MWe units in South Africa. The object of the project is to ensure that the continuous unit rating is increased to 400MWe whilst retaining as much of the existing plant as possible. In addition the plant life will be extended by twenty years. The optimisation process began with the development of various thermodynamic options which would allow a range of power increases. These were then integrated into an economic model which allowed the best option to be identified. In general, a key objective while retrofitting plant is to limit the extent of plant to be changed while still being able to meet the newly defined plant operation conditions, thus allowing for full utilisation of the current assets. This paper details the process followed in the development of the turbine plant retrofit solution. Particular attention is given to the successful Contractor’s Integrated Retrofit Project philosophy, which allows for full optimisation and integration of new components into the plant, while giving assurance of the suitability of the retained equipment.