The project will see the “D” Plant at the natural gas facility converted from simple cycle to combined cycle. Combined cycle facilities are 10-15 per cent more efficient than simple cycle gas turbines.
Simple cycle gas turbines generate electricity by turning the turbine using hot gas produced during the combustion process. This type of electricity generation is best for meeting peak loads, such as hotter periods in the summer or colder periods in the winter.
The exhaust air from a combustion turbine is typically very hot 450-600°C and contains useful energy. Large-scale systems will often add a cycle that converts the heat of the combustion turbine exhaust to create steam, which can be used in a secondary steam turbine generator.
The station was officially commissioned in 1959, and has a net capacity of 430 megawatts MW. After the expansion, an additional 205 MW will be added.
Site construction recently began today and is expected to be complete by July 2015. The new plant will be commissioned in September 2015.