In the 1990s, it was converted from a gas turbine power plant to a combined cycle plant. The combined cycle plants include combined cycle plants 1 and 2, combined cycle plants 3 to 5 and combined cycle plants 6 and 7. The Gas Plant Stage I was an open cycle plant with 4 open cycle gas turbines with 131 MW capacity when commissioned in 1991. In 1994, the 4 open cycle gas turbines were converted into two blocks of combined cycle plants with 425 MW of capacity each and renamed CCP 1 and 2. In 2010, Gas Turbine GT22 of CCP 2 was upgraded with new vanes and blades for its stage 1 and 2