Energy saving in large steam turbines

Japan depends on imported fuels for its fossil-fuel power plants which are being built for increasingly larger capacities. Improved steam turbine efficiency can contribute to saving fuel in these plants. Therefore, studies were performed to determine where losses occurred in steam turbines at two existing power plants. Components of these turbines were then modified, redesigned and reconstructed to minimize these losses, and the reconstructed turbines were performance tested to confirm the efficacy of the changes. At the Sendai Power Plant, a turbine efficiency improvement of 4.15% was achieved which improved the plant efficiency by 1.72%. At the Niggata Power Plant No. 2 turbine efficiency was improved by 3.81% resulting in a plant efficiency improvement of 1.36%. It was concluded that energy conserving technology should be continuously applied to steam turbine systems. (LCL)