Recent Technology for Reusing Aged Thermal Power Generating Units

For the continuous operation in another 20 or more years from aged thermal power generating units that have already been operated for 30 years, Fuji Electric has replaced a two-cylinder reheat type turbine with sophisticated single-cylinder reheat type turbine, were reused the existing foundation and nearly all the auxiliary machinery as counter-measures of life prolongation of the plant. By replacing a high-performance single-cylinder reheat type turbine in the limited space of an existing power plant, renewing the insulation of power generating equipment, renewing the high voltage power console and control monitoring equipment, utilizing a digital-electrical governor instead of a mechanicalhydraulic governor, and by adopting an automatic turbine start-up system (ATS) and CRT operation, operability, reliability and maintainability have been improved dramatically. Because this renewal technology can be applied at low cost to aged thermal power generating units, which are comprised approximately 70 % of the total number of thermal power generating units supplied, this technology is expected to be in high demand as a way to provide new solutions to meet customer needs. This paper introduces power generating unit renewal technology, which integrates sophisticated technology with mostly reused equipment from an aged thermal power generating unit to solve the issues concerned with that aged unit, and also presents an example application of the renewal technology. Fig. 1 shows the full appearance of a reused power generating unit.