TABLE OF CONTENTS M. Cregan and D. Flynn
Fossil fuelled power plants have been supplying electricity for industrial use since the late 1880s. At first, simple d.c. generators were coupled to coal-fired, reciprocating piston steam engines. Electricity was delivered over relatively short distances, and was primarily used for district lighting. The first central generating station was opened by Thomas Edison in September 1882 at Pearl Street, Lower Manhattan, New York City. Lighting alone, however, could not provide an economical market for successful commercial generation, so new applications for electricity needed to be found. The popularity of urban electric tramways, and the adoption of electric traction on subway systems, coincided with the widespread construction of generating equipment in the late 1880s and 1890s.
Initial power plant boiler designs generated steam in a simple water tube boiler, from a coal or coal gas supply. They typically operated at 0.9 MPa (8.6 bar) and 150 C (300 F), and would have been connected to a 30 kW generator. Since then the topography of the typical power plant has evolved into a highly complex system. Today, advanced turbine and boiler designs, utilising new metal alloys, can operate at supercritical conditions of 28.5 MPa (285 bar) and 600 C (1112 F), generating 1300 MW of electricity (Smith, 1998; DTI, 2000).
In a search for reduced operating costs, plant design has moved on from generating units based on the Rankine cycle, which typically achieved thermal efficiencies in the range 30 40 per cent. Now combined cycle gas turbine (CCGT)...
