Modern combined-cycle plants produce electricity from two generators: a combustion turbine generator (usually fired by natural gas) and a steam turbine generator, the steam for which is generated from the hot exhaust gas of the combustion turbine. This technology is an efficient way for developing countries with abundant supplies of natural gas to promote the development of gas as a clean fuel, while addressing the need for power sector expansion in the 1990″s. However, use of the technology in developing countries has been constrained by concerns regarding its complexity and the need for advanced high-temperature materials. This paper examines combined cycle power plants installed by A.I.D. in Pakistan and Egypt. Results show that, compared to coal-fired steam plants, the combined-cycle technology has a number of advantages, including: lower capital costs per megawatt, shorter construction schedules, similar availability, higher efficiency, and reduced environmental impact. The report cautions that operations in a power shortage situation induce stresses that may affect long-term reliability or equipment life. Recommendations are offered for electric utilities in developing countries and international donors.
