ABSTRACT
Hydrological drought which is considered in this paper is when the water reserves available in the dam/reservoir fall below the statistical average. Hydrological drought tends to show up more slowly because it involves stored water that is used but not replenished. The Volta River Authority (VRA) was established under the Volta River Development Act 1961 (Act 46) with the objective to develop the hydroelectric potential of the Volta River for supply of electric energy for industrial, commercial and domestic use in Ghana and to some neighboring countries. The principal functions of VRA were to generate electric power,
initially, by the construction of a dam and hydroelectric generating station at Akosombo, and to construct and operate a transmission system to carry the power to serve industrial, commercial and domestic needs of the country. VRA’s generation activities cover the operation of two hydroelectric plants one in Akosombo (912 MW) and the other at Kpong (160 MW), also on Volta River, downstream from Akosombo. In addition VRA runs a 30 MW diesel generating station at Tema, which was commissioned in 1992. In 1995, the VRA started constructing a new 330 MW Combined Cycle Thermal generating Plant, comprising two 110 MW Combustion Turbines and one 110MW Steam Turbine Generator and associated Heat Recovery Steam Generator (HRSG) at Abaodze, near Takoradi. The Thermal Project at Aboadze is bringing on board about 660 MW of power. The Asogli Thermal Unit (a private power producer) power plant brings about 12% power. In all electricity from hydro is about 60% against thermal of 40% (PURC, 2011). VRA has been exchanging electrical power with its Ivorian counterparts Energie Electrique de la Cote d’Ivoire (EECI) and Compagnie Ivorienne d’Electricite (CIE) since February 1984. Currently however, VRA is a net importer of electricity from CIE.
