Comparison of hydropower options for developing countries with regard to the environmental, social and economic aspects

With world electricity demand increasing, exploitation of the considerable potential for hydropower generation in many developing countries is an attractive prospect. However, with increased awareness of the potential adverse effects of hydropower and the underlying need for cost-effectiveness, decisions on the scale of new developments are more difficult to make. This paper compares large, small and pico hydropower generation, focusing on the relative adverse environmental and social effects of each, and their economic performance. A hypothetical scenario was formulated featuring three routes to hydro powered rural electrification in developing countries. Costs and population densities were based on data for Pakistan and Peru. Cost-benefit analysis (CBA) techniques were employed to compare the costs and benefits of three hydropower development options providing the same level of service to rural consumers. The results show that investment is recouped 25% more quickly where a number of very small hydro schemes are used instead of one large scheme, but the level of investment required for the single scheme is far greater. Based upon these results, the applicability of hydro projects utilising schemes of different sizes is discussed.