Finding Potential Sites for Small-Scale Hydro Power in Uganda: a ...

of the worlds primary energy supply. The share of hydropower energy supply inindustrialized countries was not expected to change significantly in the next 25-30 yearsbut was thought to become more prominent in the developing countries, as illustrated inTable 3.4.Table 3.4 Estimates of share of hydro sources in primary energy supply (% of primary energy). Source:WEC, 1994.Year 2005 Year 2020Moderate growth Low growth Moderate growth Low growthIndustrialized countries 6.0 5.8 6.5 6.2Developing countries 6.8 6.2 9.7 8.5World total 6.3 6.0 7.7 7.3Figures for the exploitable small-scale hydropower potential can be no more thanspeculative, however WEC (1994) estimates that 5% of the total hydropower potentialthought to be exploitable is perhaps of the right order of magnitude. This gives a netexploitable potential of 630 TWh of which just less than 10% has been developed.Another way to point out the potential of small-scale hydro is by adapting the twoscenarios: “current policies” and “favorable”. The current policies scenario is based on aprojection of existing trends. Some of the circumstances leading to the “favorable”scenario are national commitments to support the development of renewables,minimization of development constraints, reasonable real interests rates and adequatefinancing for worthy projects in developing countries. Estimates of generation capacityand electrical output by region through 2020 are presented in Table 3.5 (WEC, 1994).Based on the information given in Table 3.5, by year 2020, approximately 40% of the netexploitable potential or small-scale hydropower will be developed.Small projects lack the advantage of scale and their cost per installed kW can therefore bequite high. According to WEC (1994) the investment costs for projects in the range of500 to 10,000 kW can be expected to lie in a range of about USD 1,500 to 4,000 per kW.23