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

To determine the electrical power potential of site 19, in vicinity of the village Nyambarein Nyamabare parish, the following steps were made:To calculate the electrical power we first need to calculate cross-sectional area, flow andhead. This is done by using equations 4.3, 4.4 and 4.2.o Area:2(0.3 m ⋅ 0.5 m)/2 = 0.075 mo Flow:230.075 m ⋅ (1m/s ⋅ 0.65) = 0.04875 m /sWhere 0.65 is a correction factor for a small slow clear streamo Net head:ο100 m ⋅ sin 15 = 25.9 m25.9 m – 25% = 19.4 mWhere 25 % equals the loss of power due to penstock friction.By using equation 3.1 we then calculated the hydraulic power.o Hydraulic power:19.4 m ⋅ (0.04875 ⋅1000)l/s ⋅ 9.81 = 9283 WAs stated in section 3.1.2, there is a power loss of 35% in the turbine when the hydraulicpower is converted to mechanical power. There is also a loss of power when convertingto electrical power. As in the example in section 3.1.2, we have calculated with agenerator efficiency of 80 %, which gives the site at Nyambare the potential electricalpower of 4.8kW.o Mechanical power:9283 x 0.65 = 6034 Wo Electrical power:6034 x 0.8 = 4827 W or 4.8kWThe same calculations as above have been applied on the sites 2 and 25 to estimate theirelectrical power potential. Site 2 near the village Nyamatembe in Kacherere parish has anelectrical power output of 1.9 kW and site 25 near the village Rusiza in Busengo parish,48.4 kW. Information about all evaluated sites is attached as Appendix 9.5.55