Researching sustainable techniques to improve electricity generation
and transmission from hydropower systems in rural Uganda
Background
This summer 7 University of Warwick Students went out to Western Uganda to build hydroelectric systems in rural
Villages. The project was started in 2009 and is supported by Dr. Colin Oram. Lack of electricity is a major barrier
to economic growth and due to the kerosene lamps used instead of electricity also has negative health benefits.
Electrifying villages also increases education prospects and students can revise at night, especially important as
the sun sets in Uganda at 5pm every day. Non-renewable methods of electricity are not a sustainable or smart
idea. Not only do they pollute the environment, but they also deplete the local natural resources, which could be
used for an income or to build houses. There for sustainable methods of electricity are the only real solution. Uganda is land locked, so tidal is not possible, There are not many sunlight hours and the rainy seasons are regular, so
solar power is not feasible. However as we were working in the mountains there are many streams, which provides
the possibility of hydropower which has been agreed as the most appropriate effort. In the previous years, 3 different sites have been selected for this project and this summer we carried on their work.
Before
After
Increasing power output in Bihondo
Bihondo is the village where we did most of the work, with the overall aim of increasing the power supply. Work was started last year, with the installation of pipes
and initial building of the power house. We built and cast a dam out of concrete
and cast a channel to connect the dam to the sedimentation tank. A sedimentation
tank is required so that the majority of particulates in the water settle in the tank
and do not make it down to the turbine and cause damage. We built up the new
powerhouse, which protects the turbine, and installed pipes to go to the power
house. This system is improving from the old one, as the powerhouse is further
away from the source, meaning that the head and thus power is increased. A concrete and brick channel replaces a plastic pipe which was prone to splitting due to
UV exposure.
Creating a Business plan and testing and installing limiters in Bihondo
A major issue in Bihondo is regulating how much energy each house uses. Before this summer they
regularly went round and made sure that people were only using one lightbulb, however the system
was being occasionally overloaded, which meant power cuts for the whole village. This summer we
surveyed the village and found out how many lightbulbs each house wanted, which would soon be viable due to the increased power. After discussing with the committee, we decided to have an increased
price per lightbulb, which meant we had to limit the amount of power each house could take. We did
this by testing a load limiter, which once a certain current is reached, the temperature will increase and
so will the resistance, so that no current may pass. These are reset by breaking the circuit and allowing
the limiter to cool. We tested these and created boxes to connect to the houses, depending how many
lightbulbs they paid for. In addition we discussed with the committee and the local community about appropriate pricing. Once this was agreed we were able to use the survey to predict how much money
they could make and then we estimated their other costs, worked out their turnover then worked out
an amount they could pay back to the scheme. Although their contribution is not essential, it is important that they pay something to wards the scheme so that they feel an ownership and responsibility
for maintaining it.
Powerhouse and Wiring for Mount Gessi School
Last years team had set a concrete channel for part of the system and 3 years
ago a team had wired some of the classrooms and put up poles. This year we carried on that work by building a power house, installing a vertical turbine and damming the river. In addition we rewired the class rooms, with better quality wire and
light fittings and detangled the steel wire on the poles.
Results and Conclusion
The final day we were in Bihondo there was a large storm with very heavy rain. When we went to check on
the dam and sedimentation tank, we found that the river before the dam had burst its banks. This caused
water to flow around the sedimentation tank, which weakened one of the walls and caused it to collapse. In
some ways this was lucky, as it meant it could be fixed, as some of the members were staying a little longer.
Increased power was returned to the village a few days later. With regards to the business plan, it was well
received and after a few explanations, everyone understood. The limiters were being installed by the local
technician when we left and the business plan was being followed. We will know how successful this part of
the project was when the team returns next year. Mount Gessi School was very successful with all classrooms newly wired and a reliable power system. Overall the project was a success, with many things
achieved and learnt by both the team and the local community.
Laura Sparks, School of Engineering, Project Supervisor: Colin Oram