BY DR. ALBERT BUTARE
“Humankind inherited a planet with physical capital and aesthetic beauty – seven thousand, five hundred generations of our ancestors have inhabited it over the last one hundred and fifty thousand years.
Unfortunately, we have begun to adopt points of view that are inconsistent with this legacy and the future, including the following beliefs:
I. Leaps in Technology will effectively mitigate against the depletion of resources; ii. Allocating raw materials to their highest and best uses is, in itself, good morality; iii.There is little inherent value to nature, only as products for us to enjoy; IV. Growth in GDP, by itself, maximizes human well being” President Paul Kagame’s, remarks at the UNGA Summit on Climate Change in New York in September, 2009.
The Ministry of Infrastructure, following the wishes of HE President Paul Kagame of having Rwanda entirely dependent on clean and green energy before 2015, is trying everything possible to engage in initiatives that respond to this green growth path agenda.
To this effect, embarking on renewable energies that include development of methane gas extraction and transformation, geothermal exploration initiatives, solar energy, both thermal and photo-voltaics, wind energy, Biomass energy and hydro-energy has been our top priority. Milestones that have been realized through various initiatives shall be spelt out progressively.
The Hydro-power chapter
The Ministry is currently engaged in the construction of close to 25 pico, micro, mini and hydro plants in the country.
The newly constructed plants and those that are still under construction come in addition to the existing ones that have been in operation for several years. The plants are constructed by different companies and are at different stages of implementation.
This will allow Rwanda to increase the overall national electricity generation capacity in the country by about 70MW, and they shall also allow for electrification of rural areas that are far from the grid.
Overall, a total of 333 mini and micro hydro potential sites have been identified through the hydro-power atlas that was developed by the Ministry.
This comes over and above the Rusumo, Rusizi III and Rusizi IV regional hydropower initiatives that all together make up about 500 MW. The power out put from these initiatives is expected within 5 to 7 years progressively.
The explanation on the progress made thus far in this subsector, may refer to some technical nomenclature that is explained here below;
What constitutes a hydro-power plant?
A Hydropower Plant consists mainly of the following elements:
Intake: is the part of a hydropower installation where water is diverted from the river flow towards the power generation facility.
Weir: a weir is a small dam that can be erected to raise the water level and ensure a constant water supply to the intake.
Headrace channel (Power canal): Water is transported in the headrace channel from the intake to the forebay tank or the head of the hydropower plant in order to maximize the head drop towards the turbine.
Forebay: The Forebay serves as a reservoir for water and allows sediments to settle
Penstock: is a pipe that carries water from the forebay under pressure to the turbine.
Spillway: Is meant to carry the overflow or additional water of the channel at the forebay in a controlled way back into the river. The flow into the penstock can be regulated through diverting water into the spillway.
Turbine: that converts the energy of falling water into rotating shaft power. A coupled generator that then transforms this mechanical power into electricity energy.