Judging by the comments written, many electricity consumers are still puzzled by the power rationing that followed the shutdown of the Isimba hydroelectric power station for several days after the water leaked into its power plant.
Many are wondering why Uganda, whose installed power generation capacity is 1,346.6 MW, with peak demand of 804 MW (as of June), will boot when Isimba is off.
This reunion seeks to show that there is a difference between installed capacity and actual generation.
Given the permit for the release of 1,000 cubic meters of water per second, the 380 MW Nalubaale-Kiira hydropower system will turn an average of 150 MW in 2022, according to the Report on the revision of tariffs for the second quarter of 2022.
The 250 MW Bujagali Dam will use the same volume of water, generating an average of 163.8 MW.
Bujagali can generate more because it has a higher head from which water falls to spin the turbines.
The report states that Isimba Hydroelectric Power Plant will generate an average of 110 MW in 2022, while Acwa 1 and 2, which have a total installed capacity of 83 MW, will ship only 10 MW to the grid using an average voltage line in the interim due to the lack of high voltage transmission lines from stations to bulk electrical substations.
Due to concerns about the environmental impact of fossil fuels used by heavy fuel plants (global warming), as well as to curb the cost of electricity production in Uganda, only 7 MW is received from the 42 MW Electromaxx heavy fuel oil plant.
From the 32 MW Kakira Sugar plant, UETCL will take an average of 18.3 MW, while only 1.1 MW out of Kinyara's 7.5 MW will be fed to the grid.
Elgon Siti 2 has an installed capacity of 16.5 MW, but since there is no transmission infrastructure, at least 9.1 MW of installed generation capacity is on the grid.
Due to the evaporation of water from energy dams and rivers, as well as precipitation, hydropower can rise or fall accordingly. A block or two of the plant can be shut down for weeks to provide scheduled annual maintenance.
It would be an engineering feat for power plants to produce 100 percent of the installed capacity day in and day out.
Of course, this affects retail rates in the event that factory developers pay for installed capacity.
To address the issue of estimated electricity costs, the government subsidizes connecting consumers to the grid to increase electricity consumption and offset estimated energy costs.
In addition, according to the document of the Ministry of Energy before the House Committee on Ecology and Natural Resources, in the future the construction of hydroelectric power plants will move in tandem with the stringing of the transmission.
Another document says that the energy provision has since been considered.
While some people speculate that Uganda is exploring solar energy to prevent load from being dumped in the future, they may confer solar energy home systems with solar power plants, as Uganda already has five solar power plants with a total installed generation capacity of 50 MW.
Those who are familiar with solar generation know that it is affected by cloud cover. And it takes large batteries and hours in a row to store energy.
The conclusion from the short stop of the Isimba Dam is that Uganda must actually build more renewable energy generation stations using government resources.
The sooner the construction of the Ayago hydroelectric station (Power China makes a feasibility study), Oriang (China Water will take up a feasibility study) and kiba hydroelectric power stations, the better, since experience shows that more than six years pass from the beginning of construction to the date of commercial operations.
Going back to where this letter began, perhaps electricity consumers should draw parallels between power plants and vehicles.
Even vehicles whose speedometers point to, say, 260 or 220 kilometers per hour rarely move at these speeds because there are other variables: used or mint spark plugs, faulty mass airflow sensors, a clogged oil filter, or dust air purifiers that will affect vehicle performance.
In the case of generating stations, this may be hydrology, water resources management solutions (hydropower projects), cloud cover in the case of solar generation, or environmental problems regarding thermal Power plants.
Nelson Vesonga works for Umeme Ltd