Four projects achieved connection and synchronisation to the Ugandan national grid in 2018, bringing the total of operational GET FiT projects up to ten (10). Unfortunately, some of these projects continue to experience challenges of inadequate and unreliable power evacuation due to technical issues on the grid, which has already led to substantial deemed energy claims from these projects to GoU. Remaining issues need to be rectified in order to reduce such claims and increase power supply.
Figure 13 shows the planned, actual and deemed energy outputs of the GET FiT portfolio projects in 2018 (left axis). It also shows the percentage of deemed energy relative to total potential generation (right axis). As seen in the figure, four projects experience deemed energy levels at more than 10 percent of potential generation, with two projects Nkusi and Siti 1, at more than 25 percent.
Figure 13 - Planned, Annual and Deemed Energy Generation from GET FiT Projects in 2018
*Nkusi, Nyamwamba and Lubilia commissioned during the year and their planned generation is shown for operational months only. Waki commissioned in late 2018 and is not included.
As seen in Figure 13, there is a wide variation in the reliability of power evacuation among commissioned projects. Concerted efforts are needed to strengthen the national grid in order to maximise the benefits of GET FiT distributed generation. The evacuation challenges and interventions experienced by selected projects commissioned in 2018 are highlighted below.
Nkusi SHP experienced the biggest challenges of evacuation during 2018. Following the project’s commissioning in June 2018, the project was initially only able to evacuate 45 % of its capacity. This was mainly due to constraints in the existing grid’s protection scheme and an inadequate network configuration that was suited to power distribution rather than power evacuation.
Additional interventions by various GoU agencies and the developer have since enabled the full evacuation of the project. The full evacuation was facilitated by joint efforts from the developer, UEDCL and Umeme, with oversight from ERA. The key interventions included the reconnection of a 1.5 km line stretch along the Kyenjojo – Kagadi 33 kV line that had been disconnected due to unresolved wayleave issues. The developer covered the wayleaves compensation and the line was reinstated by UEDCL. The rest of the interventions involved the reconfiguration of the grid’s protection scheme for power evacuation through installation of new protection devices and replacement of broken or weak poles, among others.
However, a new challenge arose when the distribution network operator in the project area, UEDCL, reported a significant increase in energy losses resulting from the evacuation of Nkusi. The losses were aggravated by the very long 33 kV lines through which the project is evacuated to the nearest UETCL substation in Fort Portal. Additionally, there is limited electrical load in the project area, hence the need to wheel energy through the long medium voltage lines. The high losses resulted in a temporary cap on the project’s energy generation by UEDCL. The developer is implementing measures to reduce technical losses, including the construction of new distribution lines to create alternative routes of evacuation for increased loading and network reliability.
The Government is also planning to implement measures to optimise the evacuation of Nkusi and other pipeline projects in mid-western Uganda. The key intervention involves expediting the construction of the Muzizi B high voltage substation close to the project area to enable the projects to be evacuated through the recently commissioned Nkenda – Fort Portal – Hoima UETCL high voltage transmission line. Designs for the planned 40 MVA substation are ongoing with coordination between UETCL, REA and the Sector Planning and Coordination Committee (SPCC).
Unlike many other projects, the evacuation line for Waki was built and in place long before the project was commissioned. However, the project experienced several bottlenecks in achieving full evacuation during grid synchronization tests. The challenges were mainly related to the existing line’s fault protection and general maintenance. As a result, the line was initially only able to evacuate 20% of its capacity before tripping during tests in November 2018.
The network operator, UEDCL, implemented several interventions that included general line maintenance (vegetation clearance, pole replacements) and reconfiguration of the protection scheme, i.e. installation of jumpers, drop out fuses and auto reclosers at strategic locations along the evacuation line. The timely interventions by UEDCL and GoU enabled the project to achieve close to 80% evacuation by the time it achieved COD on 3rd December 2018. However, numerous grid failures persist and options are being explored to stabilize the network. The ultimate solution is considered to be the construction of a double circuit 33kV line through Biiso-Kigorobya to the new UETCL 132/33kV transmission substation at Bulemwa near Hoima. The developer has commissioned a study on this implementation.