Kenya Power Warns Rising Wind, Solar Generation Threatens Grid Stability

Kenya Power has raised concerns about the vulnerability of the country’s power grid due to a surge in generation from variable renewable energy (VRE) sources, particularly solar and wind.

VREs currently account for 34% of the total energy mix during peak daytime demand of 1,900 megawatts (MW), and 36% during periods of low demand of 1,200 MW, according to Kenya Power.

In a statement on Tuesday, the power distributor said the growing share of variable renewable energy exposed the national grid to system vulnerabilities when wind and solar generation suddenly dipped or increased, forcing the grid to rely on other generation sources to cushion the intermittency.

Kenya Power called for a careful balance in integrating VRE generation sources to mitigate their impact on the grid.

The intermittency of wind and solar power can affect the reliability and quality of electricity supply through their impact on grid frequency and voltage, the company said.

Kenya Power said grid stability should be prioritised and the additional costs required to supplement variable sources should be considered when integrating new generation capacity. This would help mitigate power outages and safeguard the quality and cost of electricity for consumers, it said.

“Global benchmarks point to a limit of 15% of the grid’s total firm capacity for VRE. Our current system under the take-or-pay model of power purchases has led to an increase in VREs to over 20%, against a recommended average of 15%. Given the intermittent nature of wind and solar, we have no option but to dispatch and pay for generators, increasing the overall cost of power,” said Kenya Power Managing Director and CEO Joseph Siror.

Kenya Power currently dispatches additional generation plants at extra cost to mitigate the risk of grid instability when VRE output suddenly falls or rises, a common occurrence that ultimately increases costs for final consumers, Siror said.

“For VREs, the recommendation is to have battery storage systems. However, they would still face a challenge in charging the batteries when the wind and solar dip. The true cost of VREs is its own cost and the additional power that we pay for to stabilise the grid,” he said.

“Therefore, investments in geothermal and hydro offer greater grid stability and ensure the grid can recover and remain productive when intermittent sources are unavailable,” Siror added.

Kenya has the highest dependence on VREs in the region, according to Kenya Power. Within the Eastern Africa Power Pool, Egypt’s VRE share stands at 10.4%, Ethiopia’s at 5.3%, Uganda’s at 4% and Tanzania’s at 1.2%.

Kenya’s current baseload generation comprises geothermal, hydro, power imports and thermal generation, which together account for 80% of the grid’s energy mix, the company said.

Kenya Power has called for an increase in baseload generation, which it said is more stable and less susceptible to fluctuations in output.

New baseload sources expected to be introduced to the grid include KenGen’s Olkaria I, with 61 MW; KenGen’s Olkaria VII, with 80 MW; Globeleq Menengai, with 35 MW; Orpower’s Menengai project, with 35 MW; 200 MW of imports from Ethiopia; Paka Silali, developed by the Geothermal Development Company (GDC), with 100 MW; and Nabuyole, with 28 MW.

Plans to raise the level of the Masinga Dam by 1.5 metres are also expected to increase annual electricity generation by 83 gigawatt-hours (GWh), the company said.

Other baseload generation projects in the pipeline include a planned liquefied natural gas (LNG) power plant, initially proposed at 300 MW, the 700 MW High Grand Falls project and the 90 MW Karura Falls project.