Kenya's Growing Reliance On Wind, Solar is Straining its Power Grid

Listed utility company, Kenya Power, is warning that the rapid growth of wind and solar generation is imposing additional costs and technical pressures on the national electricity grid, forcing it to rely more heavily on other generators to keep electricity supply stable.

• Kenya Power said variable renewable energy, principally wind and solar, now accounts for more than 20% of the grid's firm-capacity measure, above a 15% level it described as a global benchmark. 
• During the daytime peak, when electricity demand is about 1,900 megawatts, variable renewables account for 34% of the energy mix, rising to 36% when demand falls to about 1,200 MW.
• Kenya Power is calling for greater investment in geothermal and hydropower alongside any further expansion of wind and solar, and battery storage for managing fluctuations.

The output of solar and wind energy rises or falls with changes in sunlight and wind conditions. When production drops suddenly, Kenya Power must bring other generating units into operation to replace the lost electricity and maintain the frequency and voltage needed to keep the grid functioning. Those costs can ultimately feed into the price of electricity, particularly where the utility is contractually obligated to pay generators under power-purchase arrangements.

“Our current system under the take or pay model of power purchase 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 MD, Joseph Siror.  

Kenya Power also said the country's variable-renewable share is already the highest in the Eastern Africa Power Pool. It puts Egypt's comparable share at 10.4%, Ethiopia's at 5.3%, Uganda's at 4%, and Tanzania's at 1.2%.

About 78.8% of electricity generation in Kenya comes from renewables, according to the figures from the Energy and Petroleum Regulatory Authority (EPRA). Geothermal accounts for 40.1%, hydropower 22.4% and wind 13%. The remainder of the renewable share is largely solar.

Stabilising the Grid as Demand Grows

Kenya Power is calling for greater investment in geothermal and hydropower alongside any further expansion of wind and solar. It also points to battery storage as a potential tool for managing fluctuations, although storage would add another layer of investment to a power system already facing pressure to contain generation costs.