Dominance by geothermal energy on the national electricity mix has dipped amid a rise in supplies from the country’s dams, which are more preferred as the cheapest source of power.
An analysis of data shows that geothermal accounted for 43.7 percent or 3,147.5 million kilowatt hours (kWh) between January and July this year in the national grid, marking a nine percent drop from the 3,492.87 million kWh produced in the same period last year.
The drop in the dominance of geothermal came in a period when the share of hydroelectricity on the national grid hit a three-year high of 30.5 percent or 2,202.03 million kWh between January and July.
KenGen, the main supplier of geothermal power, attributed this drop to the merit order rule, which gives priority to the cheapest power source.
The rule also prioritises electricity from intermittent sources, notably wind and solar. “Lower dispatch is likely attributed to higher dispatch from wind and solar sources, which have priority in merit order,” KenGen said yesterday in response to queries from this publication.
However, data shows that the share of wind power dipped to 13.3 percent or 960.47 million kWh between January and July, from 17.3 percent or 1,251.55 million kWh in the same period last year. The share of solar power supplied to the grid fell to 3.67 percent (263.97 million kWh) in the seven months to July from 3.9 percent or 288.38 million kWh in the same period last year.
The merit order says the cheapest source be given priority in order to ensure that consumers get the most affordable power. It also gives priority to intermittent power sources.
The unit price of locally generated hydropower is Sh3.83, making it the cheapest followed by a unit of geothermal power at Sh10.28 while a unit of imported hydroelectricity at Sh10.69 a unit as of February this year.
Increased supply from the country’s hydro-power plants has helped cool the cost of electricity, offering relief to consumers and helping lower inflation— the measure of the cost of living.
Electricity prices dipped 22.3 percent in the nine months to September with domestic consumers (31 to 100 units a month paying Sh1,429 for 50 units, down from Sh1,841 paid for the same units in January this year.
The drop in power prices was largely driven by the strengthening of the shilling against the dollar and a drop in fuel costs given the significant cut in supply from thermal plants.
Geothermal has in recent years been the mainstay of the national grid, helping steady supply, especially at times when hydro-power generation faltered.
For example, between January and July last year, the share of hydropower in the national grid dipped to 19.2 percent due to the biting drought that hit the country.
But this drop was compensated for by the increase in supply from the geothermal sources, whose share hit 48.3 percent or 3,492.87 million kWh.
Heavy rains in April and May this year have since boosted hydropower generation, with production hitting a monthly high of 362.38 kWh in April. The last time it was higher was in May 2021 when some 369.02 kWh were generated.
