Kenya Power wants the country to slow down on wind and solar, at least in how fast new capacity gets added to the grid. The utility says variable renewable energy, wind and solar combined, now supplies 34 percent of the national energy mix during evening peak demand of 1,900MW and climbs to 36 percent when demand drops to 1,200MW overnight.
That share has pushed VRE capacity past 20 percent of the grid’s firm capacity, well above the 15 percent ceiling the utility says international benchmarks recommend.
The warning, issued August 11, does not call for halting renewable energy development. It calls for pacing it against the grid’s ability to absorb power sources that can swing from full output to near zero within minutes.
Why intermittency costs money
Wind and solar generation rises and falls with weather, not demand. When output from these sources drops suddenly, the grid operator has to bring in other generation fast enough to prevent frequency and voltage instability, the kind of swings that can trigger outages if left unmanaged. Kenya Power says it currently has no option but to dispatch and pay standby generators to cover these gaps, and that cost flows through to the tariff consumers pay.
Managing Director and CEO Dr. Joseph Siror frames the issue as a structural one built into how Kenya buys power. Under the take or pay model governing most of Kenya’s power purchase agreements, the utility commits to paying generators whether or not it actually needs their output at a given moment. Combined with rising VRE penetration, Siror says that has driven up the overall cost of keeping the grid stable, not just the cost of the renewable energy itself.
The numbers check out against regulatory data
Kenya Power’s 20 percent capacity figure lines up closely with data published by the Energy and Petroleum Regulatory Authority. As of June 2025, EPRA recorded 435.5MW of interconnected wind capacity and 210.3MW of interconnected solar capacity, a combined 645.8MW against total interconnected installed capacity of 3,192MW, putting wind and solar at just over 20 percent of firm grid capacity. That matches the threshold Kenya Power is now flagging as a stability concern.
On generation rather than capacity, EPRA’s most recent annual figures show a more moderate picture: wind supplied 13.18 percent and utility scale solar 3.27 percent of total electricity generated in the year to June 2025, a combined 16.45 percent. The gap between that annual average and Kenya Power’s 34 to 36 percent figures reflects timing. VRE output is not evenly spread across the day, and its share of the mix swings higher during specific demand windows, which is precisely the volatility Kenya Power says the grid now has to absorb.
| Metric | Value | Source |
|---|---|---|
| VRE share at peak demand (1,900MW) | 34% | Kenya Power, August 2026 |
| VRE share at low load (1,200MW) | 36% | Kenya Power, August 2026 |
| Wind and solar share of firm grid capacity | Over 20% | Kenya Power, August 2026 |
| Wind and solar share of interconnected installed capacity | 20.2% | EPRA, June 2025 |
| Wind share of annual generation | 13.18% | EPRA, June 2025 |
| Utility scale solar share of annual generation | 3.27% | EPRA, June 2025 |
| Recommended VRE firm capacity limit | 15% | Kenya Power, citing global benchmarks |
Sources: Kenya Power press release, August 11 2026; EPRA Energy and Petroleum Statistics Report, financial year ended June 2025
Curtailment already happens, just not to wind
EPRA’s data offers a useful complication to Kenya Power’s argument. The regulator’s most recent report shows that geothermal, not wind or solar, has borne the brunt of grid curtailment. Kenya cut 668.7 gigawatt hours of geothermal output in the year to June 2025 because low nighttime demand left the system with more baseload power than it could use, while no wind energy was curtailed at all during the same period. That points to a mismatch between the country’s generation portfolio and its demand profile that runs deeper than variable renewables alone, even as VRE penetration adds a second, faster moving layer of volatility on top of it.
Where Kenya Power wants investment to go instead
Siror points to battery storage as the standard fix for intermittency, but flags its own limitation: batteries still need charging, and if wind and solar output dips for an extended stretch, there is nothing to charge them with. His preferred alternative is doubling down on geothermal and hydro, sources that can hold steady output and recover quickly once intermittent generation drops away.
KenGen, whose generation portfolio leans heavily on geothermal, supplied 58.97 percent of the country’s electricity in the year to June 2025, according to EPRA. Geothermal alone accounted for 39.51 percent of total generation, more than wind, solar and hydro combined.
Kenya’s installed geothermal capacity has stayed flat at 943.7MW since 2023, even as the country works toward a government target of generating 100 percent of its electricity from renewable sources by 2030, a goal that will require growing every renewable category, including the variable ones Kenya Power is now urging caution on.
The tension ahead
Wind and solar remain the cheapest new generation to build, and Kenya’s climate commitments depend on scaling them up. Scaling them without matching investment in flexible backup, storage or fast responding baseload risks pushing costs onto consumers through exactly the kind of standby dispatch charges Kenya Power is warning about.
How the Energy Ministry and EPRA balance that tension in future power purchase agreements will shape whether Kenya’s renewable growth story continues on its current trajectory or gets recalibrated around grid stability limits.
