A faint smell of sulphur, a shrill hiss of gas and a Rift Valley panorama punctuated by 30 pillars of steam mark the frontline of renewable energy growth in Kenya.
This is the boundary between Hell’s Gate national park and the geothermal plants that are increasingly powering one of east Africa’s fastest-growing economies.
Giraffes wander close to the giant pipes that snake across the landscape, a reminder this is also a border between an old model of development reliant on foreign safaris and a new drive to leapfrog the fossil-fuel phase of growth.
In recent years, Kenya has been a frontrunner in expanding access to electricity. Since 2010, the proportion of the 44 million population with power has reportedly surged from one in five to three in five. This is largely thanks largely to steam from the subterranean depths.
Hell’s Gate is named after the sulphurous hot springs that bubble up in this part of the Rift Valley, a 3,500-mile fault line that is slowly pulling the African continent apart and bringing underground heat closer to the surface.
Engineers tap the energy by drilling up to 5,000 metres into the earth, then injecting water that returns to the surface as steam to drive turbines. As long as the water is carefully recycled, the energy is virtually renewable. Emissions of methane and other greenhouse gases are released in the process, but the impact on the climate per kilowatt hour is between a fifth and a ninth that of burning fossil fuels.