The Kenyan stretch of the Great Rift Valley is breathtaking. The vast plains between the two hillsides teem with wildlife, creating the Mara-Serengeti wildebeest migration, one of the world’s largest animal migrations. Alkaline lakes in the East African rift system are home to graceful flamingos, pink wonders that attract visitors from around the world and are a vital cog in Kenya’s booming tourism industry.
But it is what lies beneath the valley floor that has had a literally seismic impact on Kenya in recent years; vast geothermal resources that make the country a world leader in clean energy.
Peketsa Mangi is the general manager of geothermal development for the country’s power generating company, KenGen. “We are lucky that the African rift passes through Kenya,” he told me during my visit last week. “We were in the right place with several volcanic centres. Olkaria is one of these centres.”
Mangi and I sit in a gazebo overlooking a spa pool that uses salt water, a byproduct of the geothermal development process. Visitors from all over Kenya come to enjoy the pool’s “healing” properties. With a power plant humming nearby, my first visit to the heart of Kenya’s geothermal energy production becomes a lesson in what’s going on beneath our feet.
According to the Geological Society, the Somali and Nubian tectonic plates pulled in opposite directions about 25 million years ago; The surface between the two fault lines sank, pushing magmatic fluids closer to the Earth’s surface, creating the famous rift, a wide valley stretching across the Earth. 6,400 km from Jordan to Mozambique. Below the valley, water easily percolates and comes into contact with hot rocks 1-3 km below the surface, creating a mixture of superheated water and steam of 75% and 25% respectively, with an average temperature of 300C (572F) and a pressure of 1,000 PSI. . These turned out to be perfect conditions for producing geothermal energy.
“This is the steam we use to drive turbines that produce electricity. It’s tough down there and that’s where we’re going,” says Mangi. “A dangerous but necessary task.”
Mangi has been observing the behavior of the valley for 27 years and knows exactly where to drill a well that will provide geothermal energy. “Kenya has developed the capacity for precise geoscientific studies that help us identify potential areas to drill. Exploration and drilling are cost-intensive endeavors and investors do not want to go into a new area without confirmed viable resources,” he says.
The beginnings of geothermal energy began in 1904 in the small settlement of Larderello, Italy. The small plant provided only 10kW of energy; This was enough to power five bulbs. Since then, some countries have dug deep to tap similar resources. The United States, Indonesia, Philippines, Turkey and New Zealand are the world’s five largest producers of geothermal energy.
The search for underground energy in Kenya began about 70 years ago but stalled almost immediately. In 1956, the government specifically drilled two wells at a depth of 950 meters and 1,200 meters respectively to harness geothermal energy. “The average temperature was 235°C (445°F), but since the surrounding area was a bit solid, the wells could not discharge due to poor permeability,” says Mangi.
Then came the oil crisis of the early 1970s, and once again Kenya looked underground for an answer. Global organizations, including the United Nations Development Programme, the World Bank and the Japan International Cooperation Agency, have stepped in to provide financial and technical support for further research. In 1971, a well was opened and discharged. Mangi says everyone is excited again. Between 1981 and 1985, Kenya had an installed capacity of 45MW, with the first three power plants in Olkaria.
“We don’t know where the country would be if the oil crisis had not accelerated this process,” says Mangi. “Geothermal is available 24/7, 365 days a week. Since we use water that has accumulated deep in the soil for thousands of years, it is not affected by climate changes. The alternative would have been the installation of polluting diesel generators. “This is our contribution to a cleaner world.”
Now here in Olkaria, near the flower-growing town of Naivasha, 56 miles (90 km) from Nairobi, there are close to 300 geothermal wells that provide steam to power turbines in five geothermal power plants operated by KenGen.
The total capacity of power plants and 15 wellheads is 799 MW. With additional geothermal energy produced by independent energy producers, Kenya’s total geothermal energy capacity is 988.7 MW, placing the country sixth globally (and first in Africa) in terms of geothermal energy development.
As a result, Kenya gets up to 91% of its energy from renewable sources: 47% geothermal, 30% hydroelectric, 12% wind and 2% solar power. The country hopes to switch entirely to renewable energy by 2030, and KenGen says it has the potential to increase the country’s capacity to up to 10,000 MW of geothermal energy. This would more than meet the peak demand in Kenya, which currently stands at around 2,000 MW. Peak time consumption in the UK is approximately 61,000 MW.
There are many wells in the Hell’s Gate national park, which inspired the movie The Lion King. Antelopes, giraffes, zebras and buffalos patrol the park; all roam free and are oblivious to the enormous energy trapped beneath their hooves and delivered to power plants through a labyrinth of high-pressure pipe systems averaging 120 kilometers long.
“Geothermal energy is clean and does not harm wildlife because animals have adapted to this system,” says Gastone Odhiambo, a security guard at power plants. “These pipes send steam at 180C (356F) to turbines to produce 11 kilovolts of electricity, which is then boosted to 220 kilovolts to travel long distances. You need a sober mind as one mishap can bring the country to a halt.”
Odhiambo’s childhood home in western Kenya had no electricity. “I grew up in the dark,” he tells me in the factory control room filled with switches, dials and strobe lights. “Helping to produce clean energy that can last for years is a heavy responsibility. When you understand the process, when you understand how your tasks impact the day-to-day running of the economy, you remain humble.
Kenyan President William Ruto is currently leading an African campaign to wean the continent off fossil fuels. In September last year, a declaration was signed calling for reform of international finance and condemning the global north for its distorted global financial system that makes it difficult for Africa to tap into vast renewable energy resources.
“Despite Africa having an estimated 40% of the world’s renewable energy resources, only $60 billion, or 2% of the $3 trillion in renewable energy investment, came to Africa in the last decade,” the statement said.
While Kenya and the rest of Africa await fiscal reforms, for the team working on the geothermal power plants in Olkaria it is a rewarding task, as Mangi sums it up: “A good day here is when the whole process works like clockwork. All the scientific work and the financial resources “When it is poured into the ground, the well is opened and emptied, which means it provides power to the country. You feel that the investments are being used well. And there are many good days like this.”