by The Kenyan stretch of the Great Rift Valley is breathtaking. Large plains between the two escarpments are teeming with wildlife, creating one of the largest animal migrations in the world – the Mara-Serengeti wildebeest migration. The alkaline lakes in the east African rift system are home to elegant and graceful flamingos, pink wonders that attract visitors from around the world and are a vital cog in Kenya’s thriving tourism industry.
But it’s what lies beneath the valley floor that has literally had a seismic impact on Kenya in recent years – vast geothermal resources that have put the country at the forefront of clean energy.
Peketsa Mangi is the general manager in charge of geothermal development at KenGen, the country’s energy generation company. “We are lucky that the African rift runs through Kenya,” he told me when I visited last week. “We happened to be in the right place with some volcanic centers. Olkaria is one of these centres.”
Mangi and I are sitting in a gazebo overlooking a spa pool that uses brine, a byproduct of the geothermal development process. Visitors come from all over Kenya to enjoy the “healing” properties of the pool. With a power plant humming nearby, my first visit to the epicenter of Kenya’s geothermal power generation is a lesson in what’s going on beneath our feet.
According to the Geological Society, the Somali and Nubian tectonic plates pulled apart in opposite directions about 25m years ago, with the surface between the two fault lines sinking and bringing magmatic fluids closer to the Earth’s surface and at the creation of the famous rift, a huge valley that runs. 6,400km from Jordan to Mozambique. Below the valley, water easily percolates and comes into contact with hot rocks found 1-3km below the surface, creating a mixture of superheated water and steam at 75% and 25% respectively, with temperatures averaging 300C (572F) and pressures of 1,000 PSI. . These, it turns out, are the perfect conditions for generating geothermal energy.
“This is the steam we’re using to run the turbines that generate electricity. It’s rough down there, and that’s where we go,” says Mangi. “A dangerous but necessary mission.”
Mangi has observed the behavior of the valley for 27 years and knows exactly where to drill a well that will provide geothermal power. “Kenya has developed the capacity for precise geological studies that help us identify potential drilling areas. Exploration and drilling are cost-intensive endeavors and investors don’t want to go to a fresh field without confirmed viable resources,” he says.
Geothermal energy began in the small settlement of Larderello in Italy in 1904. The small plant provided only 10kW of energy, just enough to power five light bulbs. Since then, several countries have dug deep to exploit similar resources. The top five producers of geothermal power in the world are the United States, Indonesia, the Philippines, Turkey and New Zealand.
In Kenya, the search for underground energy began almost 70 years ago, but stopped almost immediately. In 1956, the government drilled two wells specifically to harness geothermal power, at depths of 950 meters and 1,200 meters respectively. “The average temperature was 235C (445F) but the wells were not released due to poor permeability as the surrounding area was somewhat solid,” 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 undertaken to provide financial and technical support for further exploration. In 1971, a well was drilled and released. Everyone was excited again, says Mangi. Between 1981 and 1985, Kenya had an installed capacity of 45MW through the first three power plants in Olkaria.
“We don’t know where the country would be if this process had not been accelerated by the oil crisis,” says Mangi. “Geothermal is available 24/7 for 365 days. It is not affected by climate fluctuations because we are using water that has accumulated deep in the ground over the course of millennia. The alternative was the installation of diesel generators which pollute the environment. This is our contribution to a cleaner world.”
Now, here at Olkaria, near the flower town of Naivasha 56 miles (90km) from Nairobi, there are close to 300 geothermal wells providing steam that runs turbines in five geothermal power plants operated by KenGen.
The power plants and 15 wellheads have a combined capacity of 799MW. With additional geothermal power generated by independent power producers, Kenya’s total geothermal power capacity is 988.7MW, placing the country sixth in the world (and first in Africa) in terms of geothermal power development.
As a result, Kenya sources up to 91% of its energy from renewable sources: 47% geothermal, 30% hydro, 12% wind and 2% solar. The country hopes to transition completely to renewable energy by 2030, and KenGen said the country has the potential to increase its capacity to as much as 10,000MW of geothermal energy. That would be more than peak demand in Kenya, currently around 2,000MW. Peak time consumption in the UK is around 61,000MW.
A number of wells sit within Hell’s Gate national park, the location that inspired the film The Lion King. The park is patrolled by antelope, giraffe, zebra and buffalo, all roaming freely and oblivious to the vast energy trapped beneath their hooves and delivered to the power stations through a labyrinth of high-pressure piping system 74 miles (120km).
“Geothermal power is clean and does not harm the wildlife as the animals have adapted to this system,” says Gastone Odhiambo, safety officer at the power stations. “These pipes are delivering steam to the turbines at 180C (356F) to produce 11 kilovolts of electricity which is then stepped up to 220 kilowatts to travel long distances. You need a smart mind because one disaster can bring the country to a standstill.”
There was no electricity in Odhiambo’s childhood home in western Kenya. “I grew up in the dark,” he tells me at the plant’s control room full of switches, dials and strip lights. “It’s a big responsibility to help generate clean energy that could last for years. When you understand the process, how your tasks affect the day-to-day running of the economy, you stay humble.”
The president of Kenya, William Ruto, is now leading the African campaign to wean the continent off fossil fuels. In September last year, a declaration was signed that called for the reform of international finance and resolved the global north to the skewed global financial system that makes it difficult for Africa to take advantage of its vast renewable energy resources .
“Despite having about 40% of the world’s renewable energy resources in Africa, only $60bn or 2% of the $3tn renewable energy investments went to Africa in the last decade,” read the declaration.
While Kenya and the rest of Africa are waiting for the financial reforms, it is a rewarding task for the team working at the geothermal plants in Olkaria, as Mangi sums it up: “A good day here when the whole process works like clockwork. When all scientific studies and financial resources are poured into the ground, a well is drilled and it releases, that is the power of the country. You feel that the investments are put to good use. And there are many good days like that.”
