The Steam Under the Rift

You can cycle to it, which is the strange part. Hell's Gate is one of the few Kenyan national parks with no meaningful predator population, so the gate at Elsa hires out bicycles and you ride the valley floor between red cliffs with zebra and eland grazing beside the track. Then the track bends, and running over your head on steel gantries are insulated pipes the diameter of a car, carrying superheated water and steam from wellheads scattered across the scrub to the turbine halls at Olkaria. Nobody has fenced them off from the wildlife. The zebra graze under them.

This is the largest geothermal complex in Africa and it is the backbone of the Kenyan grid. According to the Energy and Petroleum Regulatory Authority, geothermal was the country's leading source of electricity in the financial year to June 2025 — 5,718 gigawatt-hours, 39.5 per cent of total generation of 14,472 GWh, with hydro second at 24.2 per cent and wind third. Around four fifths of the grid ran on renewables. That is not an aspiration or a pledge for 2050. It is a meter reading.

What was wrong with rain

For most of its independent history Kenya generated electricity from water — the Seven Forks dams on the Tana, chiefly — and water in East Africa is a function of two rainy seasons that fail regularly. When they failed, output fell, and the utility filled the hole with emergency diesel bought at whatever the world price happened to be, passed straight through to consumers as a fuel-cost surcharge on the bill. A drought was therefore not only a drought. It was a tariff rise, an industrial slowdown and a balance-of-payments problem at the same time.

Olkaria, 1981

The alternative had been sitting under the Rift Valley the whole time, and it took thirty years to prove. Two exploratory wells went down at Olkaria as early as 1956 and found rock at 235°C, and nothing came of them. From 1970 the UN Development Programme worked with the Kenyan government and the regional power company across the ground between Lake Bogoria and Olkaria, narrowing the search to about eighty square kilometres; funded drilling began in 1973. The first 15-megawatt unit was commissioned in June 1981 — the first geothermal power station anywhere in Africa. A second followed in November 1982 and a third in March 1985, for 45 MW in total. The station is still running, now under KenGen, which reports an availability factor above 95 per cent across its life — for a plant of that age, close to absurd.

A geothermal field is not discovered so much as bought — one very expensive hole at a time, and a certain number of the holes come up dry. That, and not the engineering, is what kept the Rift underused for thirty years.

Who pays for the dry holes

Here is the economics that had stalled everything. A deep geothermal well costs several million dollars and takes weeks to drill, and until it is finished nobody knows whether it will deliver commercial steam. A wind developer can measure the wind for a year for a rounding error; a solar developer can look up the irradiance. A geothermal developer has to spend most of the capital cost of the project before finding out whether there is a project — and private lenders will finance a power station but not a lottery ticket. So in 2008 the Kenyan government created a company to buy the lottery tickets itself. The Geothermal Development Company is a state parastatal that does the part nobody else will: survey the field, drill the wells, prove the resource, then sell the steam to whoever wants to build a turbine on top of it. The risk sits on the public balance sheet, diversified across a whole country's drilling programme rather than concentrated in one investor's single hole. It has a name in the sector now, the GDC model, and its test case is Menengai, the caldera above Nakuru, where the first well was spudded in February 2011 and the first phase was carved into three 35 MW contracts for independent producers. The first of them, Sosian, began delivering to the grid in 2023 — twelve years after the rig went in, which is the honest measure of how slow this business is even once the risk problem has been solved.

The wellhead trick

The second Kenyan idea was smaller and cleverer. A conventional geothermal station is built once the field has been drilled out, and every well sits idle — earning nothing, paying interest — until the turbine hall is finished, which may be five years later. KenGen instead began putting small modular generators directly on individual wellheads: a few megawatts each, delivered as a package, generating within months of the well being completed. The pilot went onto a single well, OW-37A in the Olkaria East field, in February 2012; a fleet followed, and KenGen now runs fourteen wellhead units at Olkaria adding up to about 81 MW, plus one more at Eburru — roughly a large plant's worth of capacity that would otherwise have been steam venting into the sky. They also let you use awkward wells too far from a main plant to be worth piping in. Delegations now come to Olkaria to look at them.

The bill at Olkaria

None of this happened on empty land. The expansion of the field for the 140 MW Olkaria IV plant moved four Maasai villages, about a thousand people, off ground they had lived and grazed on, onto plots of a little over a third of a hectare each in a new settlement that appears in the project documents under the name RAPland — after the Resettlement Action Plan that produced it. In October 2014 community leaders took a complaint to the World Bank's Inspection Panel, the Bank being a major funder. The Board authorised an investigation in February 2015; the Panel reported that July and found the Bank had not complied with its own rules, in particular by failing to trigger its policy on Indigenous Peoples. In October 2015 the Board approved a mediated process to settle what was owed, and an agreement with KenGen was signed in May 2016. The houses at RAPland are, by most accounts, better built than what they replaced. That was never the complaint. The complaint was about grazing, about graves, about a community split over who counted as displaced, and about the order in which people were asked.

Both halves of that are true at once and it is worth holding them together, because the Rift is going to keep being drilled — Menengai is at a fraction of its assessed potential, and the fields further north at Baringo-Silali have barely been touched. Kenya built something that a great many richer countries have talked about and not managed: a grid that mostly does not burn anything, financed by putting the exploration risk somewhere it could be carried. The steam under the valley floor was always free. Everything above it, including the arguments, had to be paid for.