Kenya and geothermal energy

The Times Eureka Magazine
Hell’s Gate, Kenya

Hundreds of pipelines snake across the petrified lava flows, scrub-covered hills and steep gorges of Hell’s Gate, a prehistoric landscape dotted with steel chimneys spewing columns of sulphurous white steam into the air.

This collision of stark natural beauty and industry is the birthplace of Africa’s green power revolution, nestling in the 3,500-mile Great Rift Valley. In the floor of the fissure, the Earth’s crust is thinner, the ground closer to its molten core.

Hell’s Gate is the African home of geothermal energy. Wells drilled two miles down pipe superheated water to three power plants where it turns into steam, spinning turbines to produce clean, green and renewable electricity. The cooled water is then injected back into the wells, producing more steam and more energy. The power stations here at Olkaria produce 163 megawatts, 13 per cent of Kenya’s total generating capacity. “You need water, heat and some cracks,” Peter Ouma, manager of the steam fields, says. “Here, if you dig a pit latrine you get steam.”

Kenya is an unusually green energy producer among African countries, which tend to rely on imported fossil fuels. Hydroelectricity accounts for 60 per cent of its power but drought, deforestation and silting of dams are squeezing capacity, leading to increased reliance on expensive diesel. Despite leasing diesel generators, East Africa’s biggest economy can barely keep the lights on; parts of the capital Nairobi have recently been in darkness every other day.

According to Peerke de Bakker, an energy expert at the Nairobi regional headquarters of the United Nations Environment Programme (UNEP), the time is ripe for geothermal energy in Kenya and other Rift Valley countries.

“The idea is that by 2018 Kenya alone will have developed over 1,000MW of geothermal. But the African Rift is much bigger than Kenya,” he says, adding that the entire valley could generate about 7,000MW. “It will mean indigenous power for the countries of the Rift Valley, increasing their own supply security, reducing the drain on foreign exchange and of course it has a [positive] environmental impact,” he says.

Tapping the Earth’s heat is not a new idea. Italy built its first geothermal power station (still running today) in 1904, and Iceland is powered almost entirely by geothermal energy. “Once the well is there the energy is basically free,” de Bakker says. But, he adds, “when you fail, it’s an expensive mistake, up to $5 million”.

Those upfront costs and uncertainties are being partly borne by the government’s newly formed Geothermal Development Company (GDC). Dr Silas Simiyu, the chief executive, is tasked with finding suitable geothermal sites as well as investors to exploit them.

“We are not going to wait for an investor to come and do the drilling,” he says. “We will do it ourselves and [undertake] the feasibility study that we can take to investors.”

Simiyu’s state-owned enterprise, like those of many African governments, is looking to China. Much of the GDC’s $75 million (£45 million) start-up cash will go on relatively cheap Chinese-made rigs to drill exploratory wells. Already, two leased rigs manned by Chinese are drilling in Hell’s Gate.

Elsewhere in the Rift, an $18 million fund put together by the World Bank and UNEP will pay for more high-tech exploration — in Kenya, as well as in Djibouti, Eritrea, Ethiopia, Tanzania and Uganda. The first well, to be drilled in Lake Assal, Djibouti, will be the start of a 50MW plant.

If Hell’s Gate is where Africa’s green energy revolution began, an important part of its future lies hundreds of miles to the north on a desert plain of rock and dust, framed by towering mountains, where the hot wind blasts day and night.

Three years from now, this inhospitable wilderness is set to become Africa’s biggest wind farm, with 365 turbines and a capacity of 300MW. The site is “a wind energy developer’s dream”, says Carlo van Wageningen, chairman of the Dutch-led Lake Turkana Wind Power consortium behind the plant.

That dream is backed by investors and loans from the African Development Bank and others, which is just as well as it won’t come cheap. The wind farm itself will cost $636 million, and another $260 million will be needed for 266 miles of high-voltage transmission lines to link it to Kenya’s national grid.

It should all be worth it. Under the terms of a 20-year deal with the Kenya Power and Lighting Company — the utility group responsible for electricity distribution — the consortium will be paid $0.10 for each kilowatt-hour of energy, roughly half what Kenya is shelling out for energy from emergency diesel generators. Kenya will also benefit from carbon credits worth around $14.5 million a year, Van Wageningen reckons.

Further advanced though rather less ambitious is Kenya’s first — and so far only — wind farm, strung along the rolling peaks of the Ngong Hills on the Rift Valley’s eastern escarpment.

The six 50m tall turbines began feeding 5.1MW of power into the national grid this summer, and Hezron Ng’iela, an engineer at the state power company KenGen, says it is proof Kenya can harness the wind. “We have a lot of wind potential, probably enough to sustain us for a number of years,” he says.

Wind farms in Egypt and Morocco generate most of the continent’s 563MW of wind power, although this is equivalent to less than a fifth of what Britain alone generates. That is set to change as governments across Africa begin to realise the green energy potential trapped beneath the earth and in the wind.

http://www.thetimes.co.uk/tto/others/article1844345.ece