Kenya looks underground for power

In frica's Rift Valley, a giant fissure in the Earth's crust running 9,500km from Lebanon to Mozambique. The plumes of escaping steam, and bubbling lakes, hint of volcanic turmoil beneath the surface. Experts from the United Nations say if this geothermal energy were harnessed, it could provide power to some of the world's poorest nations. Eritrea, Ethiopia, Djibouti, Uganda, and even Zambia have the potential to tap in. But so far, Kenya is the only nation which has made headway.

Kenya's Ol Karia station is the continent's biggest geothermal power-generating plant. It takes its name from a nearby volcano, which erupted 150 years ago and is still active. Here there are 22 wells across the site, piercing the Earth's crust, and tapping into rock as hot as 345C deep below the surface. Water pumped into the well produces steam, which powers the turbines.

But even Kenya has been slow to exploit this resource. Potential sites could be identified and millions of dollars spent drilling wells, but the result could be zero. The consistency of heat or the rock type may not be suitable for geothermal electricity. This unpredictability makes African governments nervous. Unep, through its Global Environment Facility, is trying to help with the costs and to encourage private investors.

Geothermal energy should be a potential source of power in other parts of the word. The Pacific Rim, circled with volcanoes, seems like one obvious spot for exploitation. Even the U.S. should have the potential to exploit this resource.