The world’s biggest hydroelectric scheme, a project to harness the Congo River and power the African continent, is to be debated today in Botswana by multinational energy companies and development banks.

The Grand Inga power station would capture the intensity of water flowing through rapids at Inga Falls, in the Democratic Republic of Congo (formerly Zaire). Located near the mouth of the Congo River, with an output of 39,000 megawatts, Grand Inga would generate twice the power of China’s Three Gorges dam. Three electricity superhighways would deliver power south to Angola, Botswana and South Africa, west towards Nigeria and north to Egypt and, ultimately, southern Europe.

André Caillé, former chairman of Hydro-Québec and currently chairman of the World Energy Council, which is promoting the project, said Grand Inga would produce very cheap power at a cost of just “three cents per kilowatt hour”. So large are the economies of scale that power delivered from Grand Inga to the Italian border would cost less than the current market price of electricity in Italy today.

Geopolitical and logistical barriers have kept the Grand Inga megaproject, which might cost $80 billion (£41 billion), away from the starting gate. The hydropower potential of the Congo is legendary. Fed by tropical rainforest, its water flow eclipses the Nile. Two studies of Grand Inga, including a feasibility study by Electricité de France in 1997, concluded that it was economically viable and technically feasible.

War and insurrection in Congo and neighbouring Rwanda have intervened, while the equipment in two early power stations, Inga 1 and Inga 2, has deteriorated.

Political change and global warming have recently revived interest in Grand Inga. The election of Joseph Kabila as president of Congo, in the first freely contested election in 40 years, has reignited the hopes of big mining companies that they could soon embark on large-scale development of Congo’s vast mineral wealth. Having declared its objective to lift Africa out of poverty, the G8 group of nations is looking for projects that can kick-start development. A supply of cheap energy is critical and concern about carbon emissions is focusing attention on hydroelectricity.

Sir David King, the British Government’s chief scientific adviser and a leading voice in the climate change debate, this week gave support to Grand Inga. He said it would be a catalyst for economic growth and improved skills in sub-Saharan Africa where some 500 million people live without electricity.

“The speed brake on economic growth is [lack of] energy,” he said. “In South Africa, the limit is currently at 6 per cent.”

The promoters of Grand Inga are seeking political consensus, not cash; the site is already profitable said Mr Caillé. At Inga, the Congo River falls 100 metres over a distance of 15 kilometres. “We don’t need to build a dam, the dam is already there,” he said.

With the flow

52 the proposed number of power generators in the Grand Inga project

39,500 megawatts of power expected to be produced

26,400 cubic metres per second water flow

$30-$80bn the cost of the project, depending on scale

Source: World Energy Council

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