Mount Nyiragongo glowers over this forsaken city, a sullen and capricious king crowned with thunderheads. To most people here this volcano with a vast lake of fire in its belly is a slumbering menace. Twice in 31 years, it has hurled lava toward the city, most recently in 2002, when it left thigh-high drifts of black rock where neighbourhoods used to be.
Swiss scientists are helping the government of Rwanda to extract potentially lethal methane from a dangerous lake for much needed electricity production. The threat in the Lake Kivu area comes from billions of cubic metres of gas dissolved deep underwater that could kill large numbers of people if it were to escape. The aim of the Rwandan government project is to extract methane from the lake, which straddles the border with the Democratic Republic of Congo, to ensure secure power supplies in the region for decades. The authorities also want to reduce the risk of a deadly gas eruption.