Residents living along the shores of Lake Kivu in central Africa have always appreciated – and feared – its power. In Swahili, the word mazuku, or “evil wind,” refers to pockets of deadly, odorless gas that seep from the lake, killing whatever happens to be in its path. Two hundred and fifty feet below the surface of Lake Kivu, which covers an area of roughly 1000 square miles on a natural border between Rwanda and Congo, some 250 cubic kilometers of carbon dioxide is lurking, along with another 65 cubic kilometers of methane. Every so often, some escapes.
Yesterday, the Guardian’s east Africa correspondent Xan Rice wrote about Rwanda’s efforts to harness some of that deadly potential for clean energy. A pilot project by the state’s Kibuye Power is extracting methane from the lake and funneling it to an onshore plant to be converted into electricity. Currently, Kibuye is producing less than 4MW from Lake Kivu’s gas, but has its sights set on ramping that up to some 50MW within a few years. Rice writes:
Within two years, the government hopes to be getting a third of its power from Lake Kivu, and eventually aims to produce so much energy from methane to be able to export it to neighbouring countries. “Our grandfathers knew there was gas in this lake but now have we proved that it can be exploited,” said Alexis Kabuto, the Rwandan engineer who runs the $20m Kibuye project. “It’s a cheap, clean resource that could last us 100 years.”
Other investors in Kivu’s methane include Contour Global, a U.S.-based company that specializes in energy generation in new or under-served markets. Last year, the company signed a $325 million agreement with the Rwandan government to extract methane and develop a 100MW energy plant on the lake.
The danger that Kivu’s gas reserves pose is serious, thanks to a geological phenomenon, as horrifying as it is fascinating, called a limnic eruption. Limnic eruptions occur in lakes that are in volcanic regions, when some disruption — an earthquake or even heavy rains — send gases in the lakes’ depths to rise toward the surface. The release of pressure causes a tsunami effect in the lake, and waves filled with carbon dioxide sweep to shore where they release carbon dioxide into the atmosphere in lethal amounts. Cameroon is home to the only other two “exploding lakes” that have been known to erupt, one in 1984 and one in 1986. The second event, at Lake Nyos, released carbon dioxide that smothered nearly 2000 people.
Scientists don’t believe a limnic eruption is imminent at Lake Kivu; the lake’s water is not yet as saturated with gas as either of the Cameroon lakes were when they exploded. But the stakes at Kivu are also higher: it’s a great deal larger than Nyos, and some two million people live on its shores. (In addition to the mazuku, Kivu has, freakishly, been reported to “swallow” people in random gas pockets.) The extraction of methane, which is explosive on contact with the air, could help stabilize the lake, both by ridding it of that gas and releasing of some carbon dioxide in the process.
It could certainly help Rwanda’s chronic power shortages, as described here in an opinion piece by Khadija Sharife that appeared last year in African Business:
One reason why Rwanda is confined to primary agricultural initiatives is the acute shortage of electricity. National power plants generate just 60MW, while the country — dependent on imported oil and hydroelectric power — regularly experiences frequent blackouts. Power is accessed by 6 per cent of the population, chiefly residents of urban areas, but four out of five citizens live in rural areas.
But Sharife goes on to caution that methane extraction is not necessarily a wise solution, both because of the lack of government regulation on the fledgling industry and its potential to further destabilize an already precarious ecology. Furthermore, Sharife points out, Rwanda and Congo have not exactly had smooth relations. Fighting has erupted near Kivu in eastern Congo this summer, and Sharife fears the dozen or so proposed extraction platforms — which could constitute one of the largest foreign investments in Rwanda — would be vulnerable to attack if things get more heated.
Still, there is something inspiring about such a force of nature being harnessed in a way that could reduce Rwanda’s dependence on imported energy, and increase the quality of life for so many people — if, and it’s still a pretty big if — it gets done right.