Lake Kivu, which sits on the border of Rwanda and the Democratic Republic of Congo, lies above Africa's continental rift zone, a geologically active region where Earth's tectonic plates are very slowly being pulled apart. That activity has lead to a large buildup of dissolved methane and carbon dioxide in the deep waters of the lake, but plans are in place to start pumping the gas out of the lake to generate electricity -- enough to double Rwanda's current electricity capacity.
Phys.org reports, "Levels of carbon dioxide (CO2) and methane are large and dangerous enough to risk a sudden release that could cause a disastrous explosion, after which waves of CO2 would suffocate people and livestock around," explained Matthew Yalire, a researcher at the Goma Volcano Observatory, on the lake's DR Congo shore.
"Right now the lake is stable, but for how long?" asked Yalire, explaining that extracting the gas could help stabilize the lake and avoid an explosion.
Power company ContourGlobal is currently building a platform to start pumping the gas out of the lake depths. The technology will suck the trapped gases -- no drilling involved -- to the surface where it will be collected. The methane and CO2 are then separated and the methane is sent to a plant onshore, while the CO2 is redissolved and pumped back into the depths of the lake.
The project leaders say the process has no adverse effect on the lake and the plants and animals that live in and around it.
The first phase of the project called KivuWatt will produce 25 GW of electricity, eventually growing to 100 GW, almost doubling Rwanda's current capacity of 115 GW. This project is part of the Rwandan government's plan to expand access to electricity from the 17 percent of the population who currently have access to 70 percent of the population by 2017.
The risk of letting the gases continue to build is a big one. In the 1980s, two lakes in Cameroon that have similar levels of gasses both had limnic explosions which claimed over 1,700 lives. About 2 million people live close to the lake shore, so the an extraction project is necessary. This one just also offers the population a clean source of energy.