One of the more vivid memories of my childhood was hearing about the 1985 disaster at Lake Nyos in Cameroon. In case you forgot, Lake Nyos was naturally super-saturated with dissolved carbon dioxide and other gasses. When disturbed by an earthquake, the lake literally “fizzed” out millions of tons of CO2 like the opening of a soda can. Being heavier than air, the CO2 spilled over the lake’s banks and down a valley suffocating over 1700 people and countless animals over the course of an hour or two. Anything that wasn’t a plant died.
It turns out there are two other lakes in the world which have smiler saturations of gas and therefore share the potential for this kind of disaster. One is another minor lake in Cameroon and the other is the vastly larger and more significant Lake Kivu between Rwanda and the Democratic Republic of the Congo. Lake Kivu (upon whose shore I sat researching this post) is 2000 times larger than lake Nyos and has more than two million people in its immediate vicinity. It is not only saturated CO2 but, it turns out, is also saturated with methane. It remains stable, but being in an area of seismic activity, it’s only a matter of time before a volcanic event or earthquake could disturb the lake enough to release these gases. In fact, scientists say that the phenomenon, known as a limnic eruption, is expected to occur at some point in the next 100 or so years.
However, there might be a solution that would both prevent disaster and create tremendous economic opportunity for an impoverished nation at the same time.
Enter Contour Global.
In 1992, A French team figured out that they could reduce the CO2 content of Lake Nyos by simply lowering a free standing pipe into the water and pumping water from a deep point to the surface. CO2 would fizz out with such speed it would pull more water behind it, allowing the pump to be turned off and creating a tremendous fountain of water and gas blasting into the sky – just like taking the cork out of a shaken – up champagne bottle. The CO2 released would, in theory, come up with managable volume so that it would prevent a more catastrophic release sometime later.
Contour Global, a power development company with operations around the world, observed this technique and figured it could be applied to Lake Kivu, with the added commercial benefit of collecting methane, (which can be burned to produce electricity). The project is known as KivuWatt and is scheduled to start operating in early 2012.
Theoretically, by simply sticking a pipe into the water, the company could extract some of the estimated 65 cubic kilometers of methane in the lake to produce as much as 100MWs of electricity for a country whose current total production is a mere 69MW. Even better, half of Rwanda’s current electricity production comes from diesel generators, a dirty and expensive proposition when compared to the relatively clean and cheap burning of methane – a powerful greenhouse gas which breaks down into CO2 and water vapor when burned. Diesel generation could be greatly reduced as Rwanda improves its electricity grid to bring on power coming from the project.
Granted, KivuWatt is not an emissions-free source of electricity. However, according to Global Post (I was unable to get in touch directly with KivuWatt while in the country) and other sources, the CO2 gas which naturally comes up with the methane will be separated and re-sequestered into the lake at a less dangerous depth. This process happens to be the most complicated piece of the puzzle but means that the KivuWatt project should have about the same CO2 impact as a typical natural gas power plant, and perhaps even less given the possibility to eliminate the burning of diesel.
Most importantly, giving Rwandans access to cheaper, more reliable electricity means more opportunity to bring themselves out oft he grip of poverty and into “middle income” status – a key component of the country’s “2020 vision” to modernize.