IN May Rwanda formally opened a unique $200 million methane power plant Monday with hopes that it will one day provide 60% of the country’s electricity.
The generation station on Lake Kivu, known as KivuWatt, close to the country’s border with the Democratic Republic of Congo, is the only gas water extraction power plant operating in the world.
That is a happy record to have in the pocket, but the more significant thing is that it is a *hack that will also help reduce the risk of a potentially catastrophic natural disaster should the lake’s vast quantities of methane and carbon dioxide be disturbed by an earthquake.
Beneath the lake is water saturated with methane, carbon dioxide and hydrogen sulfide gas. If released, energy experts fear, “this toxic combination could take the lives of the more than two million people that live along the lake’s shores.”
Their fears are not unfounded. Cameroon witnessed one of its worst natural disasters in 1986 when a cloud of carbon dioxide detonated from Lake Nyos in a 100-metre fountain, killing almost 2,000 people as far as 25 kilometers from shore. One of the most densely populated countries, and the eighth smallest in Africa, the danger to Rwanda of a Lake Nyos-type explosion was much greater.
While mitigating a potentially monumental disaster, Rwanda also took another step to fix its power deficit, in a country with few energy options save importing diesel fuel. The lake has a methane potential estimated at 60 billion cubic metres, which it tamed and harnessed in one of Africa’s postcard-worthy acts of scientific and innovative flair.
“Many came and concluded that this thing could not be done,” Joseph C. Brandt, C.E.O. of Contour Global, the U.S. energy company that pulled off the feat said, adding, “We tried, and when we failed, we kept trying. Eventually possibility became probability and then certainty.”
The KivuWatt switch was first turned on December 31, 2015, producing energy in excess of the planned 25 megawatts from day one. It now aims to scale up to 100 megawatts, nearly doubling the country’s energy capacity, by 2020.
“KivuWatt’s 3000-ton extraction barge, moored 13 km from Lake Kivu’s shoreline, draws the gas-laden waters from a depth of 350 meters. As the waters come closer to the surface, where there is less pressure, the gas bubbles out, much like what happens when a champagne bottle is uncorked,” Time reported, adding.
“The gas is siphoned off for cleaning while the degassed water is injected back into the lake to maintain the ecosystem. Finally, the purified gas is piped back to the mainland where it fuels generators that supply electricity to the national grid. In a developed country, the current 25 megawatts would provide enough energy for 45,000 people. In largely rural Rwanda, it is already enough to radically transform livelihoods.”
An April 2015 article in MIT Technology Review called it a “great gamble”, capturing well the popular misgivings with which the project was viewed for many years.
- A hack: a clever solution to a tricky problem.