Bioenergy The treasure of Lake In the energy-poor country of Rwanda only 10 % of households have an electricity connection. But scientists have now discovered a renewable energy source in the depths of : methane gas. Rwanda aims to soon be generating so much electricity from this that it will be able to export to neighbouring countries too.

atrick Muhizi turns the volume up on his stereo Lake Kivu is considered to be one of the most dan- system and hip-hop music spreads out ­across gerous lakes in the world. It lies on a fault zone, the Pthe completely flat surface of Lake Kivu. The 20- East African Rift. Inquisitive geophysicists and vulcan- year-old Rwandan is sitting in an open beach hut and is ologists can thus often be seen sitting in ­Muhizi’s entertaining his party guests. It is evening here in the beach bar. They are drawn to the 485 m deep lake by a small town of Gisenyi on Lake Kivu, which separates unique treasure, for in the layers at depths below 70 m Rwanda from East Kongo. Muhizi has put up coloured gases are dissolved under pressure, as in a bottle of chains of lights between the huts of his beach bar and fizzy water: an estimated 54 km3 of methane and steaks are sizzling on the grill – the bar is a popular 250 km3 of carbon dioxide. What makes the lake so party location. “But only as long as there is electricity,” dangerous is the so-called champagne effect, as re- he sighs and looks out across the lake with a worried searchers warn. The upper layers of water act like a expression on his face. There is a lit platform out there, cork; they provide enough pressure to keep the gases similar to an oil platform, and Muhizi knows: if the dissolved in the water. But if an earthquake, lava flows lights go out there, then the light chains will also be from the nearby volcanoes or high waves disturb the going out at the beach bar. upper layers, the pressure drops like when the cork of a shaken bottle of champagne is popped. Lake Nyos in Cameroon emitted a gas cloud in this way in 1986. As it is heavier than air, 1.7 million tons of CO2 rolled off the lake onto the shore. 1,746 people died within minutes. Lake Kivu has also emitted gas at the surface on occasion, which has suffocated swim- mers. These gas-bearing waters are thus known as kill- er lakes, but Lake Kivu is unique even among these. Only it contains the easily combustible greenhouse gas methane as well. Scientists warn of a looming catastro- phe in one of the most densely populated regions in the world. The governments of Rwanda and the Demo- cratic Republic of the Congo (DR Congo) have thus de- cided: the gas must be extracted. Thus our story moves on and chief engineer ­Alexis Kabuto is racing along the road on the shore in his off- road vehicle. Not far from Muhizi’s beach bar, he shows soldiers his passport and then drives on. In a bay, en- gineers are doing welding work on a further platform secured up against the shore: “The extraction platform is being overhauled,” he explains, and then points with his finger out onto the lake.

Like through a straw, the methane gas bubbles up from the depths of the lake and into this tower. The methane extraction plant is a Rwandan showcase project. The government aims to expand the plant to up to 50 MW with the help of foreign investments. Photos (4): Simone Schlindwein

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to it: “And here the carbon dioxide is scrubbed.” What remains is the methane, which is then pumped to shore and used to generate electricity”. More electricity than the country needs

Kibuye Power has a concession for a total of 50 MW. In order to be able to install this power, the platform must be expanded. An investment of US$ 200 million will be required, money which Rwanda doesn’t have available on its own. And yet the country desperately needs cheap electricity. A study says that only 10 % of households have an electricity connection. Most of the ­power is gen- A second platform is being overhauled at the shore of Lake Kivu. Its power is also erated using hydropower, but during the dry season riv- 3.6 MW and is to be expanded to 50 MW in the future too. The plant belongs to the er levels fall and the power stations cannot supply Rwanda Energy Company, a subsidiary of a Rwandan investment group. enough electricity. During these periods, diesel genera- tors clatter away all across Rwanda in order to keep of- Methane extraction as a fice buildings and industrial plants supplied. Rwandan showcase project But the transportation of diesel from the far-away port on Tanzania’s coast is expensive and not environ- There, a tower like an oil-drilling platform can be seen mentally friendly, stresses Coletha Ruhamya, ­Rwanda’s above the waves of the lake. A pipe floats on the sur- State Minister for Water and Energy. The young woman face and winds its way from the platform to the shore. is sitting in her office at the Ministry for Infrastructure in It is being used to pump the methane from the platform . In front of the ministry, the road is being freshly 1.8 km out on the lake to the generators rattling in a tarred and not far away Africa’s largest conference cen- building on the shore. tre – with a five-star hotel and a shopping centre – is be- Kabuto parks his vehicle in front of the hall, gets ing built. In order to supply all these new buildings, a lot out, and opens the door behind which the machines more cheap electricity will be required, explains Ru- are roaring. Kabuto is the manager of the company hamya. Kibuye Power, the state-owned business which runs The Ministry for Infrastructure is thus thinking about the plant. Three generators, each with 1.2 MW of alternative power supplies – biogas, geothermal and electrical power, generate electricity by burning the solar power plants are to be built. Of all of these resourc- me­thane. Kibuye Power then feeds this into the na- es, the methane gas currently seems to be the most This pipeline is used to pump tional grid. But with the generated output it is not yet promising. By 2020, says the minister, 35 % of house- the methane gas to generators pos­sible to light up every household in Gisenyi. holds should be hooked up to the grid and electricity on the shore. The generators There are outages at the beach bar almost every connections are also currently being laid to the neigh- come from Germany and can ­other evening because demand is either too great or bouring countries of DR Congo and Uganda. For as soon generate a total of 3.6 MW of because the methane plant is experiencing technical as the four currently planned methane projects at Kivu electricity. difficulties. have all been expanded to maximum capacity, Ruhamya And yet: the plant is a Rwandan showcase project. expects to be able to “export electricity to neighbouring The government has invested US$ 20 million so far and countries.” manager Kabuto is happy to show people around. Ivan Twagirashema is confident of being able to get Rwanda is looking for investors to build larger power together the approx. US$ 150 million for the construc- plants following on from the current pilot plants. In the tion of a 50 MW platform. The trained chemist is respon- long term, generators with a total of 700 MW could be sible for the second project on the shore, which is cur- kept running by the methane in Lake Kivu, say optimis- rently being overhauled: the platform belonging to the tic studies. The bordering countries Rwanda and Rwanda Energy Company (REC), a subsidiary of the DR Congo are to share this potential, with each country Rwanda Investment Group. “We are currently negotiat- installing 250 MW. The two neighbours want to get a ing with international investors who wish to be a part of joint project going to this end which will generate this exciting and unique project,” he says. Similar to the 200 MW of electricity, but the Congolese government is Kibuye Power extraction station, the REC plant is ­also to not yet ready to enter the planning stage. be expanded to 50 MW in stages. Right now, however, In Rwanda, on the other hand, Kabuto is already it must be overhauled to even run with the 3.6 MW al- enthusing about industrial manufacturing. As we step ready installed. Still, Twagirashema is certain that the into a rubber dinghy, he tells of his studies in Germany. biggest challenges already lie behind them: “We start- When we arrive at the modern operating room on the ed with a project idea which only existed as a theory on Three generators made by the methane platform, he points to the computer monitor paper.” He shows us photos from the other side of his German manufacturer Deutz displaying the platform in bright colours. In the middle desk, which show flares blazing away from a tower on generate electricity here by a bell is displayed: “The gas mix comes in here,” he the lake shore. “These methane flares are proof that we burning extracted methane shouts, trying to make himself heard above the clatter- are extracting gas from the lake,” he says and nods with gas. ing of the pumping station. Then he points to a box next his eyes shining brightly. Simone Schlindwein

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