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Lake Kivu lies on the border between the Democratic Republic of the Congo and Rwanda. It’s almost the size of Mauritius and has a maximum depth of 480 metres. For decades, Lake Kivu, with its high concentration of methane and carbon dioxide, was seen as a risk due to its potential for toxic release. This Lake has been known as the “killer lake” due to huge amounts of biogas trapped under a layer of heavy water containing minerals washed out of the nearby volcanoes. The carbon dioxide originates from two active volcanoes at the lake’s northern side: the Nyiragongo and the Nyamuragira. These 20,000 year-old volcanoes are among the most active in the world. The methane comes from the degradation of organic matter produced at the lake’s surface and the second process which produces most of the methane in the lake is the conversion of carbon dioxide into methane. When the gas concentration gets too high, or the lake is hit by one of the regular earthquakes in the region, the gas can be released, posing a threat to the people living in the vicinity. This lake contains high concentrations of naturally occurring methane gas (CH4) and carbon dioxide (CO2), with the highest concentrations at depths ranging from 270m to 500m at an area of around 2400km2. Lake Kivu’s bottom most waters absorb high concentrations of carbon dioxide (CO2) from magma-heated springs deep underground, and microbes convert much of the CO2 to methane. These dissolved gases are held in solution by pressures in the depths of the lake: Studies suggest that as much as 250 to 300 cubic kilometers of CO2 and 50 to 55 cubic km of methane is trapped in the lake’s deep waters. However, the gases can emerge if zones of high concentration move toward the surface, a process known as a limnic eruption, or “overturn.” Because the region is regularly subject to large-magnitude seismic events and volcanic discharges and considering that methane has a high partial pressure Lake Kivu is known to experience violent overturns. The concern is founded on the recent, sudden degassing from two much smaller volcanic lakes in Cameroon. In August 1984, a CO2 burst at Lake Monoun, thought to have been caused by a landslide, asphyxiated 37 people. In August 1986, a much more catastrophic event at Lake Nyos, a gas cloud that erupted in a giant water fountain of more than 80 m in height resulted in 1,746 casualties as well as the loss of more than 8,000 livestock, and prompted an international response, which included a conference organized by the United Nations Educational, Scientific, and Cultural Organization (UNESCO) in early 1987. Concerns about an overturn of Lake Kivu ramped up after January 2002, when the Nyiragongo volcano; one of the most active volcanoes on Earth sent a voluminous lava stream into the lake from the northern Congolese shore. That event fuelled concerns that an increase of dissolved gases (particularly methane) could prompt a limnic event within 80 to 200 years, posing a treacherous hazard to its riparian population of about 3.5 million. Studies have predicted that a saturation point will eventually be reached that could lead to a catastrophic gas release. Extraction of the gas has thus the potential to both mitigate the risks of dangerous eruptions and provide substantial energy reserves. The resource is equally shared between Rwanda and the Democratic Republic of Congo. Until 2004, extraction of the gas was done on a small scale, with the extracted gas being used to run boilers at a brewery in Gisenyi. Since then, the Government of Rwanda has prioritized the production of electricity from this unique resource in order to address the growing electrical energy deficit. In 2009, Rwanda signed a $325 million deal with ContourGlobal for a two-phase plan comprising integrated methane gas extraction and production facilities, and an associated power plant with capacities reaching 100 MW. The first $142 million phase of the project, “KivuWatt,” entailed a 750-ton barge that houses a gas extraction facility, and a 26-MW power plant comprising three 20-cylinder 34SG gas-powered engine sets supplied by Wärtsilä. The construction of an integrated methane gas extraction facility (25MW first phase) began in August 2011 and its operations began in December 2015. KivuWatt is the only one of its kind in the world. By tapping these gas resources, ContourGlobal is making Lake Kivu a safer place, while at the same time utilizing the trapped methane gas for much needed power generation. This will expand household access to power, lower costs, and reduce environmental hazards. The first phase of this project is powering three gensets to produce 26 MW of electricity for the local grid. It will reach 100 MW in the second phase; a phase which will deploy nine additional gensets at 75 MW, additional barges, gas extraction and treatment facilities as well as submerged pipelines to create a total capacity of over 100 MW. Methane gas is extracted through an auto-syphon process that is initiated when a pump draws gas-laden water from the lower resource zone of the lake (below 355 m) through large gas extraction riser pipes, until it reaches horizontally mounted gas separators, which are located 20 m beneath the platform. As the water is transported through the riser pipes, the gas in the water which is initially methane (CH4), then CO2 and hydrogen sulphide bubbles upward from depths of about 240 m. The “degassed” water is then re-injected into the lake, where it safely re-stratifies with the CO2-laden waters. The separated gas “sour gas” is then piped through a series of wash towers along with wash water, which is extracted from the lake surface (at a depth of about 40 m). The gas flows upward and the wash water downward through a series of trays in a process designed to dissolve the unwanted CO2 and hydrogen sulphide into the wash water. The result is a sweetened gas of about 90% CH4, with the remainder comprised of CO2 and nitrogen. The gas is then compressed, dried, and transported to the power plant through a pipeline and at the power plant, combustion engines generate electricity to be supplied to the Rwanda energy grid. Recently, Shema Power Lake Kivu Limited (SPLK ltd) signed as well a 25-year power purchase agreement (PPA) with the Rwanda Energy Group (REG) for a 56 MW net power output from methane gas. This company invested $400 million in this project known as Kivu56 and its production will be added to the national grid. The Power plant will be located on Nyamyumba sector in Rubavu District. The project, which started in October 2019, is set to be finalised by December 2022. Shema Power Lake Kivu (SPLK) is set to produce 15 megawatts of electricity in its first phase of methane gas extraction from Lake Kivu. The first phase is expected to address the challenges of electricity shortage in Rubavu District; a strategic area for Rwandan businesses eyeing the DR Congo market. This Kivu 56 Methane Gas to Power Plant (K56) will be the lake's second operational power plant. The Kivu-56 project is expected to positively impacting both the economy and local inhabitants, providing reliable, green electricity and safer lakeside existence. Many local residents are included in the construction of the gas extraction barge and power plant, resulting in earned income and new job skills. Also, local companies in agriculture and tourism will have consistent electricity to power their businesses, allowing for greater output and export potential. All these projects will mitigate the dangers associated with the release of CH₄ and CO₂ from the lake, as well as providing an environment-friendly and sustainable source of power generation. Furthermore, these projects will decrease the country’s use of diesel to generate electricity, reduce electricity costs and enable the country to address the growing energy deficit and achieve its target of providing access to power to all Rwandans by 2024. The Rwandan government plans to reach an electrification rate of 100% by 2024. The methane in Lake Kivu is estimated to have the capacity to generate 700 MW of electricity over a period of 55 years. Rwanda’s share of the total generation potential is about 350 MW, with the rest being shared with the Democratic Republic of Congo.