Lake Kivu in Rwanda is one of the world’s deepest lakes. However, the lake has high levels of trapped carbon dioxide and methane amounting to 300 and 60 billion cubic meters, respectively. Carbon dioxide in the water is released from molten rock material and fossil planktons, while they form methane from CO2 by bacteria. They hide these gases at a depth of 80metres from the river bed. Because of these poisonous energy gases, the government has come up with the Kivu watt project to help reduce their concentration levels in the lake. This project integrates the extraction of methane gas from the water body and uses it in power production.
Scientists have predicted that in case of a powerful earthquake, storm or lava flow into the lake, about 20 million people living around the shore have a probability of dying. This is because such magma and lava flow will cause an outburst in the lake. The water level will rise. Hence the toxic gases will escape and cause gas poisoning. In case of such havocs. Some aquatic animals e.g., fish, were also found dead on the shore sometime back. Though useful, the lake can cause irreversible damages to the people and the environment at large.
How is the gas extracted?
Following the integrated means, methane gas is collected. They conduct this process with the help of submerged pipes. They direct these pipes close to the lake bed where methane gas is generated. The pipes pump the contaminated water up the gas laden to the barge. Methane gas is siphoned and channeled to the power plant. The 25MW engines in the plant then generate electricity from the gas. The degassed water is returned to the lake.
Benefits of the project to the country
Kivu watt project contributes to about 30% of the country’s economy. It is a mitigation measure to the toxic gases present in the lake. Through siphoning out of methane and CO2, there is a reduction in concentration levels of the gases. Hence, the lesser danger is posed to the inhabitants around the shore together with aquatic life. Because of the project, about 51% of the Rwandans have electricity. The project has promoted universal electrification; both rural and urban inhabitants can access power. Power comes in handy with the growth of infrastructures. Following implementing the project, people gained employment opportunities. Some have permanent jobs while other contracts.
Most of all, with the project, there has been limited use of diesel to generate power. Especially as diesel fluctuates in price, the government of Rwanda is certain it will provide affordable electricity for its citizens. The energy will be available to everyone for an extended period. The estimated cost of completion of the project is a considerable sum. Its first phase is complete, and they are looking forward to finishing the second one.