Electricity and Control July 2025

Measurement + instrumentation

The instrumentation solution for a uniquely challenging environment This application case illustrates the capabilities of VEGA’s instrumentation. Leon van Niekerk, VEGA Sales Engineer, says, “Put to work in the Lake Kivu methane extraction project, VEGA’s sensors demonstrate the role that advanced technology can play in addressing engineering challenges, providing accurate measurements for safe and e icient resource development.” L ake Kivu, which lies on the border between the Democratic Republic of Congo and Rwanda, presents a fascinating case study in limnology and geochemistry.

Leon van Niekerk, VEGA Sales Engineer.

the gases erupt to the surface, su›ocating life in the surrounding area. However, the benefits in this case outweigh the risks: the methane reserves represent a substantial energy resource. The process of gas extraction and use needs to be carefully managed to minimise environmental impacts on the lake ecosystem. Resource exploration and extraction Methane exploration in Lake Kivu has focused mainly on analysis of the gas composition, determining the composition of the gas mixture, including methane, carbon dioxide, and other potential components, and estimation of the quantity of gas by assessing the total volume of methane available in the lake’s depths. During the gas extraction process at Lake Kivu, various challenges presented themselves. Given the depth at which methane is concentrated, specialised equipment and techniques have to be used. Once extracted, the gas mixture is separated into its components, primarily methane and carbon dioxide. Mitigating the environmental impact of this process has to be considered, and careful planning is essential to minimise the impact of extraction on the lake’s ecosystem and surrounding communities. KivuWatt is a notable example of a successful methane extraction and power generation project on Lake Kivu. It has demonstrated the feasibility of harnessing this unique resource and served to highlight the complexities involved. The extracted and processed methane is

Its unique characteristics arise primarily from its location within the East African RiŽ Valley, a tectonically active region subject to volcanic activity and high heat flow. The nearby Nyiragongo and Nyamuragira volcanoes contribute significantly to the lake’s geochemical composition as the volcanoes release large amounts of carbon dioxide (CO 2 ), a key precursor to methane formation. The RiŽ Valley environment has led to the formation of a deep lake basin with a stratified water column. This stratification results in the accumulation of gases at depth. Organic matter from the lake’s ecosystem, including plankton and other organisms, sinks to the bottom, where it decomposes anaerobically. Without oxygen, communities of certain microbes convert the organic matter into methane (CH 4 ) as a byproduct of their metabolism. Due to its low solubility in water, methane accumulates in the lake’s deeper, colder layers, forming a gas rich hypolimnion. The dissolved CO 2 from volcanic sources also contributes to the accumulation of gas, creating a potentially explosive mixture. The high concentration of dissolved gases in Lake Kivu poses a significant risk of a limnic eruption, a rare but deadly event where

In the Lake Kivu project, VEGA instrumentation provides accurate measurements for the safe and efficient extraction of methane.

18 Electricity + Control JULY 2025