Faced with mounting environmental concerns, defunct coal mining operations and fluctuating energy commodity prices, many African countries, in response to global commitments for a green transition, have sought to incorporate increasing proportions of renewable energy sources to diversify their respective energy mixes. Offering potential solutions for increasing electrification and significantly reducing carbon emissions, underground coal gasification (UCG), is an emerging, clean coal technology that has a definitive role to play in Africa’s energy future.
As opposed to conventional surface gasification projects, whereby gasification occurs within a manufactured reactor, UCG is gasified in-situ – wherein the natural geological formation converts coal to synthetic gas (syngas) – through a partial combustion process via the injection of oxygen into the coal seam and then transported to the surface through a production borehole. Clean syngas is used for the synthesis of transportation fuels, electricity generation, and hydrogen production, offering considerable environmental benefits.
Majuba Underground Coal Gasification Project, South Africa
Serving as Africa’s first UCG plant, the Majuba UCG Project, in South Africa’s Mpumalanga province, produces high-quality syngas – a fuel gas mixture of hydrogen, carbon monoxide, and carbon dioxide – used for power generation at the 4.2 GW Majuba Coal-Fired Power Plant. Developed by the national utility, Eskom, using technology from Ergo Exergy, a UCG technology company, the project is unprecedented in its scale, complexity, and pioneering nature, utilizing coal deemed un-mineable due to frequent dolerite intrusions.
Theunissen Underground Coal Gasification Project, South Africa
Involving the gasification of approximately 5 million tons of coal across an area of 150 hectares and over the course of 20 years, the Theunissen UCG project, is expected to provide 50 MW of baseload electricity to the national grid upon commencement of operations. Located in South Africa’s Free State province, the project is being developed by technology company, African Carbon Energy through its principal subsidiary, Africary Holdings, targeting a coal resource of approximately 1 billion tons.
Serowe Coal Bed Methane Project, Botswana
Located in the Kalahari Basin in Botswana, the Serowe Coal Bed Methane Project is a coal seam gas reservoir, covering an area of approximately 4,750km2, comprising three licenses, the PL356/2018, PL016/2018, and PL400/2018 prospects. Having submitted the final environmental impact assessment in 2019, six wells will be drilled as part of an appraisal drilling campaign by Australian oil and gas exploration company, BotsGas, having signed a farm-in deal with exploration company, Strata-X Energy, which underwent a corporate merger to form Pure Energy.
Sterkfontein Coal Project, South Africa
Strategically situated in an area with indicated coal resources totaling 90.93 million tons, close to a high-tension powerline connecting the Tutuka power station in the Mpumalanga Province to South Africa’s national grid, the Sterkfontein Coal Project is a proposed coal mine located 143km south-east of Johannesburg that will target prospects from the Highveld Coalfield. Five coal seams drilled at the coalfield indicated the financial viability of the prospect, with UCG being considered to deliver syngas as a feedstock to the power station, while also serving to increase the coal resources.
Letlhakeng Underground Coal Gasification Project, Botswana
With significant portions of its coal resources situated over 200 meters in depth from the surface, gasification and coal pyrolysis offers a promising export option to harness the full potential of Botswana’s vast coal resources. Vastly underutilized, most of the southern African country’s coal deposits are contained in the Central Kalahari Karoo Basin and are mainly used for electricity generation at the Morupule Coal Mine. With a license to explore 1,000km2 for 500 million tons of coal resources, the Letlhakeng UCG Project is currently being fast-tracked by coal mining and energy development company, Shumba Energy, to improve the utilization of Botswana’s coal and find alternative methods of extracting higher value.