PetroSA Biogas Project
In October 2007, BioTherm commissioned its 4.2 MW Biogas Project at the State Owned PetroSA refinery in Mosselbay in the Western Cape Province. This project was the first non-recourse project financed IPP deal to be concluded in South Africa. This project was also the first project to successfully register for Carbon Credits (“CER’s), and is also the first project to monetise CER’s in South Africa. The biogas-to-electricity project was registered with the international CDM board on September 29, 2006, and took 11 months to construct.
PetroSA operates the Gas-to-Liquids (GTL) refinery at Duinzicht, about 12 km from Mossel Bay. The production process at the PetroSA GTL refinery leads to waste process water that is treated and returned back to the GTL process by passing it through Anaerobic Digesters. The anaerobic digestion is continuous process, critical for the successful operation of the PetroSA plant and produces a Methane rich biogas as a by-product. Prior to the MethCap plant being put into commercial operation, the biogas was flared to achieve full methane destruction. It is estimated that the equivalent of at least 1 300GWh of gross heat value has been wasted in this manner over the lifetime of the plant.
The MethCap plant use this waste biogas to generate electricity that is used on-site by PetroSA making the refinery less reliant on electricity supplied from the national grid. The biogas is piped to three GE Jenbacher reciprocating gas engine generator sets, each with a capability to generate a maximum of 1412kW at full load. The environmental benefits of the project will be less greenhouse-gas emissions by the national grid, and the more efficient use of energy and resources in the country. The MethCap plant is operated and maintained by BioTherm Operations and Maintenance, a subsidiary of BioTherm Energy.