The road approaching Bronkhorstspruit’s Bio2Watt’s plant is lined with dozens of beef cattle farms on both sides. Around 25 000 cows roam freely in large enclosed fields. But what is of interest to the large building next door is neither their meat, nor their milk: it is their manure and the carcasses provided by nearby abattoirs. Why? Because Bio2Watt’s plant in Bronkhorstspruit needs vegetable and animal waste – such as cow manure – to produce biogas, a renewable, green energy source.
“We choose this site because of its proximity to a large commercial feed lot”, says Sean Thomas, managing director of Bio2Watt, the largest biogas plant in Africa. “Besides being the main raw material for energy production, cow manure also feeds our four digesters to produce biogas”. The digesters essentially replicate anaerobic digestion – the natural breakdown of organic materials – by transforming the organic matter in waste into biogas. This gas, which has no negative impact on the environment, is then used to produce heat, electricity or as biofuel.
Thomas, who has been working in the field of renewable energy for over a decade, saw an opportunity for a biogas plant in South Africa. However, financing for renewable energy projects was – and still is – hard to come by: “The capital investment required for renewable energy projects is quite extensive. But biogas is a proven technology and there are many plants operating all over the world, so I felt that it was a technology that could be viable in South Africa, given the availability of waste here”, says Thomas.
And waste is indeed key, as biogas is produced by using a combination of cow manure as well as vegetable and animal waste. “Using waste from food processing factories has an added benefit to the environment, as this is food that would normally end up in landfills or waste treatment plants”, says Thomas.
Standing several metres high, the biogas plant’s four digesters operate 24-7, generating 4.4 MW of electricity that is 100% clean energy. An on-site electricity substation belonging to the national energy provider ESKOM and a 13 km distribution network allow electricity to be transmitted to the national grid.
This energy is then off-taken by BMW’s car manufacturing plant in Rosslyn, Pretoria, about 40 km from the plant. Thomas highlights that this green energy makes up one third of BMW Rosslyn’s power requirements and is in line with the BMW Group’s vision of becoming a leader in the use of renewable energy by 2020.
The environmental benefits of this waste-to-energy project are impressive. “By diverting approximately 40 000 tons of cow manure per year, we reduce CO2 and methane emissions, which are responsible for global warming”, says Simon Harris, plant manager at the Bronkhorstspruit biogas plant.
The plant also generates revenue through the sale of solid and liquid fertilizer, which is a by-product of the digesting process. “Solid fertilizer is our “solid gold” due to its high resale value. It’s used for fertilizing grass and for landscaping, while liquid fertilizer is used by farmers, especially during the hot and dry winter months”, adds Harris.
In addition to its environmental benefits, Bio2Watt’s Bronkhorstspruit plant has created over 50 direct and indirect temporary jobs and about 100 temporary jobs (like that of Thabo Broom, assistant manager and feedstock scientist, pictured in the photo above). International experts like Irish-born Simon Harris were brought onboard to train and improve the skills of the locally employed-workforce. “The project has created jobs and empowered the local workers in an area considered peri-urban and where job opportunities are scarce”, highlights Harris.
Bio2Watt is leading the way for future biogas waste-to-energy developments in South Africa and the rest of the African continent. The company is looking at expanding the capacity of the Bronkhorstspruit plant from 4.4 MW to 6.9 MW in the near future, and setting up similar renewable energy projects in other countries in Africa.
AFD’s green finance label Sunref facilitates access to low-cost renewable energy and supports sustainable use of natural resources. Sunref’s ultimate objective is to promote the development of a low-carbon economy and help fight climate change.
Through this programme, AFD supports financial institutions and their clients on their projects aimed at the sustainable management of natural resources and make us of clean energy. SUNREF’s innovation is based on the combination of a financial and technical approach: providing tailor-made financial instruments at the same time as building the capacity of banks and their clients to implement green energy projects.
Sunref, which stands for Sustainable Use of Natural Resources and Energy Finance, has already implemented 42 projects that support financial institutions towards adopting a more sustainable model of development. These projects make up 20% of AFD’s investments in the energy sector between 2012 and 2015, and 15% of its investments in the climate sector in 2016.