Technicians from UK turbine manufacturer Peter Brotherhood have recently completed commissioning the largest steam turbine ever installed in an African sugar mill.

The 20 MW turbo-alternator set was designed and manufactured by Peter Brotherhood for contractor PMS which is helping to refurbish the mill in Hippo Valley near Chirezdi, Zimbabwe, owned by Hippo Valley Estates.

The 50 tonne turbine was lowered into place within the mill through a hole created for the purpose in the roof of the power house, then installed and commissioned.

The back-pressure turbine will use steam raised from burning bagasse – the waste material left after the processing of sugar cane – to generate the mill’s electrical power, while the exhaust steam will be used in the sugar refining process. This is believed to be an extremely ‘green’ form of power generation because all the CO2 released during combustion of the bagasse is absorbed again the following year by the growing crop.

Peter Brotherhood has more than 500 steam turbines operating in sugar mills around the world, including more than 100 in Africa. The machine in Hippo Valley is almost 50 per cent bigger than any similar turbine known to be operating in Africa.