In the next step, it is envisaged that 20 further buses might be commissioned in Johannesburg.
Other municipalities in South Africa are likely to start adopting this technology soon as well – because it supports local employment and production, and is no less cost-effective than diesel (which is derived from imported oil).
The same could be done in many other African countries – both for public transport and for commercial trucks.
All of the ethanol being supplied for the envisaged ethanol-powered buses in South Africa is likely to come from Silversands Ethanol, which is based in Lichtenburg, North West Province.
There, farmer Derek Mathews has an ethanol distillery – one of the few biofuels projects which has actually eventuated from the many megawatts of hot air generated about biofuels in South Africa.
Mathews has also developed an ethanol gel stove and other products to use the ethanol he produces.
Mathews initially used maize as a feedstock, but has since switched to Syngenta tropical beet – another first in South Africa.
Mathews’ distillery has capacity to produce 1m litres per year, which is small compared to the large sugar company ethanol distilleries in sugar producing areas of South Africa and Swaziland.
But the Scania bus development holds the prospect of a vastly-increased demand scenario for Silversands Ethanol – and possibly others which emulate it – in future. It is envisaged that local distilleries would be built close to municipalities and other places where there is demand for ethanol fuel. Large central distilleries would not be needed. This model has been applied in a number of other countries.
Considerable work had to be done by Mathews into meeting the specifications required for the Scania vehicles, but he now says that this is a challenge that has been overcome. In future, when setting up distilleries, they could use any type of raw material (not just beet) – for instance, waste materials which would otherwise normally go into animal feed.
The technology driving the Scania buses is mature – it has been applied in Sweden for over 20 years. In Stockholm, over 700 buses have operated on the ethanol engines.
Scania only began exporting the technology about three years ago, and its ethanol engines now power buses in Madrid (Spain), La Spezia (Italy), Slupsk (Poland), and Australia.
The engine is environmentally-friendly, meeting the European EEV vehicle standard.
The buses run on pure ethanol, with a 5-7% additive that improves ignition and lubrication. The fuel is not a blend of ethanol and petrol, as is used in many cars in Brazil (and some other countries).
Mathews says that the Scania technology will revolutionise the ethanol fuel market, making ethanol fuel cheaper and easier to produce. This is because the ethanol used in the engines is hydrolysed and does not need to be “dried”.
The ethanol engine is an adaptation (in its third generation) of Scania’s 9-litre diesel engine with charge-cooling and exhaust gas recirculation (EGR).
According to Scania in South Africa, the ethanol is of a special quality (94% pure, against most ethanols which are around 70%).
The SA bus’s 9-litre engine runs at about 1.8km/litre, compared to diesel buses at 2.2km/litre. But there is an adjustment in the ethanol price for this lower power output. The ethanol, being locally-produced, could have a price advantage in the longer term, subject to negotiation. The total cost of manufacturing the Scania buses is 5-6% higher than equivalent diesel buses.
Trucks can also use the engines; smaller-than-9-litre engines are not contemplated.
In the current situation in which ethanol is not readily available everywhere (as petrol and diesel are) in African countries, ethanol buses and trucks ideally need to have a limited range in which they operate, and return to at the end of the day. Later this might change.
The development is significant for the rest of Africa because much of the gross domestic products of non-oil-producing African countries are consumed by payments for oil imports for the transport and other sectors.
Mathews: Tel 27 861-007-286;firstname.lastname@example.org