Scania Providing Buses for Ethanol Field Trials
22 May 2006
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| Scania ethanol-powered OmniCity bus. |
Scania, the world’s only manufacturer of ethanol-powered commercial vehicles, is supplying the city buses for use in the BEST consortium’s field trials of ethanol as a vehicle fuel. Scania heavy-duty ethanol engines use 95% ethanol with 5% ignition improver in a diesel engine.
The aim of the BEST consortium (BioEthanol for Sustainable Transport) (earlier post) is to support large-scale use of ethanol as a viable alternative fuel for both cars and commercial vehicles.
Among other things, it encompasses the building of ethanol refuelling stations and the launch of trials involving both cars and city buses in ten locations throughout the world. The initial trials will take place in La Spezia, a coastal city in north-western Italy. In addition to La Spezia, Stockholm, Rotterdam, Dublin, Madrid, Basque Provinces (Spain), Nanyang (China) and São Paulo (Brazil) are taking part.
The BEST project was started up by representatives of the Stockholm Public Transport Company (SL) and is partly financed by the EU.
Ethanol is an excellent renewable fuel for heavy commercial vehicles in urban operation. We regard this project as an important first step towards sustainable urban transport with renewable fuels. The environmental potential is great and Scania is using a proven technology that is fully up to the demands of tough urban operation.
—Bengt Rasmusen, Managing Director of Scania Bus Italy
The public transport company in La Spezia, ATC, has 250 buses in its fleet and transports around 18 million passengers per year. ATC will start operating three Scania OmniLink ethanol buses in its city bus fleet in September.
Scania has been supplying ethanol buses to public transport companies in Sweden for 15 years and has about 600 ethanol-powered buses in service.
To use the E95 blend in the diesel engine, Scania raised the compression ratio from 18:1 to 28:1, added larger fuel injection nozzles, and altered the injection timing. Different gaskets and filters are required, as well as larger fuel tanks—the engines use 65% to 70% more ethanol than they would diesel. (Earlier post.)
The intervals between oil changes is halved, and more scheduled maintenance is required.
The current ethanol engine generation introduced in 1996 reaches Euro 4 levels, which will be required from October this year. Around 600 ethanol buses have been delivered so far. Scania is now developing its next-generation ethanol engine, planned to be ready for introduction in late 2007.
Wouldn't biodiesel be cheaper/easier? At only a 7% increase in fuel consumption?
Posted by: JN2 | 22 May 2006 at 09:02 AM
"the engines use 65% to 70% more ethanol than they would diesel. (Earlier post.) "
which puts fuel consumption at what? 2 miles per gallon.
What city could afford to fuel these things in the long run?
Posted by: coal_burner | 22 May 2006 at 09:11 AM
The City of Stockholm does not seem to have any trouble affording it. They have been in service for several years now as the article states (i took a ride on an OmniCity ethanol bus just yesterday).
I'm a little curious why efficiency is so bad though. Wouldn't the extremely high compression ratio result in a very high thermodynamic efficiency? Where does all the energy go?
As for biodiesel, it is my understanding that Scania's ethanol diesel offer significantly lower emissions (NOx and PM, the latter is very important in the city).
The upcoming hybrid bus is also very interesting. It differs from other hybrids on the market by being serial (no transmission) and battery-less (using supercapacitors only).
Posted by: Fredrik | 22 May 2006 at 12:13 PM
Perhaps ethanol was chosen because its emissions are cleaner than biodiesels.
Posted by: tom deplume | 24 May 2006 at 06:00 PM
Since diesel is about 130,000 BTU per gallon and ethanol is about 80,000 BTU per gallon, I would say they do pretty well.
Posted by: SJC | 24 May 2006 at 10:46 PM