Agco Sisu Power has developed prototypes of a tractor engine that runs partly on bioethanol produced from sugar cane and partly on diesel. Under development at the Valtra tractor plant at Mogi das Cruzas, Brazil, it is dubbed the Dual Fuel project.
The two liquids are not mixed. Instead, there are separate diesel and ethanol injectors. The ultimate goal is to burn 70% ethanol and 30% diesel, but at the moment the two engines being tested in the field use a 50/50 mixture.
It will be a two-tank system, says the company, with the ethanol tanks located either side of the diesel tank.
|The new engine has two fuel lines – one for diesel and one for bioethanol. There will also be two fuel tanks.|
Biofuels are widely used in Brazil. Almost 90% of the country’s 9.4m cars burn ethanol or a petrol/ethanol mix. It is a huge industry that consumes almost half of the country’s 8m ha of sugar cane.
Some large sugar farms run fleets of 200 to 300 large tractors, and it is these that are driving demand for a bioethanol tractor engine. Valtra hopes to launch its first production engine some time next year and says it will cost 5-10% more than a standard tractor engine. Despite that extra cost, it reckons it will be making 3000 units a year by 2015.
Ultimately the plan is to make both smaller and more powerful engines. But for now, the focus is on the 180hp unit, the most popular engine size on Brazilian sugar farms today.
Before the engine goes on sale, Valtra engineers will have to look hard at the engine’s power delivery characteristics. At full power ethanol-powered engines can be prone to knocking. “It is a fine line to find the right balance of diesel and bio-ethanol,” says vice-president and managing director Eero Tomi of AGCO Sisu Power. “Our target is to develop an engine that offers the same performance and power as a diesel engine.”