Adelaide research fuels petrol alternatives

Automotive Engineering

With higher fuel prices here to stay, is biodiesel one of the answers to our reliance on petroleum-based fuels?

University of Adelaide researchers are investigating biodiesel's potential, not just for larger vehicles such as trucks which are the traditional users of diesel, but for engines in cars and even motorcycles.

Dr Colin Kestell and Dr Con Doolan oversee the new and extremely popular Automotive Engineering degree offered by the University's School of Mechanical Engineering, and will be working together with industry and Automotive Engineering undergraduate and postgraduate students to research and develop biodiesel as a viable and sustainable fuel.

They say biodiesel has many advantages compared with petroleum and even other mooted fuel alternatives.

"Biodiesel is a sustainable fuel which is already available and is being used around the world," Dr Kestell said.

"There are a number of councils and transport authorities around Australia that are using it, with garbage trucks, buses or road sweepers using either a mix of traditional diesel and biodiesel, or biodiesel alone.

"What we are looking to do is to use the research expertise available here at the University, and in conjunction with industry, look at developing smaller engine systems for cars or even smaller vehicles which can use biodiesel effectively and efficiently."

Diesel engines differ than from petrol engines because they compress air to high temperatures to ignite the fuel, rather than use spark plugs. As a result, diesel engines are more fuel efficient but rely on a heavier, less refined and less volatile fuel.

This has seen diesel engines used primarily in bigger vehicles with correspondingly bigger engines, such as buses, trucks and tractors. But recent developments in engine technology mean that smaller, clean, efficient and quiet diesels can be used in everyday cars.

"The 'bio' in biodiesel stems from the fact that it can be derived from almost any type of oil: oil-yielding plants, algae, or even waste fat and oil, such as discarded oil from fish and chip shops," Dr Doolan said.

"It is cheap to make and it is eco-friendly, because the source of the fuel absorbs carbon dioxide as it grows, rather than fossil fuels which are non-renewable.

"The main issue associated with biodiesel is the associated emissions of some pollutants. We hope to provide a better understanding of the biodiesel combustion process in internal combustion engines, and look at engine designs which maximise fuel efficiency and performance while also minimising emissions."

Dr Kestell said that in 2006 final-year Engineering students, as part of their course, will design and build a biodiesel motorbike to show how versatile the fuel is.

"It's only going to be a one-off prototype, but it still makes an important statement, that a biodiesel engine doesn't need to be big to be effective," Dr Kestell said. "You could have a canola farmer using a biodiesel motorbike to check on his crops, and to run it with the fuel which comes from the oil in the canola plants he's checking!

"A common criticism of biodiesel is that it will be impossible to produce sufficient quantities for current or predicted fuel demands. We think biodiesel isn't the definitive alternative fuel that will replace all others - rather, it's just one part of an overall solution which involves hydrogen fuel cells and other biofuels such as ethanol.

"In Germany, biodiesel already accounts for 10% of its transport diesel consumption and if that figure is applied worldwide, then it's quite significant."

Story by Ben Osborne