Biodiesel - fuel for thought
Paul Martin is an advocate of biodiesel and a member of the Melbourne Biodiesel Club. He kick started the discussion by briefly explaining how a diesel engine works, as opposed to a petrol engine.
“It’s a compression injection engine, as opposed to a spark engine,” he explains. “And if you put the right fuel in, then it’ll last a long time. Diesel engines are very refined these days. You can run fossil oils, animal fats, vegetable oils, or alcohols; the idea was that you could use what ever was available locally to you.”
At this point, it is necessary to point out the biofuels are broken down into two main categories – ethanol and biodiesel. Less than three per cent of vehicles in Australia are reported to have diesel engines.
One litre of biodiesel will take you a similar distance as the equivalent amount of fossil fuel, depending on whether you use animal fat or vegetable oil. Once converted to biodiesel, vegetable oil has a little less energy, whereas animal fat has a little more energy.
“To make it properly, you set up a little plant, which’ll cost you between $500 and $1000, depending on how much fuel you are going to make, and then it’s not very difficult,” Paul continues, saying that there three major steps to go through. Cleaning the oil, the removing the glycerine, neutralising it.
“You actually have to chemically modify the fat or oil. You use an alcohol, usually methanol, and a catalyst, which is the same ingredients you use in soap. It’s a process that’s been done over a hundred years, removing glycerine from vegetable oil and animal fats.
Then suddenly one day, they decided that this by-product we’re getting from glycerine production, could run a diesel engine. And hey, now the glycerine is a by-product.”
Robbie called in. He has worked in the biofuel industry and according to him; to be dealing with the waste stream is the biggest issue facing the whole bio-diesel industry. He says that there is a worldwide glut of glycerine, so getting rid of it, in a commercial sense, is quite difficult at a low price. So the biggest challenge that sits in front of this whole industry appears to be, what do we do with the waste stream?
Bob rang, and he reckons he tosses it on to the compost heap because the by-products are biodegradable. It does come from a vegetable source. “If it is bio in the first place, I guess you can put it on the compost, and grow stuff, grow more diesel. Why not?”
The exhaust from bio-diesel, if it’s properly processed, is probably fine. But if it’s imperfectly manufactured, then it might not be so fine at all.
Back to Robbie, making the observation that the exhaust from bio-diesel, if it’s properly processed, is probably fine. But if it’s imperfectly manufactured, then it might not be so fine at all.
So you don’t want to be messing around making half-baked biodiesel, because you’ll make more of a mess than we had in the first place. “That seems to be a bit of an anomaly,” he says, “because you’ve got people saying ‘I want to save the planet, I want to use fish and chip oil’, but then, maybe they’ve got no consideration of what comes out of the exhaust of their car.”
Robbie’s last point is in regard to excise. The making of fuel requires an excise licence from the Australian Tax Office. If you do make biodiesel to standard, you can become eligible for a grant, which in fact returns that amount to you.
“You have a choice,” says Paul. “You can live with fossil fuel, accepting the pollution and what happens in that industry, or you can make it yourself, and decide to be responsible for your own emissions.”
Paul is currently helping people who are looking at growing Canola and using some of that crop to run the farm machinery. It’s probably a good step that oils and fats are not just being thrown away, but are utilised in some positive way, but that doesn’t make biodiesel the answer to all the worlds’ energy problems.
“Yes, we all agree, it’s a marvellous idea, but if you’re going to do it in your backyard,” concludes Red, “it’s a bit like making moonshine. Yeah, you’ll feel good for a while, but then, if you’re not careful, you’ll poison grandpa and he’ll never walk again.”