World: Biofuel - ethanol in petrol

First of two overnight BBC reports spoke to something I was doing yesterday.

They were talking about biofuels: fuel made from organic products such as ethanol from sugar cane (as opposed to petrol distilled through thousands of centuries of geological pressure). The consensus view was that at at a maximum 10% mix with normal petrol, it was no problem. In fact, the expert said, biofuels are less harmful for global warming.

Yesterday, prior to hearing this report, I tried to find out for myself the effect of an ethanol mix in petrol, since I’ve noticed more petrol stations in recent times have been offering an ethanol mix, in addition to the normal unleaded petrol (with bland irony, they tend to call this mix “unleaded plus”, whereas you’re actually getting less petrol with each litre).

Specifically, I wanted to find out:
a) Is it bad for my car?
b) What effect does it have on performance?
c) What is the nett effect on greenhouse gas emissions?

In Australia in recent times, there had been some furore over additives to petrol, particularly ethanol*. More recently, the federal government had legislated a 10% cap on ethanol in petrol, and required consumers be informed of that mix.

The answers? I rang the car manufacturer, and was told mine was fine for ethanol – at a maximum 10% mix. However, they were at a loss on the question of performance, and said I was the first one to ever ask about that!

An internet search verified that at that mix, there was no performance loss; however, the literature I read suggested that on a whole of lifecycle basis, the effect of the mix on greenhouse gas emissions was neutral (see here). The Wikipedia article on Ethanol fuel suggests similar (in referring to 100% ethanol). Perhaps the BBC expert hadn’t looked at ‘whole of lifecycle’; perhaps the difference is small enough to be negligible.

It’s worth looking at that Wikipedia article – Brazil and Columbia are being particularly innovative on biofuel.



*Part of the problem was the chief beneficiary was a company called Manildra, who had a virtual monopoly on ethanol distribution in Australia, and who was a major donor to PM John Howard’s Liberal Party, in return gaining great benefit from some Howard policy changes.