Posts in fuel
The Effect of Travelling Speed (Aerodynamic Drag) on Fuel Consumption

Air is thick stuff. Even a 10km/h headwind can play havoc with fuel consumption. Here’s why:

At 100km/h, aerodynamic drag accounts for about half the total resistance acting against the car’s forward progress. Battling into a 10km/h headwind is like driving into still air at 110km/h. But unfortunately the drag doesn’t go up by just 10 per cent. It’s more like 20 per cent, because drag varies with the square of speed. Twenty per cent of half the total resistance means 10 per cent higher fuel consumption.

(The maths:

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tech, fuelJohn CadoganComment
Ethanol: What, When, How...Huh?

This is the background briefing on ethanol in Australia as an automotive fuel

WHAT IS IT?

Ethanol, a.k.a. ethyl alcohol, pure alcohol, grain alcohol or drinking alcohol, is the second most common alcohol – a clear, colourless, volatile liquid. It’s the same stuff as in beer, wine and spirits, although the not-for-human-consumption stuff is ‘denatured’ by adding ‘bittering’ agents like denatorium benzoate and/or toxic chemicals like methanol and naptha – making it unpalatable and/or deadly.

CHEMISTRY 101

Ethanol is two carbon atoms, six hydrogens and an oxygen, all joined at the hip. It’s most commonly produced by fermentation of molasses, waste wheat starch or sorghum – where yeast eats sugary compounds in a balmy climate, excreting ethanol and CO2. Ethanol kills the yeast when the concentration gets to 15 per cent – not coincidentally the upper limit for beer and wine. Beyond that, you need to

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fuelJohn CadoganComment
Ethanol V Petrol: there's no clear winner

There’s been a lot of controversy, but ethanol in petrol is here to stay. Holden will have E85-compatible engines here very soon in an attempt to get fuel companies to supply even higher ethanol blends than are currently available. Amid all the anti-ethanol hysteria and fuel-company hype, not very much has ever really been explained about the key differences between the two fuels.

NOT FOR EVERY CAR

Most cars can run E10 – a 10 per cent blend of ethanol in petrol. To check compatibility with your car, contact the manufacturer. Ethanol doesn’t destroy engines, but it can eat into the materials used in incompatible fuel systems (sealers and linings; that kind of thing) and the byproducts of that corrosion can block fuel injectors, which can be costly.

WHAT’S ETHANOL?

It’s a basic alcohol, the same stuff as in beer, wine and spirits. It can be made by fermentation of a variety of different energy-dense foods. In Australia, the majority of ethanol is produced from

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Oil Price Vs Petrol Price

Why oil price movements are very different to petrol price movements

OPEC: Not so happy when oil prices fallThe alarm bells started ringing for Abdalla Salem El-Badri in about August 2008. Oil prices had started freefalling by then. The OPEC Secretary General hastily convened crisis meetings in September and October, during which the cartel – which controls 40 per cent of global crude oil – agreed to slash production by a total of two million barrels per day. That’s about 318 million litres daily – a box 100 metres by 100 metres at the base, stretching 32 metres into the air.

It was the eve of the global financial crisis. With the US and other notable economies casting about for the Last Rites, demand for petroleum products had fizzled. Economies run on petrol, basically. A barrel of crude hit its stride just before

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fuelJohn CadoganComment