Currently reading: New E10 fuel could reduce a car's economy by 10 per cent
A real-world study by What Car? suggests the government's plans to introduce new fuel could hit motorists in the pocket

The introduction of new E10 fuel could increase motorists' fuel consumption by more than 10 per cent. The new fuel, which contains 10 per cent bioethanol, will be rolled out across the UK as part of the government’s commitment to reducing emissions.

But real-world testing by What Car? magazine found that vehicles running on E10 are less efficient than the current E5 (up to five per cent bioethanol) blend of fuel across every engine type tested. This means cars have to use more of the new fuel, costing drivers much more each year.

What Car? tested E10 against pure unleaded using a Dacia Sandero, Hyundai i30, Toyota Prius+++ and a Mini Paceman. The Sandero registered a 11.5 per cent drop in economy, while the i30’s consumption increased by 9.8 per cent.

CO2 emissions also increased, although the Low Carbon Vehicle Partnership told What Car? that increases would be partially offset by the renewable properties of bioethanol.

The Society of Motor Manufacturers and Traders said that only 92 per cent of UK cars will run on E10, leaving 1.5 million petrol-powered vehicles at risk of not being able to use the fuel.

According to What Car?, the fuel had previously only been tested in laboratory conditions and the potential impact on fuel economy and CO2 emissions had not been communicated to motorists.

The fuel is expected to be introduced to the UK market later this year as part of the government’s commitment to reducing greenhouse gas emissions and conforming to the EU’s Renewable Energy Directive. This requires 10 per cent of road transport energy to be from renewable sources by 2020.

What Car? editor-in-chief, Chas Hallett, called on the government to carry out in-depth tests to understand the financial impact on drivers. He said: “The US Environmental Protection Agency estimates that the detrimental effect of E10 on fuel economy is between three and four per cent, but even our small sample of tests proves otherwise.

“To lead consumers into E10 without fully communicating the significant impact on fuel economy, particularly for drivers least able to absorb the extra costs, is irresponsible.”

For an explanation of how What Car? carries out True MPG testing, click here.

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Symanski 6 February 2014

Might as well add water!

I used to run V-Power all the time. It cost more, but you got more MPG. I do the same journeys to work all the time; easy to compare. Then I noticed less power and less MPG. It was like normal petrol, not the expensive V-Power. I wrote to Shell asking them about it and they replied stating it was now remixed to contain Biofuel. That 5% they had to add took 7% off my MPG, maybe more. So what's the point? You've gone to the expense of creating this fuel, burning fuel in the process, to get a fuel which makes your car less efficient. There is absolutely no point in using more Biofuel to "greenwash" transport when the end result is that you don't use any less of the base petrol! Water may not burn, but at least it freely drops from the sky. I've never bought V-Power since.
Shane_2005 6 February 2014

I used this on my brand new

I used this on my brand new (had done about 700 miles) Fiat 500 TwinAir last summer when I drove across France. Didn't realise what I had put in the car until it was too late and the tank was full.

I panicked and was terrified the car wouldn't start. Needless to say the car then proceeded across France just as happy as 95' petrol.

A non issue.

Suzuki QT 6 February 2014

Hmmm ...

E5 ... E10 ... E100!!! ... It's all a moot point given that China is pumping out CO2 like there's no tomorrow ... That said, I'm certain of the big smile on the Government's face at another wheeze to wring more tax money from the motorist ...