Hi Saz,
Many thanks for your input, greatly appreciated.
Kind regards
Doug
I’ve been finding E10 isn’t denting my fuel economy as badly as I expected. It ought to drop due to the lower energy density of the ethanol.
Several tanks of E5 Shell V-power in a row got me 52-53 mpg. Several tanks of Sainsburys E10 got 51 mpg. (This isn’t in my MX-5 but in our little Fiat Panda, which I’ve been commuting in since the London low emission zone made it £12.50/day to take the '5 to work). That’s the same sort of difference that 95 RON vs high octane makes in that engine anyway, without the ethanol difference. (Someone previously linked to a study showing real-world tests which just happened to include a Panda as one of the tested cars, and it got around 2-3% better mpg on the higher octane fuel.)
It did occur to me that we don’t actually know what percentage of ethanol is being put in the fuel, only that 10% is the upper limit.
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I’m just about empty on the first tank of E10 (Shell) in my VW Up having done approx 330 miles since I filled it up. I use the car for short commutes and the odd longer drive and usually average around 360 miles per tank on E5 premium and closer to 390 on super.
Hardly scientific, but on the basis of this one tankful of E10, I’ll probably stick to E5 in future.
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I think I lot of people are noticing a reduction in mpg with E10. I don’t do any scientific measurements with my Audi but on a regular 80 mile trip it looks like my typical 50 mpg is more like 45 which begs the question what was the point of it as we’ll all just end up using more fuel so no reduction in fossil fuel consumption at all.
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Clearly that’s not what they expect to happen. Yes the mpg is expected to drop because ethanol provides less energy per unit volume than petrol does, but you should still expect to get as much distance as usual from the 90% petrol in the fuel plus somewhat less distance from the 10% ethanol.
Like I said, I’m seeing two or three percent reduction overall.
The Jaaag has dropped from an average 33mpg on a motorway run to sub-30mpg, so now the V8 is about the same as my NA MX5.
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Seems to be similar comments of most car forums I’m on. My daily a 1.6 new model Vitara on our normal cylcle was always averaging 43-44 mpg, on E10 dropped to about 37. Last two tanks have put in Momentum E5 and back up to pre E10 mpg.
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UP! GTI, bought new last year, 4000 miles, always used 99/97 super unleaded, lifetime MPG 54.6.
2 tanks of E10, about 700 miles, and consumption is now showing 48.4, so it’s now doing 6.2 MPG less on E10 - over 10%. I’ve done a few brim to brim checks, and the numbers are accurate.
Same mixed use, including some 50mph M27, and some 40 minute crawls to work in traffic.
Stop Start always off.
I wonder how much more revenue the oil companies, retailers and HMG are getting, assuming most cars are similarly affected.
Spreadsheet time
The “fuel component” goes now to the oil company and a company providing the bioethanol
If 100% oil petrol was the same price as now, and you now have 10% worse fuel consumption now, then revenue returned wholesalers (oil) is 6.7% less.
Unless the oil companies start buying up these bioethanol companies, and they might, then revenues, subject to usual oil proce fluctuations, will decline.
The interesting thing to consider the cost of oil was a significant determiner of the price at the pump, and the oil price is affected by all sorts of macroeconomic impacts, from halfway across the world. But bioethanol in Europe is largely made from European sugarbeet and waste. The notable exception is he main British supplier, where much of the sugar will have come from Mauritius an some other countries. I’m not of the linkage of sugar commodity prices and oil, or is there is even a commodity price for “agricultural waste” (I assume its traded).
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A different question about the E5/E10 fuels:
When it comes to MOT test time and the car’s emission levels are going to be examined, is one fuel going to give better results than the other?
Some probably unrelated experience - I’ve been running on Tesco 99 since May of last year.
They ran out a week or two ago where I am, so I had to put in 95 to get home since tank was nearly at the E.
I put in about half a tank of it since I wasn’t sure when they would stock up again and the car refused to start the first two times I tried, which is something it never does. And then it didn’t seem too happy with it for a minute or two and then it ran pretty much the same after.
I’m not sure why this is, I’m not familiar with how the engine management works so I have to only assume the ECU was re-learning how to make explosions.
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I haven’t put any E10 in the NC MX-5. I had to put a tankful in the CX-5 during the panic buying last year, when there was no E5 anywhere. The CX-5 was noticeably down on power, requiring 5th gear on hills it would normally climb in 6th. Horrible stuff.
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Where did you find that? Unless you’ve added forced induction, all MX-5s only need 95 RON.
there is a label on the underside of my fuel flap that says fill with super
Need means it will run on the stuff, not necessarily that it will run well.
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Is it a US model? Super over there is similar to normal unleaded here. They have a regular grade which you wouldn’t put in an MX-5.
no it is a UK car!
definatly not an import!
I think that’s French or something, doesn’t it say Super sans plomb or something? On the continent Super is our normal fuel isn’t it?
That sticker actually says a lot of things, un leaded premium,bleifrei super,super sans plomb, min 95 octane / Ron.
Things have changed and now premium unleaded is 95Ron super unleaded is 97/98 Ron then there are the “Premium” 99 Ron fuels like Shell and Esso. As long as the fuel is min 95 Ron then in the UK at least it is suitable, anything else is your choice.
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