Petrol prices

andy88_2

Stonk wrote:

The rise in pump prices should be much much less that the corresponding rise in oil price.

It is. Oil prices have risen by a factor of more than double in recent years

withabix

RedOnRed wrote:

I'm more annoyed about the price of diesel right now.

Why on earth should it be around £0.05 a litre more then petrol when we all know that diesel can be synthetically made?

I could walk down my local chippy right now, get some old fat off them, strain it and add a few basic chemicals and i'd have a perfectly useable diesel substitute.

That being the case then diesel should be the cheapest and most eco friendly option and shouldn't be liable to all this price per barrel rubbish.

Diesel is more expensive at the moment because there is only a limited quantity which they can distill and crack from a 'barrel' of oil. As petrol is molecularly smaller, they can break the molecular chains in your 'barrel' of oil further, thus obtaining more usable product.

As the chinese and other far eastern economies are booming, plus the small matter of our botched attempt at taking over Iraq, demand is at an all-time high and supply is limited.

Thus, diesel is more expensive than petrol.

Also, it may well be possible to produce synthetic diesel, but that would be far more expensive than that obtained from crude oil - you probably wouldn't need the decimal point on the price per litre - it would probably be 899p rather than 89.9p. Also, the base organic chemcials required to make the synthetic diesel would come from....oil, coal or gas mainly.

The chip-shop 'diesel' isn't diesel, it's just something that will burn in a diesel engine due to similar properties, although it is a bit thicker.

IF we all started burning vegetable oil, what do you think would happen to the price of that?? Supply wouldn't meet demand. Tax would be added and bingo, demand and tax would give you something costing around.....errr 90p/litre!

withabix

Zippy123 wrote:

Tesco round up in all cases I have just checked a dozen or so receipts from last month. If it is £26.141 they will round up to £26.15. This seems a bit unfair, I would expect a round up or down to the nearest penny - not always a round up!

Not as simple as this.

Think about it. The £££ figure on the pump is driven by the volume figure. If the price was rounded up from the volume dispensed, you would expect the total price displayed on the pump to change by +1p after you had replaced the nozzle. That doesn't happen!

Currently, given that both price and volume are displayed to 2 decimal places and that fuels (in most places) costs less than £1/litre, then the 'rounding up' balance is biased towards the volume, as the volume figure changes faster than the price figure.

Once the price exceeds £1/litre, then the price figure will change faster than the volume figure, at which point the rounding bias will be the other way.

In other words, currently, ignoring permitted accuracy tolerances on dispensing fuel, all rounding will be DOWN, as you can dispense a very small quantity of fuel without the cost changing. Try it and see - you probably do it already if you try and buy to price (eg exactly ten quids' worth) rather than to volume (fill to first click etc).

IvanOpinion

Zippy123 wrote:

Tesco round up in all cases I have just checked a dozen or so receipts from last month. If it is £26.141 they will round up to £26.15. This seems a bit unfair, I would expect a round up or down to the nearest penny - not always a round up!

I think you can recover this amount either by using a petrol station closer to home or by applying slightly less pressure on the accelerator while going round a corner. I think the amount is so trivial as to be irrelevant ... ir probably cost you more in time to check your receipts than it did to pay the extra 0.5p (on average).

Andy88 wrote:

I doubt if that was ever true; certainly not in the last 30-40 years anyway.

It is a figure I remember from the 70's - maybe it was simply a case that they could not reliably make pumps more accurate than this back then?????

Ivan

Wig

Hi evry1,

Zippy, My tesco reciept shows a round down here:
66.01 li @ 85.9p = 56.70

Iainkirk,
It doesn't always round down, the price doesn't change after you have stoped pumping because the price is allready displayed in pence and the computer automatically adjusts the price depending on how much fuel is dispensed (rounding up or down as it goes), which is why as you say you can get a bit more out without increasing the price.

I once filled a 25 litre see through container with fuel, I had previously marked with a 25 litre line, can't remember how I measured it prior, I think i had filled it with water using a 5 litre water bottle (accurately marked). I was surprised to see that 25 litres on the pump hit my line spot on!

andy88_2

iainkirk wrote:

The chip-shop 'diesel' isn't diesel, it's just something that will burn in a diesel engine due to similar properties, although it is a bit thicker.

IF we all started burning vegetable oil, what do you think would happen to the price of that?? Supply wouldn't meet demand. Tax would be added and bingo, demand and tax would give you something costing around.....errr 90p/litre!

When transesterified the viscosity is very similar.

Tax is added. Retail costs are similar, despite a 20p/litre tax advantage.

RedOnRed

iainkirk wrote:

The chip-shop 'diesel' isn't diesel, it's just something that will burn in a diesel engine due to similar properties, although it is a bit thicker.

IF we all started burning vegetable oil, what do you think would happen to the price of that?? Supply wouldn't meet demand. Tax would be added and bingo, demand and tax would give you something costing around.....errr 90p/litre!

I'm talking about a synthetic diesel substitute which has nothing to do with drilling and barelling.

What ever the standard and grade of chip shop "diesel", the point is it works and is sustainable because it's derived from something that can easily be reproduced and isn't an inexhaustible natural supply.

"Burning vegetable oil" would have no impact on OPEC having everyone by the balls price wise and why wouldn't supply meet demand? When was the last time any where ran out of veg? Farmers would be happier too.