Shell petrol stations.

[Overlag]

Like so many things how you drive and where will affect the impact of having a full tank vs say a half tank. On most cars thats going to be 20-30kgs. so very low single digit % increase in car weight

If most of your journey is spent in stop start etc your probably going to see no diff, as your wasting the vast majority of the energy being produced anyway.

If your cruising along at a fixed speed then any extra weight will require more energy to keep its momentum.

its actually the other way around. Stop start driving will suffer with a heavier car more than cruising on a motorway.


I cant believe this thread made 7 pages.

 

[Simon]

8

 

[Raymond Lin]

I drive literally right past a Shell every day to and from work, but I still hate filling up. I'm happy to take that minuscule MPG hit in order to carry around more fuel. I'd be happy if my tank was 200 litres then I'd have to do it even less often.

Are you really citing a bloke from a speed awareness course as an authoritative speaker on the subject? lol

I’m citing physic.

 

[Mercenary Keyboard Warrior]

Aerodynamics is the enemy at speed. Not weight.

Stop start driving is where accelerating mass takes the hit on fuel economy

Its both, but aerodynamics is the larger impact at speed for sure. But yes for sure as speed goes up you will see far more effect from wind resistance etc. Physics also of course tells us that accelerating 10% more weight will require 10% more energy.

The problem is there are so many factors at play that the insignificant benefit from having slightly less fuel weight will disappear in our ability to measure it.

Car engine efficiency, not a straight line, plus doesn't start at zero unless we use stop start somehow perfectly
Aerodynamics as you say assuming pure car design here
Friction of eg tyres, transmission

But anyway if we go back to the worst case for us, where we are accelerating and adding energy, if 30kgs average extra weight. Lets take the lightest focus, 1322kg and add a lightweight driver of 60kg, giving us 1382 plus lets say a 18kg of fuel to nicely round us to 1400kgs. So if 30kg would top it up we would be 1430/1400 = 2.1% heavier and require 2.1% more energy usage.

So if we ignore any effect at all from anything other than accelerating and lets say we spend 25% of the time actually accelerating 25% of 2.1% is 0.5%. Hardly seems worth worrying about does it

Personally I hate petrol stations so the less frequently I nee to go to one its worth the miniscule impact on MPG. AND, I seem to get range worries now so I would struggle with only having 100miles range when I had just "filled up"

 

[Beansprout]

Does it make the lawnmower quicker, run better and help with the longevity of the engine!?

Nah but he gets more grass per gallon

Brilliant

As for the results I've no idea, I'll ask the gardener, will need to wait until summer though. The thing does a scorching 7mph on standard fuel, so....maybe 7.5? 8??

Of course I only fill it up halfway in order to keep weight down and get the grass done quicker.....

 

[Liquidfox]

Yeah because anyone's opinion that differentiates from the *popular people* on these forums is considered a nutter. Especially in motors.

Just to add to this thread. For the sake of argument I tried a different shell today out of town, and had no issue with putting in £20.00 - this had a newer pump with a very sensitive handle so I can only imagine it's all in the handle of the stations that I visited and not some conspiracy I implied it to be.

Nothing at all to do with the price of the fuel being different, therefore rounding coming into effect again as others have said multiple times.

 

[Jumper118]

i never fill my car up fully, will just give the car more momentum through the wall, so whats the point?

 

[LeeUK]

I only put about £20 in and usually lasts me 2 weeks+ of going to work and back. Only ever brim the tank if I'm going on a long journey like a 400 mile round trip, even though the last time I did that I still had just under half a tank left.

Always use pay at pump where possible too. Hate places that require you to go and queue up in a forecourt shop + these type of places you usually have to wait for a free pump because of people doing their shopping in the said shop.

 

[sigma]

Its both, but aerodynamics is the larger impact at speed for sure. But yes for sure as speed goes up you will see far more effect from wind resistance etc. Physics also of course tells us that accelerating 10% more weight will require 10% more energy.

The problem is there are so many factors at play that the insignificant benefit from having slightly less fuel weight will disappear in our ability to measure it.

Car engine efficiency, not a straight line, plus doesn't start at zero unless we use stop start somehow perfectly
Aerodynamics as you say assuming pure car design here
Friction of eg tyres, transmission

But anyway if we go back to the worst case for us, where we are accelerating and adding energy, if 30kgs average extra weight. Lets take the lightest focus, 1322kg and add a lightweight driver of 60kg, giving us 1382 plus lets say a 18kg of fuel to nicely round us to 1400kgs. So if 30kg would top it up we would be 1430/1400 = 2.1% heavier and require 2.1% more energy usage.

So if we ignore any effect at all from anything other than accelerating and lets say we spend 25% of the time actually accelerating 25% of 2.1% is 0.5%. Hardly seems worth worrying about does it

Personally I hate petrol stations so the less frequently I nee to go to one its worth the miniscule impact on MPG. AND, I seem to get range worries now so I would struggle with only having 100miles range when I had just "filled up"

What about the extra stop and starts introduced by extra visits to the pump? And the increased idling time waiting for a pump to be ready? Increased wear and tear of the car? You're using the clutch more often etc.

If putting £20 in means you're going 3x more often to the pump for the same volume of fuel the increased impact over the liftetime of the car must be insane.

 

[Haze]

its actually the other way around. Stop start driving will suffer with a heavier car more than cruising on a motorway.


I cant believe this thread made 7 pages.

I carnt belive this even a thread, op needs to get a life

 

[The Running Man]

Fwiw I put a tenner in every 7-10 days

 

[Orionaut]

LMAO those Indian's sure know how to work! It's like that at our local petrol station's, all of them. Indian's must have a monopoly!

They might well do

I remember a claim some years ago that basically once a retail outlet goes into Indian/Asian ownership (It was Ugandan Asians originally) it never goes back.

They have their own internal networks for selling on businesses and non-Asians dont get a look in.