Any truth in this ?

[truthfindergeneral]

Email doing the rounds


TIPS ON FILLING YOUR CAR

I don't know what you guys are paying for petrol..... but here in Durban we are also paying high prices, up to
R 8.50 per litre. My line of work is in petroleum and has been for about 31 years now. So here are some tricks to get more of your money's worth for every litre.

Here at Marian Hill Pipeline where I work in Durban, we deliver about 4 million litres in a 24 hour period thru the pipeline. One day is diesel, the next day is jet fuel, and petrol, LPR and Unleaded. We have 34 storage tanks here with a total capacity of 16,800,000 litres.

Only buy or fill up your car in the early morning when the ground temperature is still cold..

Remember that all Service Stations have their storage tanks buried beneath the ground. The colder the ground the more dense the fuel. When it gets warmer petrol expands, so buying in the afternoon or evening .......... your litre is not exactly a litre. In the petroleum business, the specific gravity and the temperature of the petrol, diesel, jet fuel, ethanol and other petroleum products play an important role. A one degree rise in temperature is a big deal in this business but the Service Stations do not have temperature compensation at the pumps.

When you are filling up do not squeeze the trigger of the nozzle to a fast mode.

If you look you will see that the trigger has three (3) stages; low, middle and high. In slow mode you should be pumping on low speed, thereby minimising the vapours that are created while you are pumping. All hoses at the pump have a vapour return. If you you are pumping on the fast rate, some of the liquid that goes into your tank becomes vapour. Those vapours are being sucked up and back into the underground storage tank so you're getting less worth for your money.

One of the most important tips is to fill up when your tank is HALF FULL.

The reason for this is, the more fuel you have in you tank, the less air occupying its empty space. Petrol evaporates faster than you can imagine. Petroleum storage tanks have an internal floating roof. This roof serves as zero clearance between petrol and the atmosphere, so it minimises the evaporation. Unlike Service Stations, here where I work, every truck that we load is temperature compensated so that every litre is actually the exact amount.

Another reminder. If there is a fuel truck pumping into storage tanks when you stop to buy, DO NOT FILL UP. Most likely the petrol/diesel is being stirred up as the fuel is being delivered and you might pick up some dirt that normally settles on the bottom.

Hope this will help you get the most value for your money. Rember to always fill your car when the tank shows 'half'. Always fill up in the early morning. Always fill up in slow mode.
:|

 

[horgantrevor]

thanks food for tought makes sence

 

[Ellsy Tanners]

Not to sure about this, i believe the effort reqiured to carry around 20-30kg of fuel that you are not using will compensate for the small gains in the amount you get.

I have been told not to fill more than half of your tank to save weight.

 

[jberks]

Not to sure about this, i believe the effort reqiured to carry around 20-30kg of fuel that you are not using will compensate for the small gains in the amount you get.

I have been told not to fill more than half of your tank to save weight.

Precisely - yes - it will evaporate to some extent but as you say, the extra fuel required to carry round the extra weight is probably equivalent.
Again, yes fuel is more dense in the morning - but - the tanks are in the ground and the ground does not heat up or cool down very quickly - (hence ground source heat pumps) so in reality the temp difference, especially in the UK will be minimal.
The vapour/speed argument - You could argue the opposite, The faster you pump, the quicker it reaches the tank and the less time spent travelling down the filler neck surrounded by air and hence evaporating.

The point is, for most of us, with 50-70l tanks I'd suspect the difference is less than pennies - even at today's prices. Ok - it may make a small difference if you're a garage selling thousands of litres, but to us, using maybe 140l per month and filling every 2 weeks or so - nah - pennies. You'll save more just coasting into the garage or not tearing off at the lights once per fill up.

 

[jon_harley]

Precisely - yes - it will evaporate to some extent but as you say, the extra fuel required to carry round the extra weight is probably equivalent.

It's way, way more. If you only ever fill up to half full, and always run between half empty and empty, you'll be driving a car that's 30kg or more lighter and that'll save far more fuel than you lose to evaporation in the lifetime of the car.

Yes, petrol evaporates more quickly than water, but it still takes a long time to become a measurable amount. Leave the top off a petrol can for half an hour and you won't be able to see any difference in volume, or measure any weight difference with normal household equipment.

Again, yes fuel is more dense in the morning - but - the tanks are in the ground and the ground does not heat up or cool down very quickly - (hence ground source heat pumps) so in reality the temp difference, especially in the UK will be minimal.

Indeed. The whole thing is rubbish, in fact, except for the bit at the end about not filling up when the tanker is replenishing the tanks and stirring up sediment. Especially laughable is the advice to go fill up on a cold morning because you'll get more for your money - ever seen the MPG reading on cold mornings?

A much better money saving tip would be, cycle to the garage with a petrol can instead of using petrol to drive there!

 

[The German Flower Pot]

the way i drive it would make about 2 mins worth of fuel even if it was as bad as he says

last filled up £68, now use dhalf a tank and got 120 miles !

nice, i might aswell spash some on the floor and wave the nozzel around my haed for all the fuel i waste

 

[rf065]

I know modern electronic gas meters are pretty accurate and can compensate for the different temperatures of the gas passing through it to ensure the readings are accurate. I would be very surprised if this technology was not available in modern electronic petrol pumps too.

Russ

 

[psmart]

Having lived in South Africa for 10 years in the Transvaal and Orange Free State, the ground can get very chilly during a clear night and rapidly cools off (you could live off the dew in the morning for example) and the day can get very hot making it difficult to walk around in bare feet, but a storage vessel buried deep underground shouldnt be affected as much by the intra-day temperatures, and Durban (where the guy works) is very moist and humid almost all year round, not really chilling off during the night, so temperature variations from where the guy works would be minimal!

If you filled up when it was cold, then as the day grew warm, where would the expanding fuel go? The fillers on petrol tanks have a pressure release valve, so vapour or even fuel would leak out, surely?

The weight is an issue as well, more weight=more burnt fuel, so this leads me to believe its a scam put forward by the beneficial parties of petrol sales.

Something you may/may not have noticed in the UK, but here in Germany, the traffic lights always went to flashing amber outside of peak periods, so people used their common sense and traffic flowed, not so now! Even at midnight, you still wait, burning fuel at the greatest polluters invented by man! Who benefits, safety?, pedestrians?, car drivers?, no, the government and supply chain, more especially as the commodity traders have pushed up the price so high! Its also noticeable that Germany is now one big roadwork, with speeds down to 60kmh or 40mph, causing massive tailbacks and of course, additional burnt fuel!

One saving grace, fuel came down 10c (8p) this week to EUR1.44 litre as fuel prices still skyrocket .... perhaps the German government is listening! Very much doubt thieving Brown would do the same in the UK!

 

[davidsl500]

For the record, the first 4m depth of ground is susceptible to temperature variance and after that the next 100m is pretty stable all year round and if you are interested, the next 100m after that is considerably warmer due to radiactive decay.....

How deep are Petrol station tanks buried ? I presume they would be bridging the 4m/100m range.

 

[whitenemesis]

Read this recently
"The minor differences due to temperature are more than outweighed by the fact that diesel fuel has a significantly higher density than petrol - it's about 12% more dense. However it has the same calorific value so, because fuel is purchased by volume, a diesel driver gets 12% more mass and therefore 12% more energy in each litre - which accounts for a lot of the 'economy' benefits of the diesel engines"

The depth of the storage tank, the turnover of fuel stored etc all complicate any calculations

 

[3146bj]

For the record, the first 4m depth of ground is susceptible to temperature variance and after that the next 100m is pretty stable all year round and if you are interested, the next 100m after that is considerably warmer due to radiactive decay.....

How deep are Petrol station tanks buried ? I presume they would be bridging the 4m/100m range.

The top of the tanks are at least 2 feet below the surface and the bottom may be 14 feet or more below ground. The diurnal variation in product temperature is very small, maybe 1 or 2 degrees, PROVIDED no product is added. In winter here in Australia, the product temperature is around 12-14 in underground tanks, if no product is added. However, product delivered may be up to 18-20 degrees depending on the ambient air temperature as it is delivered ex above ground tanks which heat and cool much more quickly and may have warm fuel added ex the refinery.

The thermal expansion/contraction is so small in the volumes dispensed into individual cars that it can be ignored (co-efficient of thermal expansion is around 0.000015 per degree C).

How do I know? Try 30 years chasing losses in the oil industry!