How long does heating oil keep?

[MM]

Because of the warm weather I still have quite a bit left from the last delivery in January.

MM

[Grunff]

Many, many years. Unlike petrol it has hardly any volatiles in it, so not much is lost.

After a decade or two there may have been a measurable amount of polymerisation - but that's about it.

[Mr Fizzion]

Doesn't it go rancid?

[John Schmitt]

It is a mixture of alkanes, not alkenes. Triglyceride fats are the ones prone to going rancid, and then those which are less saturated, i.e. have more double bonds per molecule. Typically thes are animal fats, although there are exceptions.

John Schmitt

[Chris Bacon]

It'll be fine.

[Dave Fawthrop]

| On Thu, 27 Oct 2005 12:10:52 +0100, Grunff wrote: | | >MM wrote: | >> Because of the warm weather I still have quite a bit left from the | >> last delivery in January. | >

| >Many, many years. Unlike petrol it has hardly any volatiles in it, so | >not much is lost. | >

| >After a decade or two there may have been a measurable amount of | >polymerisation - but that's about it. | | Doesn't it go rancid?

You do not drink the stuff, you *burn* it ;-)

[Rob Morley]

... unless you're starting a siphon the old-fashioned way - then you belch it for days afterwards :-)

[Newshound]

For the next hundred million years or so.

[Mr Fizzion]

Thanks for the technical answer....I should have used a smiley since it wasn't a serious comment!

Animal fats have typically more saturated fat content than vegetable oils that are liquid at room temperature, and are thus less prone to going rancid.

Mr F.

[John Schmitt]

As in butter vs. margarine?

John Schmitt

[Mr Fizzion]

Not sure what butter contains exactly but it certainly contains water and milk solids as well as fat. Not sure if that helps it go rancid.

"Traditional" margarine has no carbon double bonds in it because the vegetable oil in it is hydrogenated meaning that hydrogen gas is bubbled through it at a very high temperature and pressure in the presence of a nickel catalyst. This produces trans fatty acids rather than the natural cis form which are implicated in all manner of health problems.

Mr F.

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember MM saying something like:

Uncontaminated oil will keep for years. Problem is, very few tanks are clean and there's a bacterium lives in the bottom which will make your oil slimey if it's in there for long enough.

You can get biocides to deal with this if it's a problem, but you have to clean the tank out first if it's bad.

Having said that; chances are yours is fine. Draw off a sample to see what it looks like.

[Nigel Molesworth]

Lucky bugger, I've just paid 39p per litre :(

[Chris Bacon]

How do the various options compare, i.e. the relative costs of oil, natural gas, anthracite, LPG, electricity? Anyone?

[MM]

It's still doing the business as far as the boiler is concerned. Every day, for one half of an hour early in the morning, it heats my water just enough to do the washing up. An occasional 10 minute boost three times a week from the immersion heater is enough to get me a nice hot bath.

And I always thought oil central heating was expensive! (Must be the excellent insulation in this brand-new house.)

MM

[John Schmitt]

It is the butyrates. Once I got butyric acid on my hand and the smell hung around me for days. Marvellous, smelling of rancid cheese with no amount of washing removing it.

Hydrogenation is specifically to remove double bonds in the carbon chain. Single bonds cannot exhibit cis/trans isomerism, can they? The nickel catalyst works by adsorption of hydrogen which then becomes labile to sterically unhindered double bonds.

John Schmitt

[doozer]

Nope, only double bonds exhibit cis/trans isomerism. Having said that you can end up with a preferred orientation in a single bond if you have sufficiently large groups on either end. AFAIK anything in liquid form should have enough energy to rotate around a single bond.

[Nigel Molesworth]

At one time, oil was much cheaper, but now is about the same as LPG. Don't know about NG, but is suspect that electricity (especially off-peak) is the cheapest, as it doesn't rely so much on oil.

[Dave Liquorice]

Very volatile oil prices ATM, assuming a price over 30p/l your looking at 3 to 4p/kWHr. Don't know what bulk LPG prices are these days

Even with the current price rises it's still only about 2p/kWHr

Off peak is between 3 and 4 p/kWHr, ordinary domestic rates anything from 6p to 12pkW/Hr (it pays to shop around these days).

[MM]

Some properties I am considering now have electric night storage heating, which used to be the most expensive (allegedly). But I wonder whether that is indeed the case any longer?

When perusing property details/photos now one of my main checkboxes is, has it got a real chimney? I reckon I wouldn't need to fork out very much to get enough wood to burn on an open fire (or in a stove) for the whole winter, as we used to when I was a boy. Near me there's a dilapidated wooden shed (completely collapsed) which I'm sure the owner would let me take away for a few quid.

MM