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In times of plenty one could notionally compress incoming domestic gas into cylinders using electric compressors.

Is this legal?

Would it be worthwhile?

Could you compress enough gas in a reasonably sized cylinder to, say, cook a decent meal on a standard cooker?

Vortex wrote:In times of plenty one could notionally compress incoming domestic gas into cylinders using electric compressors.

Is this legal?

Would it be worthwhile?

Could you compress enough gas in a reasonably sized cylinder to, say, cook a decent meal on a standard cooker?

You'd be better of going out and buying some bottled butane or propane and the relevant camping stove to go with it. Safer than compressed methane! Propane also gives the highest Btu per unit of liquified gas of the three, and requires the least compression. Liquid methane is usually transported in cryogenic tanks, so I imagine the compression would have to be extremely high to liquify it at room temperature.

Dunno about the legality, but I did see a unit advertised here in the U.K. many years ago, for just that purpose. It's "blurb" was how much you could save by re-filling your own gas bottles if you bought this gadget. Can't remember any more - but I do remember wondering if the thing could over pressurise the cylinder......

Mitch wrote:Dunno about the legality, but I did see a unit advertised here in the U.K. many years ago, for just that purpose. It's "blurb" was how much you could save by re-filling your own gas bottles if you bought this gadget. Can't remember any more - but I do remember wondering if the thing could over pressurise the cylinder......

Oh no, that's certainly not possible. As we speak I'm compressing methane to over 500 Bar. No problem, it's perfectly sa........

You could try the Chinese method - uncompressed....

Ah, good idea. I happen to have a secondhand bus which in the last few minutes I have converted to house gas:

You'd need an industrial pressure vessel (a hundred and something bar tested) or you'd need to cool it to -160oC (but if you did that it'd make a really neat freezer!).

But it'd take so much electricity what's the point. Some of the peak shaving plants the old British Gas experimented with in the late 80s (which liquefied gas overnight to meet daytime peaks) were so inefficient the whole idea was called off and they kept the gaometers as being the far more efficient option.

From my caravanning days, you could get a kit to convert the gas bottles in your 'van to be refillable at GPL service stations, which was much cheaper at the time.

mobbsey wrote:You'd need an industrial pressure vessel (a hundred and something bar tested) or you'd need to cool it to -160oC (but if you did that it'd make a really neat freezer!).

Yes, CNG or LNG, that is the question. Either way it's going to be risky and expensive, and I wouldn't be too happy if one of my neighbours were messing about with such things!

Whilst it is undoubtably possible to commpress natural gas and store it in cylinders, it is unlikely to be worth the effort, and I am uncertain as to the legality.
Unlike butane or propane, natural gas can not be liquified by pressure alone, the amount that can be stored in a cylinder is therefore very limited.
The only cheaply and readily available gas cylinders are those intended for butane or propane, these have a relativly low working pressure, I think less than 10 bar for propane.
If a cylinder has a volume of 25 litres, and is charged to 8 bar, then the effective volume stored is 200 litres, or one fith of a cubic meter, which is not much.

And anyway why would you want to do it?
When a portable gas supply is required, for outdoor or temporary use, or to power a vehicle, then butane or propane should be considered.
For domestic standby use, there appears little point, short term or rota gas cuts are most unlikely for safety reasons.
If the gas is cut of longer term, then the amount that could be stored would be so quickly exhausted, that coal, firewood, kerosene, or proper bottled gas would be more use.

To return to the original question, yes you could cook a meal, perhaps several meals, but without an improbable number of cylinders, not many meals.
The compressor would be a costly article, and would need electrcity or other power, the money could probably be better, and safer spent on other fuel stores.

SAFETY NOTE, PLEASE DO NOT TRY IT, unless you have very considerable experience in such matters.

Yes it is possible and quite legal to run CNG cars. The pump costs about ?2K and will slowly (5 to 6 hours) fill your tank in your car to 200psi. The car conversion costs the same as an LPG conversion at about ?2K as well. So 4K for the whole setup. They say you will be paying the equivalent to 25p a litre. Not sure where the taxman fits in though....

You can get tri fuel cars as well (LPG,CNG and petrol).

Your mileage will be reduced as the calorific value is lower than petrol (30% lower I think). The tank will not take you very far as it is compressed rather than liquified. So less energy per volume stored.

Info here: http://www.ngva.co.uk/