Van owners: LPG is dying, let's talk biomethane! - Nick H.

Are there many people here interested in LPG's problems? I'm no expert, but here's my take. I'm interested because I have a petrol Nissan Elgrand people carrier and want to live in it, criss-cross Europe in it, be kind to the climate and not spend too much on fuel.

LPG sales at filling stations are so tiny that filling station owners are removing LPG pumps to make space for EV chargers. And LPG prices have gone up a great deal. So if you have a petrol or diesel engine, LPG conversion is not nearly as attractive as it used to be. The govt doesn't care. They're never going to help the LPG market with favourable tax rates.

But biomethane is coming to the rescue, sort of. Biomethane is functionally the same as methane and Compressed Natural Gas (CNG). It's very eco-friendly. Made of straw bales, cow s*** and other things. Burns even more cleanly than LPG and bioLPG. Many big HGV fleets in Europe (inc. Waitrose, M&S and Royal Mail) are converting to it, because EVs are just not practical for long distance trucking. Governments are backing it. It's cheaper than LPG. In the UK, biomethane duty is fixed until 2032. Hundreds of filling stations are being built across Europe.

BUT right now there are only 14 publicly accessible biomethane filling stations in the UK. And biomethane needs a 3x bigger tank than LPG. Cars typically have a decent range with a LPG tank like a donut which goes in the spare wheel well. But for biomethane you need at least a 150 litre tank. Plus, the tank is very, very heavy. And the conversion kit costs more to buy and install.

A few car owners are sacrificing all their boot space in countries where methane is dirt cheap. But in the UK and Europe it's thought that biomethane will never catch on with car owners. It will be strictly a van or truck thing. Having said that, biomethane is so new that nobody really knows what will happen.

CNG has an excellent safety record. Unlike LPG it doesn't stop you using the channel tunnel.

I repeat, I'm no expert on this stuff. If there are any experts here I'd be delighted to have my mistakes corrected.

Edit: back in 2017 VW were selling a purpose-built CNG-fuelled van. The Parkers review is fascinating

www.parkers.co.uk/vans-pickups/news/2017/volkswage.../

Edited by Nick H. on 18/03/2024 at 15:08

Van owners: LPG is dying, let's talk biomethane! - Adampr

If there is a market for heavier, more expensive, lower range, lower carbon, cheaper to run vans, I think BEV had that sewn up.

Van owners: LPG is dying, let's talk biomethane! - Terry W

Biomethane is not a wonder gas.

The net zero argument is that it locks away CO2 in vegetation as it grows, which is then released as it is burnt.

It has some possible advantage in that it avoids release of methane were the vegetation allowed to rot naturally. Offsetting this - methane remains in the atmosphere for ~12 years, CO2 for centuries.

It is a little like plant derived ethanol which which removes CO2 during growth, then releases it when burnt. Both are limited as they cannot ever be 100% efficient simply because of processing and distribution losses.

Van owners: LPG is dying, let's talk biomethane! - Nick H.

The net zero arguments for biofuels always make my head hurt. Does the C02 cycle vary much with the choice of biomethane "ingredient"? I've read they use cow dung, dead cows, and eggshells, amongst other things.

Van owners: LPG is dying, let's talk biomethane! - Terry W

The net zero arguments for biofuels always make my head hurt. Does the C02 cycle vary much with the choice of biomethane "ingredient"? I've read they use cow dung, dead cows, and eggshells, amongst other things.

Ultimately it makes no difference what "ingredient" is used in making biofuels - matter is neither created or destroyed. Two main issues - timing and the chemical cycle.

  • Bioethanol crops regrow each year. Wood grows for 20-200 years. Coal and oil need millions of years to form. They all lock up carbon until burnt.
  • on human timescales plant ethanol and timber could be regarded as net zero. Oil, coal and gas are on geological timescales.
  • if all growing, cropping, processing, energy came from "green" sources the process could be net zero. Little energy surplus may remain to benefit humanity - the land devoted to crop production may even negatively affect food supplies.

Gases have different lives in the atmospheric before natural processes eliminate any excess. Methane - 12 years (CO2 centuries) but is 28 times as powerful as CO2.

Quick wins come from reducing those greenhouse gases which make the most immediate impact on climate. The focus on methane gets quick benefits to reduce warming - even though over time it makes little difference.

Cow dung and cows are the indirect product of sunlight and vegetation. The dung is recycled grass over a (say) 24 hour period. The cow may lock up carbon for a few years.

Vegetation left to grow as grass, weeds, trees etc would ultimately have rotted and released methane. Choosing dung and dead cows as feedstock for biofuels may avoid only the short term but more immediately damaging methane stage.

The above is an over simplification of a very complex subject . Beware of the many purveyors of half truths supporting their personal agendas - sometimes well intentioned, sometimes (frankly) corrupt self interest.

Van owners: LPG is dying, let's talk biomethane! - Nick H.

Thank you. My head still hurts. Maybe I'll just use petrol and try not to think about it. It's made of fish and seaweed, so it's a biofuel.

Van owners: LPG is dying, let's talk biomethane! - focussed

"The above is an over simplification of a very complex subject . Beware of the many purveyors of half truths supporting their personal agendas - sometimes well intentioned, sometimes (frankly) corrupt self interest."

Here's some "corrupt self interest" on the subject of CO2 and methane from Dr Wilson Flood of the Royal Society of Chemistry and a chemistry education consultant.

SUMMARY A doubling of the amount of methane in the atmosphere with its present composition would produce a warming equal to only about one thirtieth of the warming produced by a doubling of carbon dioxide. At present rates of increase it would take about 360 years for atmospheric methane levels to double. Molecule for molecule, methane is 7 times more effective at being a greenhouse gas than carbon dioxide. Present changes in atmospheric methane levels pose no environmental risk whatsoever.

Abstract from climaterealists.org.nz/sites/climaterealists.org.n...f

Van owners: LPG is dying, let's talk biomethane! - Andrew-T

As far as the car is concerned, there will be a weight penalty to using methane because it boils at -160°C. That means it can only be kept liquid at a low temperature or under high pressure, calling for a heavy tank. Compared with LPG - mostly propane and butane - those are easily liquefied at ambient temperature. So you won't get a usefully large amount of methane in your wheel well.

Van owners: LPG is dying, let's talk biomethane! - Nick H.

I think I covered that. Maybe there's an argument for really going to town with CNG....fit a used 700 litre lorry tank. They're about £400 on ebay. Biomethane prices vary so much that you could then make a bit of a detour to stock up, and recoup a big chunk of the cost of conversion.

Van owners: LPG is dying, let's talk biomethane! - edlithgow

IIRC someone on the defunct bangernomics forum claimed to be compressing his own NG for vehicle use from his domestic gas supply. Not sure about the VED legalities, and the kit required was quite pricey and hefty, but running costs were very low.

Van owners: LPG is dying, let's talk biomethane! - gordonbennet

IIRC someone on the defunct bangernomics forum claimed to be compressing his own NG for vehicle use from his domestic gas supply. Not sure about the VED legalities, and the kit required was quite pricey and hefty, but running costs were very low.

The Morrisons i use for LPG has only just had the LPG pump and petrol pump on the same island replaced after some 9 months, where some clot managed to blow himself and siad pumps up inadvisedly trying to fill a gas bottle from the autogas pump, we don't need any more hare brained bodges.

Getting back to the OP the reason LPG sales are so low is because the fuel is in short supply everywhere for some reason, whenever it arrives there's constant refuelling going on as word gets about, if it wasn't being held back the sales would be far higher.

Edited by gordonbennet on 19/03/2024 at 16:37

Van owners: LPG is dying, let's talk biomethane! - RT

IIRC someone on the defunct bangernomics forum claimed to be compressing his own NG for vehicle use from his domestic gas supply. Not sure about the VED legalities, and the kit required was quite pricey and hefty, but running costs were very low.

The Morrisons i use for LPG has only just had the LPG pump and petrol pump on the same island replaced after some 9 months, where some clot managed to blow himself and siad pumps up inadvisedly trying to fill a gas bottle from the autogas pump, we don't need any more hare brained bodges.

Getting back to the OP the reason LPG sales are so low is because the fuel is in short supply everywhere for some reason, whenever it arrives there's constant refuelling going on as word gets about, if it wasn't being held back the sales would be far higher.

For the record, some LPG cylinders are designed to be refilled from Autogas pumps - eg Safefill - it's up to the filling station management whether they allow it or not, Morrisons generally do allow it.

Van owners: LPG is dying, let's talk biomethane! - edlithgow

IIRC someone on the defunct bangernomics forum claimed to be compressing his own NG for vehicle use from his domestic gas supply. Not sure about the VED legalities, and the kit required was quite pricey and hefty, but running costs were very low.

The Morrisons i use for LPG has only just had the LPG pump and petrol pump on the same island replaced after some 9 months, where some clot managed to blow himself and siad pumps up inadvisedly trying to fill a gas bottle from the autogas pump, we don't need any more hare brained bodges.

Thats LPG.

Different

People blow themselves (and other people} up with petrol too.

Molotov cocktails. Napalm. Naptha Launches

The last one was Iike a steam engine but used petrol instead of water as the working fluid.

(!)

Hot in fast US yachting circles at the end of the 19th century.

Then there's all those inherently unsafe nuclear power stations. Hare Brained Bodges R US.

But I personally dont currently need this particular hare brained bodge, since I dont have a car.

I do like a good hare brained bodge though...

Edited by edlithgow on 20/03/2024 at 11:54

Van owners: LPG is dying, let's talk biomethane! - Engineer Andy

I have visions of people attaching plastic tubes to cows' backsides and the other end to their car...

Jus' wonderin' if prolific baked bean eaters could contribute?

Van owners: LPG is dying, let's talk biomethane! - Terry W

There is nothing new in the world of gas powered cars - can't understand why they didn't catch on? gas cars ww2 - Google Search

Van owners: LPG is dying, let's talk biomethane! - badbusdriver

Maybe there's an argument for really going to town with CNG....fit a used 700 litre lorry tank. They're about £400 on ebay.

Are you aware how big a 700l tank is physically?. An Elgrand might not be a small car, but it ain't that big either. A tank that size would certainly fit in, but given you will be living in the car, it would severely impact the usable space.

Van owners: LPG is dying, let's talk biomethane! - Andrew-T

<< Are you aware how big a 700l tank is physically?.

Think of it as 0.7 cubic metres, add some extra pipework, and the picture may be clearer ....

Van owners: LPG is dying, let's talk biomethane! - Nick H.

Here's one www.ebay.co.uk/itm/186332749624

Say it's 55 x 55 x 230cm. It would make a handy bench.

[img]i.imgur.com/yQRjiiS.png[/img]

Dread to think of the weight though.

Van owners: LPG is dying, let's talk biomethane! - edlithgow

Here's one www.ebay.co.uk/itm/186332749624

Say it's 55 x 55 x 230cm. It would make a handy bench.

[img]i.imgur.com/yQRjiiS.png[/img]

Dread to think of the weight though.

Those appear to be diesel tanks. Not very relevant in the context of CNG or LPG, except perhaps as an example of A BIG THING.

A CNG or LPG tank would be more relevant. Perhaps one could use a general purpose gas bottle, if you could find somewhere to secure it..

Edited by edlithgow on 20/03/2024 at 02:06

Van owners: LPG is dying, let's talk biomethane! - badbusdriver

Here's one www.ebay.co.uk/itm/186332749624

Say it's 55 x 55 x 230cm. It would make a handy bench.

[img]i.imgur.com/yQRjiiS.png[/img]

Dread to think of the weight though.

Those appear to be diesel tanks. Not very relevant in the context of CNG or LPG, except perhaps as an example of A BIG THING.

A CNG or LPG tank would be more relevant. Perhaps one could use a general purpose gas bottle, if you could find somewhere to secure it..

As Ed says, that is a diesel tank.

Now I don't know enough on the subject to say whether it could be used to store gas.

But, having looked at a blueprint type image of an Elgrand showing the measurement from dashboard to the back of the rear seat and comparing that to the distance from the back of the front seat to where (I guess) the inside of the tailgate to be, I'm doubtful that tank would fit in anyway.

Setting that aside, I've done a little digging and if my info and maths are correct, 700 litres of CNG would come in at about 400kg. Can't find out how heavy an aluminium tank that size would be, but based on the weight of a similar sized baffled water tank (I'm a window cleaner), I'd guess 50-100kg. Point is, having that much weight lying along one side of the vehicle would make for very interesting handling characteristics. Also, how would you safely secure something that heavy on the inside of a car?.

I can't help thinking that a diesel van would be a better fit for what you plan to do.

Van owners: LPG is dying, let's talk biomethane! - edlithgow

Here's one www.ebay.co.uk/itm/186332749624

Say it's 55 x 55 x 230cm. It would make a handy bench.

[img]i.imgur.com/yQRjiiS.png[/img]

Dread to think of the weight though.

Those appear to be diesel tanks. Not very relevant in the context of CNG or LPG, except perhaps as an example of A BIG THING.

A CNG or LPG tank would be more relevant. Perhaps one could use a general purpose gas bottle, if you could find somewhere to secure it..

As Ed says, that is a diesel tank.

Now I don't know enough on the subject to say whether it could be used to store gas.

But, having looked at a blueprint type image of an Elgrand showing the measurement from dashboard to the back of the rear seat and comparing that to the distance from the back of the front seat to where (I guess) the inside of the tailgate to be, I'm doubtful that tank would fit in anyway.

Setting that aside, I've done a little digging and if my info and maths are correct, 700 litres of CNG would come in at about 400kg. Can't find out how heavy an aluminium tank that size would be, but based on the weight of a similar sized baffled water tank (I'm a window cleaner), I'd guess 50-100kg. Point is, having that much weight lying along one side of the vehicle would make for very interesting handling characteristics. Also, how would you safely secure something that heavy on the inside of a car?.

I can't help thinking that a diesel van would be a better fit for what you plan to do.

I think I've posted before about mixed fuel (diesel and LPG) operation, which had a vogue in Australia, and gave improvements in power, emissions and fuel economy.

One might expect it would also make life easier on a DFP, though I believe the peak popularity predated general DPF deployment, so I dont know this for a fact.

Perhaps this could be a niche for CNG, and, since the main fuel source would still be diesel, this would allow use of a smaller, more practically sized gas bottle.

The benefits of mixed fuel operation were claimed for a professional installation, which wasn't cheap. Hare brained bodge-wise, though, my understanding is that "traditional" diesels generally operate with a large excess of air, and power is moderated by adjusting the fuel delivery.

This might imply that you could just run a constant "background" gas bleed, adjusting the power with the diesel injection, without a need for sophisticated stochiometric control,

I do like a good hare brained bodge.

Van owners: LPG is dying, let's talk biomethane! - edlithgow

Good overview of the CNG technical basics as of 2014.

www.autospeed.com/cms/a_113059/article

Climate change, and the associated change in the political climate, doesnt feature, but that is probably more important than any technical limitation these days.

Enthusiastic review of mixed LPG-diesel fuelling system, from 2012

www.autospeed.com/cms/a_113059/article

Edited by edlithgow on 24/03/2024 at 01:53

Van owners: LPG is dying, let's talk biomethane! - edlithgow

There is nothing new in the world of gas powered cars - can't understand why they didn't catch on? gas cars ww2 - Google Search

Wood and town gas-powered tanks and half-tracks, including Tiger I allegedly running on compressed town gas!

tanks-encyclopedia.com/ww2/nazi_germany/gas-powere...p

If thats true, range must have been very very low.

They say

Luckily, Town gas or Stadtgas can be bottled. When mildly compressed it easily changes to a liquid state. This allows a large amount of gas (stored energy) to be contained in a relatively small space. ”

“Mildly compressed” and “easily” are of course imprecise terms, but my understanding is that cryogenic storage for liquid hydrogen has a typical operating pressure of 150 atmospheres, not apparently very consistent with the word “mild”.

At typical ambient temperatures (and, since these were almost certainly NOT cryogenic storage bottles, those are the relevant temperatures), hydrogen can not practically be liquified.

This is why civilian vehicles operating on town gas used big roof ballons.

I don’t know if the carbon monoxide component of the town gas can be liquified, but given the hydrogen content, I assume the gas in these bottles was NOT in liquid form, and thus that the amount stored, and the range, must have been very low.

Van owners: LPG is dying, let's talk biomethane! - bathtub tom

You quote: “Luckily, Town gas or Stadtgas can be bottled. When mildly compressed it easily changes to a liquid state. This allows a large amount of gas (stored energy) to be contained in a relatively small space. "

Then state: hydrogen can not practically be liquified.

and: I don’t know if the carbon monoxide component of the town gas can be liquified, but given the hydrogen content, I assume the gas in these bottles was NOT in liquid form, and thus that the amount stored, and the range, must have been very low.

You appear to be quoting that town gas could easily be compressed, but then stating because of its hydrogen content it can't ????

Van owners: LPG is dying, let's talk biomethane! - Andrew-T

You appear to be quoting that town gas could easily be compressed, but then stating because of its hydrogen content it can't ????

Any gas can be compressed, but no gas can be LIQUEFIED above its Critical Temperature, which is pretty low for hydrogen (can't remember offhand). The point is that any practical container for hydrogen at ambient temperature would have to withstand high pressure - i.e. be very heavy.

Van owners: LPG is dying, let's talk biomethane! - bathtub tom

You quote: “Luckily, Town gas or Stadtgas can be bottled. When mildly compressed it easily changes to a liquid state. This allows a large amount of gas (stored energy) to be contained in a relatively small space. "

Then state: hydrogen can not practically be liquified.

and: I don’t know if the carbon monoxide component of the town gas can be liquified, but given the hydrogen content, I assume the gas in these bottles was NOT in liquid form, and thus that the amount stored, and the range, must have been very low.

You appear to be quoting that town gas could easily be compressed, but then stating because of its hydrogen content it can't ????

Van owners: LPG is dying, let's talk biomethane! - galileo

You quote: “Luckily, Town gas or Stadtgas can be bottled. When mildly compressed it easily changes to a liquid state. This allows a large amount of gas (stored energy) to be contained in a relatively small space. "

Then state: hydrogen can not practically be liquified.

and: I don’t know if the carbon monoxide component of the town gas can be liquified, but given the hydrogen content, I assume the gas in these bottles was NOT in liquid form, and thus that the amount stored, and the range, must have been very low.

You appear to be quoting that town gas could easily be compressed, but then stating because of its hydrogen content it can't ????

No, he said that it can be compressed but NOT liquified, therefore total energy in such a bottle would give a very low range for the vehicle.

Given enough pressure almost everything can be compressed, but gases can not be liquified above their critical temperature.

For carbon monoxide this temperature is -140.3 C, so liquid CO would need to be below this.

For hydrogen it is - 240 C at 191 psi, for methane it is about - 82 C.

,

Van owners: LPG is dying, let's talk biomethane! - edlithgow

You quote: “Luckily, Town gas or Stadtgas can be bottled. When mildly compressed it easily changes to a liquid state. This allows a large amount of gas (stored energy) to be contained in a relatively small space. "

Then state: hydrogen can not practically be liquified.

and: I don’t know if the carbon monoxide component of the town gas can be liquified, but given the hydrogen content, I assume the gas in these bottles was NOT in liquid form, and thus that the amount stored, and the range, must have been very low.

You appear to be quoting that town gas could easily be compressed, but then stating because of its hydrogen content it can't ????

Correct.

Twice

I'm criticising the people I'm quoting. I think they are wrong. (Its the Internyet)

That aside, there are photos of Panther (about 45 tonnes) and Tiger I (about 55 tonnes) tanks with non huge cylinders on their rear decks, which are claimed to contain town gas. These were apparently used for training, with presumably a town gas supply (and compressors) available at the training base, but even so, I was surprised they had a usable range/endurance.

It would be interesting to know what it was

Edited by edlithgow on 20/03/2024 at 12:33

Van owners: LPG is dying, let's talk biomethane! - skidpan

The term "TOWN GAS" was used back before the 70's when North Sea Gas (Natural Gas) came on stream. Town Gas was the stuff made at the local gas works in this country from coal/coke (every town had one) and was stored in the huge gasometers that dominated the skyline. In our town they were in the town centre behind shops, banks etc, crazy place to put them but different times.

The process was not at all environmentally friendly. The gas contained a***nic and to clean this out before it went into peoples houses it was filtered through a chemical that turned deep blue with use (referred to as peacock blue) and was rarely removed from site and created a huge issue when the sites were cleaned up. Cleaning up such sites was a good earner for the company I worked for but we were rarely able to do a total clean. Had to provide systems to prevent ground water passing trough the site and any product coming to the surface, cost a fortune but in inner city areas developers were prepared to pay when land was mega expensive.

So what gas are posters referring to, no Town gas in the UK as far as I know.

Van owners: LPG is dying, let's talk biomethane! - galileo

The term "TOWN GAS" was used back before the 70's when North Sea Gas (Natural Gas) came on stream. Town Gas was the stuff made at the local gas works in this country from coal/coke (every town had one) and was stored in the huge gasometers that dominated the skyline. In our town they were in the town centre behind shops, banks etc, crazy place to put them but different times.

The process was not at all environmentally friendly. The gas contained a***nic and to clean this out before it went into peoples houses it was filtered through a chemical that turned deep blue with use (referred to as peacock blue) and was rarely removed from site and created a huge issue when the sites were cleaned up. Cleaning up such sites was a good earner for the company I worked for but we were rarely able to do a total clean. Had to provide systems to prevent ground water passing trough the site and any product coming to the surface, cost a fortune but in inner city areas developers were prepared to pay when land was mega expensive.

So what gas are posters referring to, no Town gas in the UK as far as I know.

Ed's post is referring to WW2 Germany, when they used the same process as we did to produce town gas from coal.

Years ago I visited Laporte's sulphuric acid works in Castleford, iron oxide was used at gasworks to filter sulphur from the gas: the resulting iron sulphide was burned to give SO2 to feed the lead-chamber acid process.

Van owners: LPG is dying, let's talk biomethane! - edlithgow

When I worked in London there was a large wilderness area out East of Docklands with partially demolished concrete buildings all leaning sideways. Very post apocalypse, but AFAIK only used as a slightly unconvincing Cockney stand-in for Hue, in Kubrick's Full Metal Jacket.

Tempted to compare it to contemporary Gaza, but in fact that appears to have been more thoroughly demolished.

Technology, at least, moves on.

The story was this had been the huge Beckton Gas Works, which they'd started to demolish, but then found it to be so horribly contaminated (dioxin, mostly) that they had to stop.

I did have a bit of a peripheral poke around but didn't explore it thoroughly, which I regret. Eventually, and very slowly, they did clean it up. I suppose the value of the site inflated enough to cover the clean-up costs, plus maybe the decon techniques improved.

Much earlier, when camping in London, I considered pitching a tent on the site of a long-demolished gasworks in Richmond, near Kew, but thought better of it, since you could still smell that gasworks smell. My grandparents lived fairly close to York gasworks so I was familiar with the smell as a child.

I ended up on a tidal desert island in the Thames, probably healthier, though it had a derelict boatyard so maybe not chemically pristine..

Edited by edlithgow on 21/03/2024 at 00:38