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The 100D spent the night nervously contemplating which fuel is smarter (hoping the smokers in the car park didn't get any closer) - then set course for Edinburgh.

Be nice if these places provided a fueling facility for real zero emissions vehicles with your tax money, rather than unicorns.

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I am in the Hilton Garden Inn this week and was also looking at the very unused H2 station with its 'no trespassing' signs. The age of hydrogen is still far off...
 

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What are all those red cylinders on pallets at the back of the station? Surely not cylinders of gas?
 

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I am in the Hilton Garden Inn this week and was also looking at the very unused H2 station with its 'no trespassing' signs. The age of hydrogen is still far off...
Ah - maybe we passed each other in the lobby.

What are all those red cylinders on pallets at the back of the station? Surely not cylinders of gas?
Yep - they truck it in. Supporting a Growing UK Hydrogen Infrastructure: Air Products’ High Pressure Tube Trailer Fleet Expansion and Permanent Fuelling Station Installation
 

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Oh, and it can run out if too many refuel at once.
Yes. And following that link @dpeilow posted above, Air Products boasts that their 'Tube Trailer' has the H2 at 500bar pressure - up from 200bar previously, but still lower than the 700bar that the various cars are using to claim their max range.

So if you think those red cylinders in the photo are a little bigger than the tank in a car (to reflect the 500/700 bar difference), then it can only refuel 96 cars (from empty) before needing a new delivery. Even if you think those cylinders are more than double the size of one in a car, it's only 200 cars. Compare to a petrol tanker with 38,000 litres capacity and a car with a 60 litre tank = 760 cars per tanker load.

I can't find anything on AirProducts own site to clarify the trailer capacity; this third-party report talks about a similar trailer with 400kg H2 capacity at 200bar (of which only 85% can actually be emptied), so that would give 68 refills of a 5kg Toyota Mirai. So that seems to match with the newer 500bar trailers giving something in the region 100-200 fills.

However, AirProducts literature implies that this isn't a serious solution for high volume users; instead you should have cryogenic hydrogen delivered with various plant to then process that for delivery into vehicles. The stuff for hydrogen forklifts looks rather more well developed than that for road vehicles.

So on the one hand we can't legitimately criticize the parameters of these initial H2 stations, as they are just the equivalent of a shop with a few jerry cans of petrol, but on the other hand anyone who says "look! the infrastructure for H2 cars is already starting to be built" is talking nonsense - these initial "investments" are just throw-away demo units.
 

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Absolutely. In fact these stations pump a small buffer tank up to 800 bar in order to bring the car's tank up to 700 bar without the equilisation of pressure reducing the flow down to nothing. If that buffer tank is empty and you are last in the queue, prepare to wait.

And as you say, they are a stop-gap solution. As are the sites powered by renewables, which as we showed before cannot realistically supply more than a handful of cars per day.
 

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Did you follow this itinerary or go off piste?

Personally I'd probably have gone straight to Charnock Richard (can't be much more than 200 miles which is childs play in a 100D) and then either done a single long stop there, or split into two short stops one at Charnock and then one at Abington.

But by Tesla Nav standards it's certainly not a silly suggestion, which makes a nice change!
 

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Did you follow this itinerary or go off piste?
That was a hypothetical "what if" sat-nav plot to see what would be needed to drive from that hydrogen station to Edinburgh. Actually I had to go to work :(

However it did give me an idea that perhaps we should get a convoy of Teslas and do such a point-to-point trip to another hydrogen station up north, just for a giggle.

As I was staying in that hotel overnight (and as it doesn't have a charging point) I started the trip with about 75%, having driven up from Winchester. This is why the nav was plotting a route with a quick stop at Warwick.

I tried the same again this morning from home, having done a full charge last night, and this time it went straight to Charnock Richard. However, I was giving it the beans on the way up the A34 to work and several times the nav warned that I needed to slow down in order to make it to the charge point. That seems strange as it could have dynamically re-plotted the course to call in at Warwick as well but obviously they haven't thought of that yet.

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That was a hypothetical "what if" sat-nav plot to see what would be needed to drive from that hydrogen station to Edinburgh. Actually I had to go to work :(

However it did give me an idea that perhaps we should get a convoy of Teslas and do such a point-to-point trip to another hydrogen station up north, just for a giggle.

As I was staying in that hotel overnight (and as it doesn't have a charging point) I started the trip with about 75%, having driven up from Winchester. This is why the nav was plotting a route with a quick stop at Warwick.

I tried the same again this morning from home, having done a full charge last night, and this time it went straight to Charnock Richard. However, I was giving it the beans on the way up the A34 to work and several times the nav warned that I needed to slow down in order to make it to the charge point. That seems strange as it could have dynamically re-plotted the course to call in at Warwick as well but obviously they haven't thought of that yet.

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Very impressed that it actually suggested a 1-stop strategy for the trip - historically it was much too cautious (as a result of which I never use it). Though equally the 100D does make its job rather easier...

The yellow "keep below xx" messages are also cautious. I think they trigger whenever the car thinks you'll arrive at your destination with less than MIN(7%, current SOC * 0.1). On long trips to well-known destinations I generally have a yellow warning message of some kind showing for most of the journey :oops:

Amusingly they frequently differ between the two screens - it's quite common to see "stay below 65mph" on the centre display at the same time as "stay below 60mph" on the instrument cluster...
 

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Discussion Starter #17
According to Zap Map, that Heathrow hydrogen station is reported offline for the last couple of months, so might explain the lack of traffic to it.

Looks like two others are offline for a while too. Must be a pain if you lease one of these cars in, say, Nottingham.

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I looked a bit more into those cylinders at the back of the site. 120 in total and I recon they are K sized ones, as per here High Purity Hydrogen Cylinder | BOC Shop

The data sheet says each contains 7.21 m^3 of hydrogen. I presume that means at STP, which would therefore weigh 648 grammes.

The data sheet also says each cylinder has 65 kg gross weight. Therefore the ratio of total weight to contained gas is virtually 100:1 (this does not account for the residual gas that will not come out when depleted, so in reality is a bit worse).

120 cylinders contain 77.76 kg of gas, which is enough to fill 15 cars.


Furthermore, each cyclinder costs £39.17 exc delivery from BOC. It needs 8 to fill a car with a 5kg tank = £313.36 total.
 

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That datasheet has a max pressure of 175, so not exactly the same.

Using this source of a graph of hydrogen density vs pressure (first one I found and it looks vaguely plausible):

Outer dimensions of the cylinder are 1460x230, so volume 1.46*.115*.115*pi = 0.0607; call the inner volume 0.06 to be generous. At 175 bar it's about 12kg/m^3, so the cylinder holds .72kg - very close to your calculation, specially as I've overestimated the contained volume. At 500bar it's about 31kg/m^3, so 1.86kg per cylinder; 120 cylinders = 223kg = 44 cars. At 700 bar (imagining one of those cylinders being the tank in a car) it's 40kg/m^3, so each cylinder holds 2.4kg.

I think the cylinders on the pallets must be a bit bigger than these. Presumably the pallets are meant to fill the back of a typical lorry (max 2.55m wide), so we'd expect more like 2m long rather than 1.46m.

Going at it another way, max size lorry is 12m long 2.55m wide; assume you're prepared to go 2m above loadbed height so total volume is 12*2.5*2=60m^3. Assume a set of cylinders gives 50% useful volume after accounting for the gaps between cylinders, so 30m^3 of gas; at 500 bar =930kg = 186 fills of a car. Probably these ones aren't quite so tall, but this gives a feel for the best you could manage on a standard delivery lorry and again it's coming out to similar numbers.

I'm also not sure how the cylinder gets to weigh as much as 65kg if it's a lightweight composite structure; maybe BOC's ones have a steel outer skin or something? But certainly the delivery lorry is going to weigh about the same whether full or empty.
 

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Discussion Starter #20
Air Products PR states that this site gets deliveries from a hydrogen tube trailer which delivers hydrogen at 500 bar.

Supporting a Growing UK Hydrogen Infrastructure: Air Products’ High Pressure Tube Trailer Fleet Expansion and Permanent Fuelling Station Installation

Looking up details about this tube trailer I found this

Air Products launches hydrogen high-pressure tube trailers for European hydrogen infrastructure deployment - Renewable Energy Focus



Air Products launches hydrogen high-pressure tube trailers for European hydrogen infrastructure deployment - Renewable Energy Focus



http://photolibrary.airproducts.com/ImageViewer.aspx?uid=46B5F260167747CDA1D8150CAABC42BA&m=9


However this looks nothing like the cylinders in the compound on site. Do they transfer from this into the cylinders or have they given up on it and just bring in the old style ones?


Also:

“Munich, 25 September 2013 – Technology company The Linde Group has developed a new storage technology that will enable a much more efficient transport of larger amounts of hydrogen. The new solution works at a higher pressure of 500 bar (7,250 psi) and uses new, lighter storage materials to more than double the amount of compressed gaseous hydrogen (CGH2) that can be transported in a single truck load……
Each trailer features 100 lightweight composite storage elements developed in collaboration with xperion Energy & Environment GmbH. A single trailer can transport over 1,100 kilograms, or 13,000 normal cubic metres, of hydrogen gas. In addition, the trailers can now be filled and emptied in less than 60 minutes.”
 
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