camelot-forum.co.uk

https://fleetworld.co.uk/mod-trials-hyd ... -ev-fleet/

I mean, aside from the fact that the Skoda Superb PHEV pictured (range of 30 miles on a very good day) has a max charge rate of 3.6 kW, why not just plug it in to a charge point connected to the grid? Or even just a regular 13A socket. It would avoid:

Water Electrolysis
Hydrogen Purification
Hydrogen Compression
Cylinder Filling
Cylinder Transportation
Cylinder Storage and Distribution
Hydrogen Decompression
Fuel Cell Power Generation
Power Conditioning
Supply to the charging point
Cylinder Return and Refilling
(and probably a load of other stuff I've missed too)

Never mind the cost and complete waste of precious green hydrogen that could be used to decarobonise industrial process instead?

Yes, you can charge a plug-in hybrid using electricity produced by green hydrogen-powered generators? But they seem to have forgotten the "just because you could, dooesn't mean you should" phrase from Jurassic Park...

Anyone?

Cant help but agree - why not just tack a few panels on the roofs and charge for free from those?

Personally id sooner see the money spent on a few bullets or an extra squaddie or two.

Next they will be trying to create an EV powered tank or something. Hold on mr Putin/Kim etc, dont invade just yet im still charging my battleship, come back tomorrow!

Nowt like officialdom to waste other peoples money.

Also loving the irony of the camo clad squaddie with a hi vi vest on lol

Some twonk in camo and a hi viz vest? Where's the self respect?

"Air Vice-Marshal Rich Pratley, the MOD’s senior responsible owner for this project, said"

Oh just f**k off Dick, u and your hi viz.

Dan, thank you for bringing this to out attention.

dan_b wrote: ↑Tue Sep 10, 2024 6:08 pm https://fleetworld.co.uk/mod-trials-hyd ... -ev-fleet/

I mean, aside from the fact that the Skoda Superb PHEV pictured (range of 30 miles on a very good day) has a max charge rate of 3.6 kW, why not just plug it in to a charge point connected to the grid? Or even just a regular 13A socket. It would avoid:

Water Electrolysis
Hydrogen Purification
Hydrogen Compression
Cylinder Filling
Cylinder Transportation
Cylinder Storage and Distribution
Hydrogen Decompression
Fuel Cell Power Generation
Power Conditioning
Supply to the charging point
Cylinder Return and Refilling
(and probably a load of other stuff I've missed too)

Never mind the cost and complete waste of precious green hydrogen that could be used to decarobonise industrial process instead?

Yes, you can charge a plug-in hybrid using electricity produced by green hydrogen-powered generators? But they seem to have forgotten the "just because you could, dooesn't mean you should" phrase from Jurassic Park...

Anyone?

I know what you mean, but I assume the planned end use is in operational conditions, at all hours of day and night, to charge some kind of EV - maybe solar PV / battery would be better in most cases, but maybe not always practical / available (not sure how they ensure a steady delivery of hydrogen to keep producing the electricity)
Although I do think they are overselling it somewhat!

If you've been watching "Downey's Dream Cars" on Quest/Discovery (Robert Downey Junior's attempts to 'green' his extensive car collection a bit) you'd have seen a piece where the US army were showing off their specialist EVs. The army bloke said that supplying fuel 'in the field' was often a challenge but I'd have thought that hydrogen would be way worse than petrol for that! Maybe they're planning to plug their vehicles into the local grid or something...

Yeah I wondered if the “refuelling an EV in the battlefield” was the thinking behind this - but compressed hydrogen is known for being quite explodey- I would imagine an even worse issue for battlefield logistics than diesel?!

dan_b wrote: ↑Wed Sep 11, 2024 10:41 am Yeah I wondered if the “refuelling an EV in the battlefield” was the thinking behind this - but compressed hydrogen is known for being quite explodey- I would imagine an even worse issue for battlefield logistics than diesel?!

Maybe they are thinking that most use comes in training/adin/peace keeping/disaster aid etc. where the result from hostile action is likely very much lower and as such H2 would be acceptable from a danger pov. How much electric energy can you get out of H2 into a car battery via a fuel call compared to a diesel generator? Just wonderig how a tanker of H2 comares to a tanker of diesel when used to charge batteries.

Imagine a 747. Fully fuelled it can fly 400 people across the Atlantic.

If powered by H2, the extra space required for the H2 tanks would fill the entire volume of the plane’s fuselage as well as the existing fuel tanks. Leaving little room for passengers and cargo. That’s how not-energy-dense H2 is compared to Kerosene/ diesel

Countrypaul wrote: ↑Wed Sep 11, 2024 11:00 am

dan_b wrote: ↑Wed Sep 11, 2024 10:41 am Yeah I wondered if the “refuelling an EV in the battlefield” was the thinking behind this - but compressed hydrogen is known for being quite explodey- I would imagine an even worse issue for battlefield logistics than diesel?!

Maybe they are thinking that most use comes in training/adin/peace keeping/disaster aid etc. where the result from hostile action is likely very much lower and as such H2 would be acceptable from a danger pov. How much electric energy can you get out of H2 into a car battery via a fuel call compared to a diesel generator? Just wonderig how a tanker of H2 comares to a tanker of diesel when used to charge batteries.

https://www.idealhy.eu/index.php?page=lh2_outline

H2 has a very high energy density per kg.

But absolutely woeful volumetric energy density.

Hydrogen is an excellent energy carrier with respect to weight. 1 kg of hydrogen contains 33.33 kWh of usable energy, whereas petrol and diesel only hold about 12 kWh/kg (see www.h2data.de).

In terms of volumetric energy density however, hydrogen is outperformed by liquid fuels. This poses a challenge when hydrogen must be transported from the place of its generation to a refuelling station.

Petrol and diesel carry around 8.8 and 10 kWh/litre, respectively.

Under ambient conditions, a cubic metre of hydrogen provides some 3 kWh, equivalent to 0.003 kWh per litre. Pressurised hydrogen contains about 0.5 kWh/litre at 200 bar, 1.1 kWh/litre at 500 bar and 1.4 kWh/litre at 700 bar.

I'm baffled Dan. It seems to me that the H2 is being used purely as a storage means? So why not a big battery instead for the necessary buffer.

Regarding fuel at FOB's (forward operating bases), I recall the US saying that a gallon of diesel costs about $400 delivered. You not only need the tanker truck, but the escort vehicles, air cover, and all the labour/soldier costs. In fact, that was the argument for solar panels at FOB's, to massively reduce the cost and problems of maintaining leccy power.

I'm open to the possibility that at some sites (not necessarily military), you may have a lot of RE generation, and H2 tanks may be a cheaper and simpler way to store a lot of the leccy, but let's start with batts, before we jump to the LDES (long duration energy storage) issue. And I doubt this scenario relates to any military bases - even if they have RE on site, they will most likely be able to export some excess too.

Yep, still baffled!