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“Battery EV” vs “Hydrogen Fuel cell EV”

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TimFox:
Hydrogen and methane are both inflammable:  what is important to investigate is the range of gas:oxygen for an inflammable mixture.  Pure gas (hydrogen or methane) will not burn, and too high an oxygen content will not support combustion:  there is a large range in between that is hazardous.
(I am using the literal meaning of "inflammable", not the Underwriters' preferred usage of "flammable".)

TimFox:

--- Quote from: tom66 on November 15, 2021, 10:37:54 pm ---
--- Quote from: SiliconWizard on November 15, 2021, 10:34:22 pm ---Regarding distributing hydrogen safely through pipelines, wouldn't that require major modifications to the existing ones anyway to reach any reasonable level of safety? Really wondering.

--- End quote ---

What, so natural gas is a totally safe and non-explosive gas? 

One issue is existing pipelines need to be replaced if they contain certain steel, as the steel is embrittled by hydrogen.

Many of these pipelines have been replaced with plastic/composite pipes already anyway.  They are cheaper to install, more flexible, and last longer.

A secondary issue is how you maintain a dual-fuel natural gas and hydrogen grid, without running two sets of pipes.  Some infrastructure won't cope with hydrogen, but others might require pure hydrogen.  I wonder how practical mass-separating the gases would be.

--- End quote ---

From an industrial website: (referrring to hydrogen embrittlement at room temperature).  https://www.imetllc.com/hydrogen-embrittlement-steel/
"High-strength steels with tensile strength greater than about 145 ksi (1000 MPa) are the alloys most vulnerable to hydrogen embrittlement."
"For applications where there will be hydrogen absorption while a component is in service, the use of lower strength steels and reduction of residual and applied stress are ways to avoid fracture due to hydrogen embrittlement."

About 20 years ago, the local natural gas utility put a plastic pipe inside the original steel gas pipe from the gas main to my house gas meter.  However, most of my gas piping inside is steel, with some copper.  Hydrogen embrittlement is also a concern with steam attacking iron, and was a limit to the superheated steam temperature in steam locomotives.

nctnico:

--- Quote from: tom66 on November 15, 2021, 10:32:33 pm ---
--- Quote from: nctnico on November 15, 2021, 09:12:51 pm ---Tesla's superchargers aren't along the highway. Look at the prices from -for example- Ionity: 0.79 euro per kWh

--- End quote ---

Ionity's high pricing is very deliberate to keep their walled garden but since they have CCS they still attract EU funding/subsidies (stupid move by the EU to not cap the rates they charge at.)

If you have a VW subscription it's ~£14/m and then £0.25/kWh.
With Hyundai it's ~£11/m then £0.28/kWh.
Mercedes throw 3 years in free subscription with the car, energy @ £0.25/kWh.

(None of these 'passes' are available if you do not own one of the respective vehicles.  No idea if/how the charging station validates that it is 'that' particular car though.)

And I suppose this isn't surprising given Ionity is majority owned by VW, Hyundai, Daimler, Ford & BMW.

It's very clearly built with the intention of making Tesla and non-Ionity "supported" EVs expensive to charge.  It'll be interesting to see how this shifts as Tesla are charging at their superchargers about the same rate, but all car manufacturers get the same rate.

--- End quote ---
That is another problem that needs to be hashed out first: fair rates for charging. At this point nobody knows for how long the charging infrastructure that is being build now is relevant. Given the rapid progress of battery and charging technology it would be foolish to think that is longer than 10 years so any investment needs to be earned back before that. With fast chargers you can choose between several competitors but with street level charging you are basically stuck with whatever company wins the bid for your street. Currently none of the companies that are building EV charging infrastructure are making a profit. That has to change at some point so I expect prices for charging to rise significantly.

And it is nothing new. For example: where I live there is district heating so I'm stuck with whatever company owns the heating infrastructure. It has taken 30 years to have a law passed that sets limits to the tarifs of district heating. I used to pay 35 euro per GJ. Since the law is in effect I pay 25 euro per GJ.


--- Quote from: SiliconWizard on November 15, 2021, 10:34:22 pm ---Regarding distributing hydrogen safely through pipelines, wouldn't that require major modifications to the existing ones anyway to reach any reasonable level of safety? Really wondering.

--- End quote ---
Gas is gas. Most of the natural gas infrastructure in the NL seems to be suitable for hydrogen.

richard.cs:

--- Quote from: tom66 on November 15, 2021, 10:37:54 pm ---What, so natural gas is a totally safe and non-explosive gas?

--- End quote ---

In comparison to hydrogen, yes. Methane in air is explosive from 5% to 17%, hydrogen 4% to 75%. In practice it means hydrogen is much more likely to make an explosive mix, even before you account for its greater tenancy to leak in the first place due to the small molecule.

tom66:

--- Quote from: nctnico on November 15, 2021, 10:46:44 pm ---That is another problem that needs to be hashed out first: fair rates for charging. At this point nobody knows for how long the charging infrastructure that is being build now is relevant. Given the rapid progress of battery and charging technology it would be foolish to think that is longer than 10 years so any investment needs to be earned back before that. With fast chargers you can choose between several competitors but with street level charging you are basically stuck with whatever company wins the bid for your street. Currently none of the companies that are building EV charging infrastructure are making a profit. That has to change at some point so I expect prices for charging to rise significantly.

And it is nothing new. For example: where I live there is district heating so I'm stuck with whatever company owns the heating infrastructure. It has taken 30 years to have a law passed that sets limits to the tarifs of district heating. I used to pay 35 euro per GJ. Since the law is in effect I pay 25 euro per GJ.
--- End quote ---

Well, it's a good reason that domestic charging has to be at a fair rate, for sure.  Actually, it would be best if the chargers are like electricity to your home.  They should have smart metering built in, but they form part of your energy bill at home. So you can still take advantage of discount electricity at night.  And choose different providers.

On the road, I would argue the competitive market is enough to keep rates fair, petrol station prices are generally competitive.  The average retailer makes a few pence per litre off fuel, they hope you come in and buy a sandwich and drink instead because that makes them more than 50 litres of fuel does.  Motorway services always more expensive but if you are prepared to go off the motorway for a mile or two you can save a small fortune.  I doubt that EV chargers will be any different.

Regarding profit, I am not sure that is fair.  IONITY is having a massive chunk bitten out of it by vulture capitalists.  BP own "bp pulse" (a useless, unreliable network, FWIW, but that's another matter).  The money is there and there's no reason EV charging can't be profitable but Amazon and Tesla took decades before they made a penny...

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