Motoring Discussion > Hydrogen Miscellaneous
Thread Author: Bobby Replies: 8

 Hydrogen - Bobby
One of Harry Metcalfe’s latest videos is with JCB discussing their focus on Hydrogen vehicles. Wonder what the panels thoughts are on this? Will we go full electric or will we branch out into Hydrogen cells long before full electric is a possibility? Why are car manufacturers all seemingly obsessed with electric only?

Was also interesting to hear Bamford complain that the Govt weren’t listening to him on this!!! But I’m sure he still gets value for money from his Boris donations……

youtu.be/jxtxZY45RMM
 Hydrogen - sooty123
Not seen the video or heard of that presenter but my understanding with hydrogen's main negative is you need vast amounts of electricity to produce it.
 Hydrogen - Manatee
Electricity to hydrogen by electrolysis is about 75% efficient. Then the fuel cell conversion back to electric is about 50% efficient, so c. 35% overall.

Sounds a challenge vs. charging batteries.
 Hydrogen - Lygonos
>>Electricity to hydrogen by electrolysis is about 75% efficient. Then the fuel cell conversion back to electric is about 50% efficient, so c. 35% overall.

Then add in the energy cost to compress it to 600 bar or so, and then transport it around and store it in facilities that require a lot more regulating than liquid hydrocarbons.
 Hydrogen - Zero
It takes about *50 kwh to produce 1kg of Hydrogen,
Car tanks have about 5-6kg of hydrogen for a range of about 400 miles.
a 60kwh EV will do about 350 miles.

Either way we are going to be using a lot of kwh if we wish the same level of automotive mobility.


*varies +/- 10% depending on who you ask.
Last edited by: Zero on Mon 13 Mar 23 at 17:33
 Hydrogen - sooty123
I had a quick skim through the video there was quite a bit on the tractor engine, not much on how you make hydrogen though.
I think JCB are investing in hydrogen producing plants, whether they can scale it up or not I don't know. It may play a role for ships, trains and trucks.
 Hydrogen - Terry
For large machines such as HGVs, combine harvesters, road building equipment etc, fuel use can be between 5 and 25 litres per hour.

A litre of diesel has the equivalent of ~10kwh. Even a low level of consumption would require 50kwh battery for each hour of operation.

As this sort of kit works 7-10 hours per day the size and cost of batteries would be material. Stopping to recharge during the working day would be inefficient, particularly if high capacity recharge points were not available nearby (as may be the case with roadbuilding).

The JCB rationale for hydrogen power may be understandable to comfortably cope with a single days work where electric may be logistically and financially problematic.

Contrast with normal cars where a typical range of 200-300 miles on a full charge would (for most) cover a weeks usage.
 Hydrogen - RichardW
>> A litre of diesel has the equivalent of ~10kwh. Even a low level of consumption
>> would require 50kwh battery for each hour of operation.

It does, but only about 35-40% produces useful work, the rest is lost as heat, so you need less batteries. But it's still a silly idea. So is Hydrogen!
 Hydrogen - Shiny
While hydrogen is not a drop in fuel, it would not take much to modify production over to it, compared to battery power. I think all being well we will just see petrol and diesel replaced with new fuels called e-fuels - (electro-fuels).
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