Hydrogen

[Michael GilliganParticipant @michaelgilligan61133]

UPDATE :

**LINK**

https://arstechnica.com/tech-policy/2021/08/ex-lobbyist-slams-blue-hydrogen-says-it-would-lock-in-fossil-fuel-dependence/

MichaelG.

[pgk pgkParticipant @pgkpgk17461]

The claims that Blue Hydrogen will be associated with carbon capture are probably the usual greenwashing. Equally, lobbyists changing sides is probably more with where their allegiance has been bought than any true belief.
Reality is that we have huge numbers of diesel lorries on UK roads (with current worries about a lack of drivers) and at least blue hydrogen would move pollution out of cities.
As for the dangers of hydrogen explosions and fires – remember Buncefield?
https://en.wikipedia.org/wiki/Buncefield_fire

[Clive SteerParticipant @clivesteer55943]

Internal combustion engines, although better than the steam engines that they superseded, are still appallingly inefficient and even a modest improvement would reduce fuel usage and pollution. So whether fuelled by petrol or hydrogen the issue is rather academic.

However electric traction, as demonstrated by very early transport showed excellent environmental benefits but until recently this has been a non-runner for personal transport which we can't seem to live without. If battery technology can be improved according to Moore's law then the future looks better. However there are issues with the "refuelling" of electric cars if provided by our current power distribution network as a huge amount of energy can be easily transported by a fuel tanker. When motor vehicles first came on the scene one refuelled at the chemist but the quite quickly the arrangement evolved and adapted and so it is likely to do for electric cars etc.

The main theme for future energy generation and usage must be towards better efficiency and not necessarily towards reduction although that might be a good this in the short term.

Although climate change is an important issue to be tackled the world population may be the largest Sword of Damocles that we face. As David Attenborough said "in his lifetime the worlds population had tripled" and I'm sure our consumption of the worlds resources to lift our standard of living has followed a similar curve which doesn't bode well for the future.

The meek might end up inheriting the earth and not have to pay the taxes as our "civilised" society may have self destructed. Hopefully the human race won't be stupid enough to let it get that far.

I have a picture in my head of Jeremy Clarkson using the last gallon of petrol in the world to show how fast he can drive around the test track at Dunsfold !

Clive

[pgk pgkParticipant @pgkpgk17461]

Hydrogen combustion may be wasteful, but hydrogen fuel cells use 25% less energy albeit the costs and resources of the fuel cell.

pgk

[Robert Atkinson 2Participant @robertatkinson2]

One issue with fuel cells is the amount of heat that they produce. As a guide for evey kW of electricity produced they generate another kW of heat that has to be delt with. To make it worse the current leading cell technology, PEM, runs at low temperatures. Getting rid of heat with low temperature differentials is difficult. The result is most current designs top out at about 100kW.

Robert G8RPI.

[Paul KempParticipant @paulkemp46892]

Posted by Robert Atkinson 2 on 22/08/2021 12:18:25:

One issue with fuel cells is the amount of heat that they produce. As a guide for evey kW of electricity produced they generate another kW of heat that has to be delt with. To make it worse the current leading cell technology, PEM, runs at low temperatures. Getting rid of heat with low temperature differentials is difficult. The result is most current designs top out at about 100kW.

Robert G8RPI.

Modular and scalable 200kW to mW.

https://www.ballard.com/fuel-cell-solutions/fuel-cell-power-products/marine-modules Other makes available!

Allegedly over 60% efficiency which whilst not ideal is almost twice as efficient as a diesel. Biggest problem with fuel cells is they do not react well to transient loads and they have a relatively slow ramp up to full power, hence requiring a battery bank to even out the load. Interestingly they have a service life somewhere akin to the heavy overhaul interval of a large diesel and with the on cost of battery renewal that skews the lower maintenance cost argument and if you bolt on to that the difference in fuel cost between h2 (whatever colour you want to choose) and marine fuel your container costs will increase! How that compares to current ten fold rise over 2 years is not clear because that is driven by other reasons.

Paul.

[Robert Atkinson 2Participant @robertatkinson2]

Posted by Paul Kemp on 22/08/2021 14:15:33:

Posted by Robert Atkinson 2 on 22/08/2021 12:18:25:

One issue with fuel cells is the amount of heat that they produce. As a guide for evey kW of electricity produced they generate another kW of heat that has to be delt with. To make it worse the current leading cell technology, PEM, runs at low temperatures. Getting rid of heat with low temperature differentials is difficult. The result is most current designs top out at about 100kW.

Robert G8RPI.

Modular and scalable 200kW to mW.

https://www.ballard.com/fuel-cell-solutions/fuel-cell-power-products/marine-modules Other makes available!

Allegedly over 60% efficiency which whilst not ideal is almost twice as efficient as a diesel. Biggest problem with fuel cells is they do not react well to transient loads and they have a relatively slow ramp up to full power, hence requiring a battery bank to even out the load. Interestingly they have a service life somewhere akin to the heavy overhaul interval of a large diesel and with the on cost of battery renewal that skews the lower maintenance cost argument and if you bolt on to that the difference in fuel cost between h2 (whatever colour you want to choose) and marine fuel your container costs will increase! How that compares to current ten fold rise over 2 years is not clear because that is driven by other reasons.

Paul.

Those are marine units. The one mobile application where there is a readily available heat sink, the ocean.
Cars, planes and trucks are another matter.

[Paul KempParticipant @paulkemp46892]

I did refer to marine several times but it's not an insurmountable problem for vehicles and aircraft benefit from significantly lower air temperatures than at ground level. Toyota have done it for vehicles (in development) and there are others working towards it too. Whether it's a good idea or not is a different debate.

Paul.

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