wrote:
On Sat, 10 Apr 2021 15:31:50 -0000 (UTC)
Recliner wrote:
wrote:
On Sat, 10 Apr 2021 11:04:28 -0000 (UTC)
Well blue hydrogen is a non starter, but even green hydrogen is far less
efficient in wind turbine to wheel energy terms taking in every stage + the
vehicle itself than simply charging up a battery. Something like 50% for a
battery EV vs 30% for green H2 I remember reading. The only single advantage
H2 has over batteries is recharge time, other than that its hopeless.



Recharge time and capacity. It has a much higher energy density than
current and projected future batteries, unless there's a big step change
(possible at some stage, but not imminent). .

That matters for long distance lorries and buses for whom suitable batteries
would be a ridiculous size, but for cars its not even an issue right now,
never mind as technology advances. Yes, they're maybe half a ton heavier
than an equivalent ICE car at most, but the vehicle size is the same, if
not a bit smaller.

Which is why H2 is mainly being considered for larger, heavier vehicles:
trains, trucks, long distance buses, large SUVs, perhaps even short range
airliners. It's not needed nor viable for ordinary cars.

wrote:
On Sat, 10 Apr 2021 15:16:50 -0000 (UTC)
Sam Wilson wrote:
wrote:
H2 has over batteries is recharge time, other than that its hopeless.

That’s a not inconsiderable advantage!

It is, but otoh once - one hopes - street recharging via some sort of
infrastructure built into street lights or similar for those who don't have
driveways becomes the norm in a decade or 2, that advantage will become
redundant except for the very few people who need to do ultra long journeys
without much in the way of stopping.

The main issue with EVs isn't the battery vs H2 argument , its where the power
is going to come from to power them all in the first place because right now
the generating capacity simply isn't there and short termist politicians
don't seem to be interested in providing it, merely exchanging like for like
with coal and gas gen replaced by wind farms so they can polish their green
halos.

That’s true. Maybe they’re thinking ahead to a time when we might have to
accept a change in lifestyle rather than trying to find “sustainable� ways
to maintain our current ones.

Sam

--
The entity formerly known as
Spit the dummy to reply

On 10/04/2021 16:36, wrote:
On Sat, 10 Apr 2021 15:31:50 -0000 (UTC)
Recliner wrote:
wrote:
On Sat, 10 Apr 2021 11:04:28 -0000 (UTC)
Well blue hydrogen is a non starter, but even green hydrogen is far less
efficient in wind turbine to wheel energy terms taking in every stage + the
vehicle itself than simply charging up a battery. Something like 50% for a
battery EV vs 30% for green H2 I remember reading. The only single advantage
H2 has over batteries is recharge time, other than that its hopeless.



Recharge time and capacity. It has a much higher energy density than
current and projected future batteries, unless there's a big step change
(possible at some stage, but not imminent). .

That matters for long distance lorries and buses for whom suitable batteries
would be a ridiculous size, but for cars its not even an issue right now,
never mind as technology advances. Yes, they're maybe half a ton heavier
than an equivalent ICE car at most, but the vehicle size is the same, if
not a bit smaller.


https://www.bbc.co.uk/news/science-environment-56678669

--
Graeme Wall
This account not read.

Roland Perry wrote:
In message , at 15:32:14 on Sat, 10 Apr
2021, remarked:
On Sat, 10 Apr 2021 15:16:50 -0000 (UTC)
Sam Wilson wrote:
wrote:
H2 has over batteries is recharge time, other than that its hopeless.

That’s a not inconsiderable advantage!

It is, but otoh once - one hopes - street recharging via some sort of
infrastructure built into street lights or similar for those who don't have
driveways becomes the norm in a decade or 2, that advantage will become
redundant except for the very few people who need to do ultra long journeys
without much in the way of stopping.

The main issue with EVs isn't the battery vs H2 argument , its where the power
is going to come from to power them all in the first place because right now
the generating capacity simply isn't there

And nor of course is there much more than 13A ring main linking up the
streetlights in any one street.

and short termist politicians
don't seem to be interested in providing it, merely exchanging like for like
with coal and gas gen replaced by wind farms so they can polish their green
halos.



And even if the street lamp supply is upgraded it doesn’t address the issue
of the local thieves/yobbos cutting and nicking the charge cables or
sticking chewing gum up the works etc. We’ve enough trouble with catalytic
converters going awol as it is. Then you’ll have an entire claims industry
supporting folk who have “tripped� over a cable.

On 10/04/2021 16:57, Graeme Wall wrote:
On 10/04/2021 16:36, wrote:
On Sat, 10 Apr 2021 15:31:50 -0000 (UTC)
Recliner wrote:
wrote:
On Sat, 10 Apr 2021 11:04:28 -0000 (UTC)
Well blue hydrogen is a non starter, but even green hydrogen is far
less
efficient in wind turbine to wheel energy terms taking in every
stage + the
vehicle itself than simply charging up a battery. Something like 50%
for a
battery EV vs 30% for green H2 I remember reading. The only single
advantage
H2 has over batteries is recharge time, other than that its hopeless.



Recharge time and capacity. It has a much higher energy density than
current and projected future batteries, unless there's a big step change
(possible at some stage, but not imminent). .

That matters for long distance lorries and buses for whom suitable
batteries
would be a ridiculous size, but for cars its not even an issue right now,
never mind as technology advances. Yes, they're maybe half a ton heavier
than an equivalent ICE car at most, but the vehicle size is the same, if
not a bit smaller.

https://www.bbc.co.uk/news/science-environment-56678669

[Re yellow lorry image, top] Is the trailer for the batteries?

On 10/04/2021 18:16, Certes wrote:
On 10/04/2021 16:57, Graeme Wall wrote:
On 10/04/2021 16:36, wrote:
On Sat, 10 Apr 2021 15:31:50 -0000 (UTC)
Recliner wrote:
wrote:
On Sat, 10 Apr 2021 11:04:28 -0000 (UTC)
Well blue hydrogen is a non starter, but even green hydrogen is far
less
efficient in wind turbine to wheel energy terms taking in every
stage + the
vehicle itself than simply charging up a battery. Something like
50% for a
battery EV vs 30% for green H2 I remember reading. The only single
advantage
H2 has over batteries is recharge time, other than that its hopeless.



Recharge time and capacity. It has a much higher energy density than
current and projected future batteries, unless there's a big step
change
(possible at some stage, but not imminent). .

That matters for long distance lorries and buses for whom suitable
batteries
would be a ridiculous size, but for cars its not even an issue right
now,
never mind as technology advances. Yes, they're maybe half a ton heavier
than an equivalent ICE car at most, but the vehicle size is the same, if
not a bit smaller.

https://www.bbc.co.uk/news/science-environment-56678669

[Re yellow lorry image, top]Â* Is the trailer for the batteries?

That was my thought!

--
Graeme Wall
This account not read.

On Fri, 09 Apr 2021 20:08:22 -0500, Christopher A. Lee
wrote:

On Fri, 09 Apr 2021 23:50:21 +0100, Charles Ellson
wrote:

On Fri, 09 Apr 2021 08:01:36 -0500, Christopher A. Lee
wrote:

On Thu, 8 Apr 2021 23:20:42 +0100, Roger Lynn
wrote:

On 08/04/2021 13:16, Sam Wilson wrote:
I haven’t noticed it so much recently, but Edinburgh used to have quite a
lot of dedicated buses with the route number included in the livery as well
as on the indicator blinds.

Stagecoach do that a lot (at least in some areas). At weekends it's common
to see buses on the wrong routes.

Back when it was still all London Transport, did red buses ever appear
on green (country) routes or vice versa, where the two systems
overlapped?

They used to turn up if there wasn't one of the right colour available
due to accidents, overhauls etc. although RLH low height buses seemed
to never get a repaint from green when permanently transferred to the
230 route around Harrow.

The RLH buses I remember on the 230 were all red. I grew up in Harrow
and don't remember seeing any in green.

Not often and mainly in the last few years before it mutated into the
H1. There wasn't usually more than one at a time.
There are some photographs of RLH27, e.g.
https://www.flickr.com/photos/megaanorak/8590545356
but the trouble with that bus IIRC is that by the time the 230 ceased
it had already gone into private ownership and some photographs of it
on the 230 are actually of it driving around the route on the first
day of the new route taking over.

wrote:
On Sat, 10 Apr 2021 15:16:50 -0000 (UTC)
Sam Wilson wrote:
wrote:
H2 has over batteries is recharge time, other than that its hopeless.

That’s a not inconsiderable advantage!

It is, but otoh once - one hopes - street recharging via some sort of
infrastructure built into street lights or similar for those who don't have
driveways becomes the norm in a decade or 2, that advantage will become
redundant except for the very few people who need to do ultra long journeys
without much in the way of stopping.



I thought we were talking about buses, particularly long-distance coaches
eg National Express. The battery will have to be enough to last a whole day
(plus reserve). H2 would definitely have an advantage there.


Anna Noyd-Dryver

Roland Perry wrote:
In message , at 15:32:14 on Sat, 10 Apr
2021, remarked:
On Sat, 10 Apr 2021 15:16:50 -0000 (UTC)
Sam Wilson wrote:
wrote:
H2 has over batteries is recharge time, other than that its hopeless.

That’s a not inconsiderable advantage!

It is, but otoh once - one hopes - street recharging via some sort of
infrastructure built into street lights or similar for those who don't have
driveways becomes the norm in a decade or 2, that advantage will become
redundant except for the very few people who need to do ultra long journeys
without much in the way of stopping.

The main issue with EVs isn't the battery vs H2 argument , its where the power
is going to come from to power them all in the first place because right now
the generating capacity simply isn't there

And nor of course is there much more than 13A ring main linking up the
streetlights in any one street.



Streets and pavements are dug up often enough for other reasons, that doing
it again to upgrade the wiring/install a parallel circuit, isn't the end of
the world.


Anna Noyd-Dryver

On 10/04/2021 20:36, Anna Noyd-Dryver wrote:
Roland Perry wrote:
In message , at 15:32:14 on Sat, 10 Apr
2021, remarked:
On Sat, 10 Apr 2021 15:16:50 -0000 (UTC)
Sam Wilson wrote:
wrote:
H2 has over batteries is recharge time, other than that its hopeless.

That’s a not inconsiderable advantage!

It is, but otoh once - one hopes - street recharging via some sort of
infrastructure built into street lights or similar for those who don't have
driveways becomes the norm in a decade or 2, that advantage will become
redundant except for the very few people who need to do ultra long journeys
without much in the way of stopping.

The main issue with EVs isn't the battery vs H2 argument , its where the power
is going to come from to power them all in the first place because right now
the generating capacity simply isn't there

And nor of course is there much more than 13A ring main linking up the
streetlights in any one street.



Streets and pavements are dug up often enough for other reasons, that doing
it again to upgrade the wiring/install a parallel circuit, isn't the end of
the world.


Even assuming you can distribute enough power to make them function,
there aren't enough lamposts available for all the people who are likely
to want to use them.

--
Graeme Wall
This account not read.