On Tue, 20 Dec 2011 11:03:50 +0000
Roland Perry wrote:
In message , at 09:40:48 on Tue, 20 Dec
2011, d remarked:
I suspect like most hybrids the battery on its own can't power the vehicle for
more than a few miles so I can't believe that the system can't power the
vehicle on the generator alone. I suspect a fault.

It seems it's the other way round. The generator isn't capable of
powering the bus if the bus is motoring 100% of the time. It's in effect
a generator topping up the battery, which is also receives regen braking
charge. So the battery [alone] is powering the bus, but the whole system
will gradually run out of 'steam' if used too intensively.

These are the compromises required to get the outstanding mpg.

180hp is enough to power a double decker albeit slowly. And since its
unlikely that the battery could be charged faster than any charge would
be taken from it then any power the generator is creating will be going
to the motors - with losses via the battery - anyway. So even if after all
that only say 100hp makes it to the motors it still shouldn't grind to a
halt at the side of the road.

B2003

In message , at 11:15:10 on Tue, 20 Dec
2011, d remarked:
I suspect like most hybrids the battery on its own can't power the vehicle for
more than a few miles so I can't believe that the system can't power the
vehicle on the generator alone. I suspect a fault.

It seems it's the other way round. The generator isn't capable of
powering the bus if the bus is motoring 100% of the time. It's in effect
a generator topping up the battery, which is also receives regen braking
charge. So the battery [alone] is powering the bus, but the whole system
will gradually run out of 'steam' if used too intensively.

These are the compromises required to get the outstanding mpg.

180hp is enough to power a double decker albeit slowly.

And the bus in question was driving fast up the motorway, therefore a
net drain on the battery.

And since its unlikely that the battery could be charged faster than
any charge would be taken from it then any power the generator is
creating will be going to the motors - with losses via the battery -
anyway. So even if after all that only say 100hp makes it to the motors
it still shouldn't grind to a halt at the side of the road.

But it's run out of diesel, dear Liza, dear Liza.
--
Roland Perry

On Tue, 20 Dec 2011 13:01:49 +0000
Roland Perry wrote:
net drain on the battery.

Isn't it limited to 50mph anyway? I'd be surprised if 180hp couldn't manage
that.

But it's run out of diesel, dear Liza, dear Liza.

I thought we were talking in the general sense now, not that specific bus.

B2003

In message , at 13:51:06 on Tue, 20 Dec
2011, d remarked:
net drain on the battery.

Isn't it limited to 50mph anyway? I'd be surprised if 180hp couldn't manage
that.

You seem easily surprised.

But it's run out of diesel, dear Liza, dear Liza.

I thought we were talking in the general sense now, not that specific bus.

No.
--
Roland Perry

"Roland Perry" wrote in message

In message , at 20:20:28 on Mon,
19 Dec 2011, Richard J. remarked:

Er, what air conditioning?

I was sure I'd seen a reference to air conditioning in this thread,
but the only one I can find is on londonist. It's not mentioned in
the TfL press release. But the windows don't open! Are they really
intending to run a new bus in summer without air conditioning AND
with no means of opening any window? Perhaps this is another reason
for having an open rear platform, except it won't always be open.

I've seen reference to "air chillers", which is a kind of aircon-lite.

I think the driver's cab has full a/c.

On Dec 19, 5:54*pm, "Richard J." wrote:
Roland Perry wrote on 19 December 2011 17:29:16 ...

And in other news, it seems it's a perpetual motion machine in London:

* * * * *"Transport for London (TfL) said the bus recharged its battery
* * * * *using energy from its brakes, but on long journeys had to run on
* * * * *diesel."

http://www.bbc.co.uk/news/uk-england-london-16244634

But I'm glad I diagnosed the problem correctly (there's some value in an
engineering degree after all!):

* * * * *"However when the bus undertakes long, non-stopping motorway
* * * * *journeys, such as its journey to Bedfordshire this morning, it
* * * * *can lose charge and the driver is briefed to pull to the side of
* * * * *the road to allow the battery to recharge."

London to Bedfordshire is not a "long" journey. *And briefing the driver
to stop on a motorway is tantamount to inciting a criminal offence. *A
vehicle that is not able to drive from London to Luton on a motorway
should not be allowed on a motorway at all.

One wonders what the non-stop range is on a hot day with a full load and
the air conditioning at full stretch.
--
Richard J.
(to email me, swap 'uk' and 'yon' in address)

But you won't know that a vehicle is unable to drive from London to
Luton on a motorway until................................oh yes you
attempt to drive it from London to Luton on a motorway.

Let's face it vehicles break down everyday on motorways for one reason
or another, hardly a big deal is it?

In message
, at
08:52:43 on Tue, 20 Dec 2011, George
remarked:
"Transport for London (TfL) said
....
when the bus undertakes long, non-stopping motorway
* * * * *journeys, such as its journey to Bedfordshire this morning, it
* * * * *can lose charge and the driver is briefed to pull to the side of
* * * * *the road to allow the battery to recharge."

But you won't know that a vehicle is unable to drive from London to
Luton on a motorway until................................oh yes you
attempt to drive it from London to Luton on a motorway.

It sounds like TfL had an idea it would run out of battery; I wonder if
it has a "miles to empty" display [for the battery] like my ten year old
petrol car does [for the petrol]?

Let's face it vehicles break down everyday on motorways for one reason
or another, hardly a big deal is it?

Indeed, especially as this would seem to be an empty fuel tank rather
than anything more sinister.
--
Roland Perry

"Roland Perry" wrote in message

In message
,
at 08:52:43 on Tue, 20 Dec 2011, George
remarked:
"Transport for London (TfL) said
...
when the bus undertakes long, non-stopping motorway
journeys, such as its journey to Bedfordshire this morning, it
can lose charge and the driver is briefed to pull to the side of
the road to allow the battery to recharge."

But you won't know that a vehicle is unable to drive from London to
Luton on a motorway until................................oh yes you
attempt to drive it from London to Luton on a motorway.

It sounds like TfL had an idea it would run out of battery; I wonder
if it has a "miles to empty" display [for the battery] like my ten
year old petrol car does [for the petrol]?

Even if it does, I suspect it's not well callibrated on this early
build/prototype model.


Let's face it vehicles break down everyday on motorways for one
reason or another, hardly a big deal is it?

Indeed, especially as this would seem to be an empty fuel tank rather
than anything more sinister.

Which might mean that the (diesel) fuel gauge is also innacurate in this
early model.

In message , at 17:54:20 on
Tue, 20 Dec 2011, Recliner remarked:

Indeed, especially as this would seem to be an empty fuel tank rather
than anything more sinister.

Which might mean that the (diesel) fuel gauge is also innacurate in this
early model.

It could easily be broken.

--
Roland Perry

Recliner wrote:
Which might mean that the (diesel) fuel gauge is also innacurate in this
early model.


Of course, if it's like the original Routemasters, the fuel gauge is a
piece of calibrated plywood which goes through the fuel filler.

--
Tciao for Now!

John.