On Mon, 19 Feb 2007 sweek wrote:

How are they more attractive? Definitely not more attractive-looking,
and a tram has a higher capacity, unless they come up with a way of
letting double deckers under them.

The only trolleybuses I have ever been on were double-deckers.
--
Thoss

On Mon, 19 Feb 2007 10:40:34 +0000, Ken wrote:

On Sun, 18 Feb 2007 20:06:31 +0000, Marc Brett
wrote:

On Sun, 18 Feb 2007 19:41:22 +0000, stevo wrote:

London would be foolish to go for trolley busses as hydrogen power will
be round soon(ish)

Hydrogen "power" is a fraud, the sooner abandoned the better.

http://www.thenewatlantis.com/archive/15/zubrin.htm

Much of this confirms what I'd suspected. But what about the points
made about fuel cells? Surely the current trials in London and
elsewhere of buses using this technology have been less expensive and
more reliable that this author would have you believe is possible?

http://www.tfl.gov.uk/tfl/press-cent...nt.asp?prID=73

"The high cost of the vehicles is the major barrier at the moment but providing
the Government continues to provide support for this promising technology, it
could be a viable option for the future."

Translation -- not economical today, and no timetable for economical operation,
ever.

"The buses have excelled in reliability and have been very popular with
passengers who have appreciated the amazing environmental benefits of fuel cell
technology and the quiet, smooth ride the buses offer."

How the average passenger appreciates the "amazing" environmental benefits when
there are none is a mystery to me. The "quiet, smooth ride" equally can be
obtained with trolley buses at far less cost, I suspect.

On Sun, 18 Feb 2007, Marc Brett wrote:

On Sun, 18 Feb 2007 19:41:22 +0000, stevo wrote:

London would be foolish to go for trolley busses as hydrogen power will
be round soon(ish)

Hydrogen "power" is a fraud, the sooner abandoned the better.

http://www.thenewatlantis.com/archive/15/zubrin.htm

A good article, although i think it's a bit over the top; whilst there are
several very good reasons why the hydrogen economy is bunk, he generates
more by fallacying his way from "we can't do it" to "it can't be done",
which weakens his credibility. His obsession with terr doesn't help
either, but then is is a yank. And given that this is Robert Zubrin we're
talking about, it's actually quite a restrained article!

tom

--
Don't anthropomorphize computers: they don't like that.

On Feb 19, 9:46 am, "sweek" wrote:
How are they more attractive? Definitely not more attractive-looking,
and a tram has a higher capacity, unless they come up with a way of
letting double deckers under them. Trams also simply attract more
people since buses have a more negative and slower image.

If theres definately no option of a tram system being put in because
of cost then trolleybuses would have their place. Even if they don't
attract more passengers they wouldn't belch out any fumes into the
street which is always a good thing (even if the power station does -
but at least thats miles away).

B2003

On 19 Feb, 12:45, "Boltar" wrote:
On Feb 19, 9:46 am, "sweek" wrote:

How are they more attractive? Definitely not more attractive-looking,
and a tram has a higher capacity, unless they come up with a way of
letting double deckers under them. Trams also simply attract more
people since buses have a more negative and slower image.

If theres definately no option of a tram system being put in because
of cost then trolleybuses would have their place. Even if they don't
attract more passengers they wouldn't belch out any fumes into the
street which is always a good thing (even if the power station does -
but at least thats miles away).

B2003

In terms of pollution, the figures quoted on the website link are as
follows: -

CO2 Emissions Range (NYC Duty Cycle)
"Clean Diesel" 4,469 - 4,563 g/km
Hybrid Diesel-Elec 2,500 - 3,438
Trolley (UK grid) 1,744 - 2,189
Trolley(renewables) 0

So even with conventional electric power, trolleybuses emit less than
half the CO2 of conventional diesel buses and no particularates ( a
known cause of asthma)
Assuming the electricity was generated using renewables like Wind the
pollution levels approach 0.

The big advantage of the newer syle trolley bus over trams is their
ability to move round obstructions and the fact that they can be
independent of wires for several miles.
In Rome and Shanghai for example, they consciously chose this form of
operation in areas where overhead wires were excluded for
environmental/ conservation reasons.

While this requires a weight overhead in battery power, it makes them
flexible enough to compete with conventional diesel buses on certain
routes.

I am glad to hear the hybrid test is going well too.

Probably what will be needed will be a variety of systems such as
Tram, Trolley and Hybrid - aimed at reducing CO2 emissions.

P.S. The issue of hydrogen doesn't really belong in this thread, but
is debatable

On 20 Feb, 08:36, wrote:

I am glad to hear the hybrid test is going well too.

Probably what will be needed will be a variety of systems such as
Tram, Trolley and Hybrid - aimed at reducing CO2 emissions.

I should have said "Fuel Cell" not "Hybrid" in the above section.

to repeat the link showing a trolleybus with battery power: -
http://www.youtube.com/watch?v=kSxTniqh_EQ

There seems to be some interest as the number of hits has been over
100 in the past week!

On Feb 20, 8:36 am, wrote:

Assuming the electricity was generated using renewables like Wind the
pollution levels approach 0.


Nothing is zero emmisions, it still has to be manufactured, scrapped
at the end of its life, the power has to be distributed and
maintained.

Kevin

On Feb 20, 8:36 am, wrote:
While this requires a weight overhead in battery power, it makes them
flexible enough to compete with conventional diesel buses on certain
routes.

I can't see battery power being useful for more than a mile or so and
in hilly areas I suspect its a non starter - literally. The other
problem is that if an operater buys a trolleybus with a diesel
engine , you can guarantee that at some point the bean counters will
say "well hang on , this bus has an engine anyway , why are we paying
to maintain overhead wires when the bus doesn't actually need them?".

B2003

On 20 Feb, 09:39, "Kev" wrote:
On Feb 20, 8:36 am, wrote:

Assuming the electricity was generated using renewables like Wind the
pollution levels approach 0.

Nothing is zero emmisions, it still has to be manufactured, scrapped
at the end of its life, the power has to be distributed and
maintained.

Kevin

This depends on how power is produced.
It's an issue beyond the scope of this newsgroup, but as a matter of
scientific principle, all of the things you mention can be done
without producing any CO2 whatsoever.

On 20 Feb, 10:17, "Boltar" wrote:
On Feb 20, 8:36 am, wrote:

While this requires a weight overhead in battery power, it makes them
flexible enough to compete with conventional diesel buses on certain
routes.

I can't see battery power being useful for more than a mile or so and
in hilly areas I suspect its a non starter - literally. The other
problem is that if an operater buys a trolleybus with a diesel
engine , you can guarantee that at some point the bean counters will
say "well hang on , this bus has an engine anyway , why are we paying
to maintain overhead wires when the bus doesn't actually need them?".

B2003

The figures quoted for the Rome trolleybuse are I think, 7-10 km.
The battery starts recharging as soon as it goes back on the wire.
It also uses re-generative braking and does some charging during
turnaround at the depot.

As for the gradient issue: actually electric trolleybuses have better
hill-climbing abilitities than diesels.
Electric power provides better torque than any internal combustion
engine.
San Francisco has operated a large fleet for 25 years or so, so I
don't see that being a problem in London.

The initial investment in wiring is recouped by long term operational
advantages.
Installing diesel engines obviously makes no sense.

Diesels in cities are a lousy idea and should be phased out of London.