On 6 Jul, 09:56, Adrian wrote:
February 2006.http://www.tfl.gov.uk/corporate/medi...ntre/3680.aspx

From the article:

"The battery pack is kept at optimum power by a 1.9 litre diesel Euro
IV engine. In other words, an engine which would normally be found in
a family car keeps the battery"

1.9 sounds a bit too small. I'm sure in start and stop traffic it
might be ok but ultimately the energy all comes from that engine.
Seems to me the bus would be hopeless for any long or even middle
distance runs especially if any hills are involved, since once the
battery has been used up its relying on the engine only and a 10 ton
(probably more) bus won't be going anywhere fast with an engine that
size.

B2003

"Boltar" wrote in message
ups.com...
On 6 Jul, 09:56, Adrian wrote:
February 2006.http://www.tfl.gov.uk/corporate/medi...ntre/3680.aspx

From the article:

"The battery pack is kept at optimum power by a 1.9 litre diesel Euro
IV engine. In other words, an engine which would normally be found in
a family car keeps the battery"

1.9 sounds a bit too small. I'm sure in start and stop traffic it
might be ok but ultimately the energy all comes from that engine.
Seems to me the bus would be hopeless for any long or even middle
distance runs especially if any hills are involved, since once the
battery has been used up its relying on the engine only and a 10 ton
(probably more) bus won't be going anywhere fast with an engine that
size.


Do the buses have regenerative braking as well?

Paul

Boltar ) gurgled happily, sounding much like they
were saying :

"The battery pack is kept at optimum power by a 1.9 litre diesel Euro
IV engine. In other words, an engine which would normally be found in
a family car keeps the battery"

1.9 sounds a bit too small. I'm sure in start and stop traffic it
might be ok but ultimately the energy all comes from that engine.
Seems to me the bus would be hopeless for any long or even middle
distance runs especially if any hills are involved, since once the
battery has been used up its relying on the engine only and a 10 ton
(probably more) bus won't be going anywhere fast with an engine that
size.

Don't forget that the engine is basically just being used as a generator,
therefore can run at optimum revs for the specific output - there's no
requirement for any kind of useful rev range or torque curve.

On 6 Jul, 11:05, Adrian wrote:
Don't forget that the engine is basically just being used as a generator,
therefore can run at optimum revs for the specific output - there's no
requirement for any kind of useful rev range or torque curve.

True , and I suppose that will mitigate it somewhat. However
ultimately that engine will produce less power than a normal bus
engine so when relying on the engine alone its going to be slower
compared to the normal engine running at optimum gearing.

B2003

Boltar ) gurgled happily, sounding much like they
were saying :

Don't forget that the engine is basically just being used as a
generator, therefore can run at optimum revs for the specific output
- there's no requirement for any kind of useful rev range or torque
curve.

True , and I suppose that will mitigate it somewhat. However
ultimately that engine will produce less power than a normal bus
engine so when relying on the engine alone its going to be slower
compared to the normal engine running at optimum gearing.

shrug
How often do bus engines require full power? Not very.

Don't forget that one thing electric motors are very good at is producing
large amounts of torque from rest.

On 6 Jul, 11:16, Adrian wrote:
shrug
How often do bus engines require full power? Not very.

Agreed but when they do need it they really need it. The steep hills
around mill hill, highgate , hampstead and southgate spring to mind. A
hybrid bus with an exhausted battery going up one of those hills won't
be very popular with other motorists.

B2003

Boltar ) gurgled happily, sounding much like they
were saying :

shrug
How often do bus engines require full power? Not very.

Agreed but when they do need it they really need it. The steep hills
around mill hill, highgate , hampstead and southgate spring to mind. A
hybrid bus with an exhausted battery going up one of those hills won't
be very popular with other motorists.

Nor would a diesel bus with an empty fuel tank...

I really don't think it's going to be an issue.

On 6 Jul, 11:35, Adrian wrote:
Boltar ) gurgled happily, sounding much like they
were saying :

shrug
How often do bus engines require full power? Not very.
Agreed but when they do need it they really need it. The steep hills
around mill hill, highgate , hampstead and southgate spring to mind. A
hybrid bus with an exhausted battery going up one of those hills won't
be very popular with other motorists.

Nor would a diesel bus with an empty fuel tank...

I really don't think it's going to be an issue.

A buses diesel fuel probably lasts all day. If these hybrid buses are
anything like hybrid cars then the battery would run down after only a
few miles without topping up which means its quite possible the bus
could be relying on engine power alone on difficult routes such as I
mentioned if the engine doesn't have the surplus to charge the battery
as well as supplying the motors.

B2003

Boltar wrote:
On 6 Jul, 11:16, Adrian wrote:
shrug
How often do bus engines require full power? Not very.

Agreed but when they do need it they really need it. The steep hills
around mill hill, highgate , hampstead and southgate spring to mind.

Even if the buses were unsuitable for those areas, that's only about a dozen
routes. You wouldn't say that double deckers will never work in London
because of the Rotherhithe Tunnel.

On Fri, 6 Jul 2007 12:26:49 +0100, "John Rowland"
wrote:

Boltar wrote:
On 6 Jul, 11:16, Adrian wrote:
shrug
How often do bus engines require full power? Not very.

Agreed but when they do need it they really need it. The steep hills
around mill hill, highgate , hampstead and southgate spring to mind.

Even if the buses were unsuitable for those areas, that's only about a dozen
routes. You wouldn't say that double deckers will never work in London
because of the Rotherhithe Tunnel.


True, as double deckers have been used in it, haven't they?