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Badjelly
30th September 2009, 15:01
This has been discussed on the Wellington Parking (http://www.kiwibiker.co.nz/forums/showthread.php?t=106738) thread, but it's a bit off-topic there and I think it deserves its own thread. There's a general vibe about the place that public transport is fuel efficient because you've got lots of people on the one vehicle. However this ignores the fact that most public transport systems achieve low average occupancy rates, because at peak times the buses and trains are full only in one direction and during the rest of the day they aren't full at all. I saw a really good discussion of this on a blog once, but I can't recall where. I'll keep looking.

A quick Google search came up with this

http://www.publicpurpose.com/ut-en2002.htm

As the title says, automobile and public transport fuel efficiency (per passenger kilometre) are pretty similar.

I don't particularly trust the site this appears on (they seem to be libertarians--who are well known to be a little careless about facts--and they think BTU/kilometre is a metric measure) but I think the USDOE report they base it on is pretty solid.

Does anyone have any idea how the numbers stack up for public transport systems in NZ?

Perhaps what we need to be encouraging is low impact personal transport.

Badjelly
30th September 2009, 15:15
I saw a really good discussion of this on a blog once, but I can't recall where. I'll keep looking.

Here it is

http://www.templetons.com/brad/transit-myth.html

See also

http://www.templetons.com/brad/robocars/transit-ends.html

But before you get too enthusiastic about the end of public transport, have a look at what this bloke thinks should replace it: robot cars!

http://www.templetons.com/brad/robocars/robot-cars.html

The Stranger
30th September 2009, 15:20
I did see a study done on it once and their conclusion was that essentially it fell along the lines of weight per passenger. The higher the weight per passenger the worse the impact on fuel usage and emissions.

From worst to best.
Trains
Busses
Cars
Motorcycles

That said, public transport would probably save over all in reducing the costs and impact of additional roading.

slofox
30th September 2009, 16:05
The benefit of public transport, I think, is that fact that less vehicles are on the road at once. The fuel consumption aspect is not a compelling argument in my book.

BUT. It could be a compelling argument if different vehicles were used for public transport. Why not use more, smaller vehicles rather than fewer huge great diesel belching omnibuses. In a place like the Tron, the buses run mostly empty for most of the day. A vehicle of half the size of the buses, or even less, would work as well and be more fuel efficient. During peak hour, just put more of the smaller vehicles on. Have 'em run more often when busy, less often when not...

Or is that too easy..?

Badjelly
1st October 2009, 08:24
The benefit of public transport, I think, is that fact that less vehicles are on the road at once. The fuel consumption aspect is not a compelling argument in my book.

Nor mine, obviously, but I think a lot of people think it is.


BUT. It could be a compelling argument if different vehicles were used for public transport. Why not use more, smaller vehicles rather than fewer huge great diesel belching omnibuses. In a place like the Tron, the buses run mostly empty for most of the day. A vehicle of half the size of the buses, or even less, would work as well and be more fuel efficient. During peak hour, just put more of the smaller vehicles on. Have 'em run more often when busy, less often when not...

Or is that too easy..?

First, I think the larger bus will use less fuel per passenger when both the large and small bus are full. But when each of them is taking, say, 10 passengers the smaller one will win. So smaller buses might well win overall.

However I think the big issue is more, smaller buses = more drivers. Labour must make a big part of the costs of public transport.

Swoop
1st October 2009, 08:40
The most impressive form of public transport that I have personally encountered, was in a small area of England.
During the day, after peak commuting time, the larger busses were removed from the roads and replaced with much smaller mini-busses or even mini-vans. These smaller vehicles were normally 3/4 full and they served quite a few backroads on their way in to the local township.
I laugh when there is a scania or mercedes bus winding around the suburbs of d'Auckland with possibly one passenger on it. Efficient form of ecologically friendly, public transport?:crazy:

Even Vanuatu has a better system. A hiace van with a registration plate beginning with a letter "B" means it is a bus. Always busy with people!