Excavation Vacuum

[Huge]

Not a bad attitude, given how late and over budget it was.

[SteveW]

I have been thinking that since Manchester started putting trams back in a couple of decades ago. Unlike the trams it'd have caused minimum disruption during installation and with relatively small battery or a diesel engine, they could deviate from the power lines for short diatances to get around temporary obstructions, faulty power lines, etc.

The trams do have the advantage on some routes that ex-railway lines provide much of the route ready built.

SteveW

[SteveW]

Coal fired power station 38% efficiency; distribution network 8% losses. Leaving 35% efficiency. Minus a bit for controller and motor electrical losses.

Common rail, variable turbocharger diesel engine anything between 40% to

50% efficiency. Minus mechanical transmission losses and fuel use when idling.

Hybrid diesel electric buses would likely be more efficient than electric trams and a whole lot less disruptive.

SteveW

[DerbyBorn]

I agree that the steel wheel on rails gives the lowest rolling resistance - but the trams are really heavy - therefore they consume more materials in their construction. The preparation for laying track is enormous - drains, sewers and other sevices have to be moved from under the route to avoid future disruption. The track has to be isolated to prevent vibrations from damaging buildings. There is also a overhead installation (ok - only one wire). To compare - a trolley bus can operate on a normal road, probably weighs less than a diesel bus and can be re-routed at much less cost than a tram.

I still feel that trams are viewed by councils as a sign of prosperity and hope for the future. I don't believe they properly justify not having trolley buses.

However, where significant useable railway track exists then I concede there is a case to be made for a tram - or light railway.

[dennis]

They suffer the same big problem as buses and trains.. you only need them for an hour in the morning and an hour at night. The rest of the time they are running near empty and wasting all the energy they have supposedly saved. The more routes you add to make them convenient the more they waste. The more frequent you run them the more they waste.

Buses need to be replaced with small electric cars that you just use for the journey and then leave them for someone else. They only need to do about 20 mph as a bus isn't going to average more than that if its stopping at stops. You can always chain them together for rush hour as little trains and leave them as individuals outside rush hour.

Of course the general public will wreck them and then complain there is no transport.

[MattyF]

I think they used a lot of trailers for special outings. You can see overhead wires for electric trams. The horse trams were long gone. That was the one Baldwin steam tram that they had in Christchurch NZ, where there are no hills. The Baldwin has vacuum brakes generated by steam, and a hose is connected to all the trailers to operate their brakes. I doubt that those trailers would be suitable behind electric trams which had electric brakes.

[Gazz]

i wonder who is going to be the first to post a utube video of themselves using the vacuum truck for a BJ

[manatbandq]

Which will only be needed for an hour in the morning and an hour at night...

[whisky-dave]

São Paulo is a monster. Enormous, intimidating and, at first glance at le ast, no great beauty. It's a difficult city for the traveler to master and one that may not seem worth the sweat. Even the most partisan paulistano - resident of São Paulo city - will rail about the smog, the traffic, the c rumbling sidewalks and the gaping divide between poor and rich.

[dennis]

Yes, but they won't be running around empty just in case there is a passenger.

We need robot drivers first.

[Nightjar]

It must have been quite a sight, seeing that come down the street.

Colin Bignell

[Sam Plusnet]

Na!

Jetpacks.

[meow2222]

... in the best of circumstances. IRL the ever changing speed of vehicle engines keeps them far from their most efficient.

NT