For whatever reason the issue of air-conditioned gondolas seems to be a touchy subject around here at The Gondola Project. Everyone has a different opinion and no one seems to think it can happen.
So . . .
For everyone whose been asking (and there’s been a few), I’ve dug up the identity of the only known gondola system to be air-conditioned: It’s the Muttersbergbahn near Bludenz, Austria.
Details are still scant. I’m not sure if the system is still in operation or was a demonstration piece. Is each cabin air-conditioned or (like the Rheinseilbahn’s Urban Concept vehicles) were just a few selected to show the potential?
So while we don’t have all the information yet, we can say this: Battery-based gondola AC systems have been designed, tested and installed.
I’m sure that until someone sees it with their own two eyes, this will still be a matter of controversy and contention. But until then (hopefully), this should ease people’s worries.
As always, any German-speaking readers with more details are encouraged to post their findings in the comments. And – of course – I’ll endeavor to visit the system whenever time, schedule and budget permits.
8 Comments
Im interested to find out more.
There is no sign of an AC unit mounted in the ceiling from photos I’ve seen.
It does have an some kind cable above the cabin though which is promising.
http://www.flickr.com/photos/fallinhigh/3162882917/#/photos/fallinhigh/3162882917/lightbox/
Theirs a better photo on wiki commons
http://upload.wikimedia.org/wikipedia/commons/e/ed/MuttersbergBahn.JPG
Im still not sure what the cable is for, but i don’t think cabin pictured is air-conditioned. We would see the unit or batteries (i would have put them under the seats.
You know I was hopeing you’d come back to this. The way I see it, urban gondola’s will need a better electrical system then they have now to be accepted as public transit. The manufacturers need to make this a high priority and I believe it is completely doable.
If you’ll forgive me, this is rather long.
To start with A/C is a luxury; a luxury everyone expects on a transit vehicle and one that’s very important in countries like Canada where public transit has a lot of competition, but a luxury none the less. Heating isn’t. At least not in a place like Toronto. There are other power draws to: panic buttons, emergency phones, probably cameras, announcement systems, displays, ventilation, lights (real transit runs at night), communication and telemetry to support all that. All communication will have to be wireless and that entails extra power. The trend these days is for more and more information technology in public transit, and that means more power usage. A highly robust electrical system is a must.
The present system is batteries, assisted by solar panels and top ups in the stations. I say assisted because the batteries bear the brunt of the load. Solar panels small enough for a gondola provide little power and batteries charge too slowly to be fully topped up in the stations. That means most of the power for a service period has to be stored in the batteries. That means big batteries. It gets more problematic if you run your gondola system for most of the day. Each cabin will need at least several hours a day out of service for charging, and if the system can’t be shut down long enough at night, you’ll have to take some cabins out of service in shifts. That means running at partial capacity at least part of the time and complicates operations. The more electrical systems you add to the cabins the worse it gets.
This system could be substantially improved by replacing the batteries with supercapacitors. These are new, but proven technology and while they have only a fraction the energy density of modern batteries, they charge (and discharge) much faster. A supercapacitor can be fully charged in seconds if you have enough current available. That makes full charging in stations practicable. They could even be topped up a little at each tower. Since the capacitors would only need enough charge to run for a few minutes between stations (plus a suitable reserve to run essential systems in an emergency) they might actually be lighter then the batteries they replace. They also last for millions, rather then thousand of charging cycles so they might well last for the life of the cabins.
BDG and 3S systems offer a very simple and elegant solution. Simply drive a generator from one of the pulleys riding on the stationary support cable. As long as the cabin is in motion, power is available. Conductive rails would provide power when the cabin slows down in stations. The simplicity and low cost of the system would more then make up for the small inefficiency of electrical to mechanical to electrical conversion.
I also believe it is perfectly feasible to power cabins via ‘overhead wire’. I was able to design such a system in my head in only a few hours using a wire hanging below the cabins.
A better electrical system is essential for urban gondolas, and if I can think of three in a few hours, Doppelmayr should be able to come up with something.
Erik,
Don’t worry about long posts. As I understand it, supercapacitors are actually what are used in the Muttersbergbahn. They’re used for exactly the same reason you’ve outlined, so good spot!
As for your other idea, it’s basically a “third rail” concept. While the industry’s bottom-supported systems have third rails providing electricity, the same concept has never been adapted to an aerial gondola system – at least to my knowledge.
Would certainly be something to think about.
What happened? All the recent comments are gone.
I like the idea of driving a generator off one of the support sheaves, though I don’t know if it would have enough traction on the track rope to generate power for an A/C unit.
For a 3S, it might be possible to simply run power through the track ropes. The system would have to be carefully designed so that the ropes were electrically isolated from each other, of course (though all the bullwheels and sheaves have rubber liners anyway, so that might not be a big issue).
Remember these sheaves support the whole weight of the cabin. Traction isn’t a problem.
why no just roll down the windows?