Saturday, September 19, 2009

The Poo-Poo Train

Funiculaire Neuveville-St.Pierre in Fribourg, Switzerland. Photo courtesy

Sometimes inspiration seems to come in the strangest of places. Since the middle of the nineteenth century, cable trains or funiculars, have probably been the most energy-efficient mode of transportation anywhere on the face of the planet.

This simple, low-tech cable train often runs on plain water and gravity. Many of them have survived and continue to be utilised (mostly in a modernized form). New systems are being developed to keep the funiculars still in operation operating smoothly. A cable train system is operated on a steep slope with a gradient of up to 55%; and, consists of two passenger cars which are connected by a steel cable. Both cars travel on the same single track which widens temporarily to two tracks (usually in the middle) so the trains can pass one another.

One famous example is the Funiculaire de Montmartre in Paris, France, which was operated by water power from 1900 to 1930 and transported one million passengers per year.

Cable trains prove extremely energy efficient because a large share of the power required to pull up the ascending car is delivered by the counterweight of the descending car. Some added water and gravity do the rest. Since the system uses only one track for the majority of the line, it saves extensively on the materials needed and there is a reduction in space required.

Diagram showing how a funicular works.

Before the train departs the station, the employee in the upper station is informed of the number of passengers that have entered the ascending car. This tells him how much water the reservoir on the descending car needs (about 80 litres per passenger) to transport the cabin from the lower platform to the upper platform.

Immediately the descending car becomes heavier than the ascending car, the brakes are loosened setting both cars in motion now using only the power of gravity to complete the trip to the opposite platform. Once the descending car arrives, its water reservoir is emptied and the process is ready to begin again and transport a new set of passengers. (I shall be the one on the platform waving everyone a safe journey!)

The employee is holding the handle which regulates the brake. This brake operates a cog wheel onto a Riggenbach cog between the rails. The only thing the employee has to do is to turn the handle during the way down depending on the speed of the cabin.

I have to admit here that while I find the entire process fascinating, my fear of heights would probably keep me from ever riding one of these. If I were in the train and I could see that view, they would probably end up having to lash me in my chair.

Photo courtesy TreeHugger.

However, no matter how simple a process is; there is always someone somewhere who can improve on it.

In Fribourg, Switzerland, they had a much better idea. The two areas of town are separated by about 375' of elevation. One area is a the bottom of the hill and one area is at the top. What to do?

Since there is always one thing that flows downhill - sewage - they decided against running in a pipe and opted instead to use the waste as the counterbalance to their funicular. It is affectionately called by some - the "poo-poo train."

Photo courtesy TreeHugger.

Below are a couple of videos showing a ride on a furnicular.

If anyone has ever ridden on these, how about leaving a comment describing your trip!

Via Low-tech Magazine, TreeHugger and Funimag.


kathi said...

We have one in Chattanooga - the Incline Railway.

Pippa said...

How exciting!! Have you ever ridden on it? What was it like?