The Green Dragon
, a roller coaster at Greenwood Forest Park, a family 'attraction' in Wales, generates more power than it uses. How is this possible? It's all those stairs ...
There are three 'components' to the system
: the coaster train itself, a tram car, and a piece of 'carrier track' used for raising the coaster train back to the top of the run.
Sequence of operation seems to be something like this:
1) Previous ride is done, the coaster train is at the bottom of the run, as is the tram car. The 'carrier track' is up at the top. The carrier track is linked to the tram around a pulley system, and as it is heavier than the empty tram, it now drops to the bottom, pulling the tram car to the top.
2) While that is going on, the next group of riders is climbing the stairs to the top level of the system.
3) Once the carrier track is at the bottom, the empty coaster train is rolled onto it. The group of riders board the tram at the top, and as this is now heavier than the carrier track, it drops to the bottom, pulling the track and train to the top.
4) Riders get out of the tram car at the bottom, and again walk back up to the top, where the coaster train is now waiting for them. They get in, and enjoy their ride ...
5) Repeat ...
Sample rider report: "I really like this coaster. It gets quite fast when you get into the helix. It's also good for the environment, and good for you with all the walking."
Here is a short YouTube video
of the components of the system.