The idea of using a stationary bike to generate energy is being done here in the Philippines. In a City Jail to be exact. The inmates are required to use the stationary bikes to charge a battery that powers their lights at night. They do take turns and are required to do this. The article can be seen here
Jail guard’s invention saves on power - INQUIRER.net, Philippine News for Filipinos with the photos and all.
Just an idea I wanted to share, since they are using an ordinary outdoor bike I believe it won't last in the long run. Wouldn't it be a great idea if they purchased used stationary bikes (buying a new one costs $$$) and use the recumbent stationary bike instead of the upright stationary bike (for those who doesn't know the difference check this site
used stationary bikes it has photos of different kinds of stationary bikes) to maximize the usage of the bike since it is more relaxed. What do you guys think?