The prison called Santa Rita do Sapucaí in Brazil had found new source of regenerative energy that can even motivate prisoners to get in good shape. The idea came from the judge José Henrique Mallmann, he has seen in other prisons that were giving incentives for riding bikes. So, he considered updating this idea to new charging bikes that can provides enough power to a battery that gives light to a street-light. The idea is that for every 16 hours spend riding (charging) the stationed bike, each prisoners will have a day off of their sentences. The voluntary program seems to be well integrated and many of them think it’s a very good idea and even says it keep them in good shape while making them feel good to do something that can help the society.