I'm working on a protoype that uses energy from the sun (PV cells) to convert potential energy into electrical energy . This is the basic structure. A weight is initially attached to the chain. (The chain can only hold 12 pounds) The motor(s) drive the weight up during the day and then after being sensed at the highest position by sensors, the weight falls down driving a motor an thus producing electricity. I rather seem to have a few problems increasing or maximizing the system's efficiency. Can anyone shed any light towards that direction because I really need to have this project finished before tomorrow.