I currently work as a lab microbiologist. One place where potential energy is added to the system to keep things in motion is the spring in a manual pipette. Pressing the plunger compresses the spring which stores energy which then draws liquid into the tip when released. Lifting the filled tip adds a small amount of gravitational potential energy. Another place where potential energy is added to the system is the spring in the door of the autoclave. When the door is closed, the springs store energy to keep a tight seal. I would estimate some of the autoclaves I work with have doors that are 30kg each. The gravitational potential energy of a 30kg door lifted 1m would have 294J of gravitational potential energy