Giving a car away

Hi, tomorrow (Friday) I will give my car to a man who runs a car repair business. It is not cost effective for me to repair it. I don't want any money for it because it is saving me a lot of inconvenience. But legally is there a requirement for some money to change hands ? I ask this because I seem to remember that when I took my Vectra to an Opel garage and asked them to scrap it there was a token payment. I cannot remember in which direction.