Hybrid cars

On average I drive a round 85 miles to work and back each day which is costing me abot £70 a week in fuel. I am.really think of getting a hybrid to save money but improve my carbon footprint. Looking at whats out there, I really dont know what is any good. Where I live i cant easily run a power point to car from the house, have the same issue at work. Also I have 3 grown up children so cant get someting small. Cant afford new so needs to be second hand aroung 20k market.
Help advice and suggestions please?