It's called a GOLF cart for a reason.
Get a hybrid or electric car.
These vehicles have evolve beyond the golf course. Folks use them as grocery getters more than golf carts these days. There is a whole class of these (LSVs vs golf carts) designed for short distance travel.
http://en.wikipedia.org/wiki/Low-speed_vehicle
IMHO, forcing people to purchase a fourty thousand dollar car if they want to be green is not the right answer.