For UK it must be turning left only,as you don't have to wait for the opposite traffic to stop.
You wouldn't think of something as benign as avoiding a left-hand turn could conserve fuel, but Atlanta-based United Parcel Service (UPS) swears by it. In fact, the parcel carrier has technology in its systems that help map this out routes that minimize the number of left turns the driver has to make. According to spokesperson Steve Holmes, avoiding left turns at intersections reduces idling which in turn lowers fuel consumption. "It seems small, but when you multiply it across 88,0000 vehicles making nearly 15 million deliveries every day during the course of a year, it adds up."
And at stop lights, making a right turn at an intersection tends to be faster than at a left turn, since you have only to wait for an opportunity to turn in one lane of traffic. You also have the option of "right on red" in most jurisdictions, unless otherwise indicated by traffic signs. "So even if you didn't save fuel, you're going to move more quickly through a route."
"Because 98% of our packages are processed electronically by shippers, we know what's entering our system each day, what's still in our system each day, when each package is going to arrive at a center, when the package is scheduled for delivery -- including time of day -- and where it will be delivered," Holmes says.
What's more, Holmes says, UPS drivers are trained to always turn off their package cars when they stop for a delivery, never idling at the curb or in a driveway. "Even if the driver is out of the truck for a few seconds, the vehicle is always turned off."
http://findarticles.com/p/articles/mi_qn4188/is_20060716/ai_n16540534
after two years.
