It goes without saying that delivery companies give serious thought to the routes they use. Anyone starting out on the problem of vehicle routing would naturally look for the shortest distances and the fastest roads in order to complete deliveries efficiently.
UPS, however, breaks from common sense with its no-right-turnpolicy (in the UK, that is). Literally, by routing its trucks to take predominantly left-hand turns at junctions, the company is achieving massive efficiencies and savings.
The idea is this: turning right at junctions requires cutting across a lane of on-coming traffic, which subsequently requires longer wait times (thus fuel) and a higher risk of accidents than simply turning left on to the closer lane. Since adopting the policy, around only 10% of UPS truck turnsare to the right.
Despite this approach often resulting in longer distance journeys, the time saving has allowed the company to cut the number of trucks it uses by 1,100, thereby reducing total distance travelled by 28.5m miles. Consequently, this saves 10 million gallons of fuel, emitting 20,000 tonnes less CO2, while delivering 350,000 more packages every year.
This impressive and unconventional strategy comes out of the field of ‘vehicle routing problem’ (VRP) - which since its inception by George Dantzig in 1959 remains an active area of management science. VRP uses mathematical formulas to calculate the best route between a set of points, and has been applied in diverse settings; from delivery and taxi fleets to catching chickens on a farm.
The results of UPS’s no-right-turn policy raise the question; why don’t all road users apply the rule? The answer is a matter of collective effect versus the results seen by individuals. That is to say, although traffic in total will be more efficient not all routes will be faster, and people are unlikely to comply unless it benefits them directly.
Like with many environmental policies, it only takes a few people opting out to make the whole thing fall apart. As commented in an article by The Conversation, ‘[this] is a good example of the prisoner’s dilemma, the famous game theory problem’ in which individuals break the rules to take advantage of group compliance.
A no-right-turn policy may then have to be enforced by government rather than rely on public volunteerism. This behavioural change would no doubt be unpopular at the outset, but if UPS can save 10 million gallons of fuel in a year and countless hours stuck in traffic, just think what an entire city could save.
This is a summary of an article in The Conversation, January 2017.
This post was compiled on behalf of Weald Technology by Hugh Reed, April 2017.
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