As the holiday season progresses, it looks like it is going to be another great year for online retailers – which means fleets of delivery trucks will be hitting the streets. U.P.S. is doing its part to make sure those delivery trucks are operating as efficiently as possible, which improves their bottom line – but more importantly, puts less CO2 into the atmosphere:

When you operate a gigantic fleet of vehicles, tiny improvements in the efficiency of each one will translate to huge savings overall — is what led U.P.S. to limit further the number of left-hand turns its drivers make.

The company employs what it calls a “package flow” software program, which among other hyperefficient practices involving the packing and sorting of its cargo, maps out routes for every one of its drivers, drastically reducing the number of left-hand turns they make (taking into consideration, of course, those instances where not to make the left-hand turn would result in a ridiculously circuitous route).

Last year, according to Heather Robinson, a U.P.S. spokeswoman, the software helped the company shave 28.5 million miles off its delivery routes, which has resulted in savings of roughly three million gallons of gas and has reduced CO2 emissions by 31,000 metric tons.