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You just went shopping without taking a single step – let alone leaving any carbon footprints. And increasingly green shipping practices mean fewer tons of carbon dioxide emissions are being delivered along with the books and clothes and gadgets and personalized gizmos ordered by online shoppers.

Driven by corporate responsibility – and higher fuel costs – shipping companies such as FedEx and UPS are looking to get the most out of a gallon of fuel – in the air and on the ground.

FedEx, for example, is updating its fleet of aircraft to save fuel and cut costs. The Memphis-based company is replacing Boeing 727 jets with Boeing 757s, which will cut reduce fuel consumption by 47 percent. Changes in ground operations have also resulted in fuel savings. The reduction of aircraft auxiliary power unit usage while at the gate is saving one million gallons of jet fuel per month.

Shipping companies are also making changes in their fleets of vans and trucks that criss-cross cities and towns across the globe.

The UPS green fleet – comprised of more than 2,500 alternative fuel vehicles – has traveled more than 200 million miles since 2000. The fleet goes beyond hybrid-electric vehicles and all-electric vehicles. The Atlanta-based company has more than 1,000 package delivery vehicles in the United States, Germany, France, Chile and Brazil burning compressed natural gas (CNG). A CNG vehicle emits 95 percent fewer particulates than a diesel counterpart. Carbon monoxide emissions are 75 percent lower and nitrogen oxide emissions are 49 percent lower.

DHL Express operates 30 battery-powered electric vans and 50 hybrid trucks in Manhattan that reduces CO2 emissions by more than 50 percent compared to conventional vehicles.

The green vehicles used in New York City by DHL Express are built in the United States by Azure Dynamics, a world leader in the development and production of hybrid electric and electric commercial vehicles. Ford Motor Co. has produced the chassis for these vehicles. The Balance Hybrid Electric vehicle components combine Azure’s hybrid powertrain with a Ford E450 chassis. Converting DHL’s existing Ford E450s into hybrids improves fuel economy by up to 40 percent and lowers emissions by about 30 percent. Azure puts its Force Drive electric powertrain into new Ford Transit Connect vans. The lithium-ion battery power vans have a range of up to 80 miles and can be recharged overnight.

Even the financially troubled United States Postal Service has increased the use of alternative fuels by 133 percent since 2005. About 35 delivery vehicles in Key West, Florida have been converted to run on propane and mail is being delivered by three-wheel electric vehicles in Florida, California and Arizona. The vehicles have a range of 40 miles and cost 2 cents a mile to operate.

The USPS also notes that many mail carriers still deliver via the most fuel-efficient way possible – on foot. The USPS “fleet of feet” delivers mail door-to-door by walking nearly 9,000 mail delivery routes every day.

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