Whether it's a pair of jeans, a bottle of soda, or a new computer, everything we buy comes from somewhere, and usually that somewhere isn't particularly close. Our purchases have to travel from the factory to a warehouse to a store, or directly to your house—travel that produces a lot of emissions. All told, the U.S. freight system accounts for about 500 million metric tons of carbon dioxide per year—more than is used to light, cool, heat, and ventilate the country's commercial office space and power all the equipment in it. While emissions from moving people around are declining, those from moving stuff around are rising steadily. By 2040, freight emissions are projected to grow by 40 percent.

Freight presents a "low-hanging fruit" opportunity to reduce oil consumption and carbon emissions quickly and relatively inexpensively. A study by the Carbon War Room, a Washington, D.C., nonprofit, found that if the heaviest trucks in the U.S. commercial fleet adopted seven currently available fuel-efficiency strategies, like predictive cruise control and anti-idle devices, they would emit 624 million fewer metric tons of carbon dioxide over 10 years and save an average of $26,400 in fuel costs per truck. If nothing is done, emissions from heavy trucks will grow by 29 percent over the same period, releasing close to 4 billion tons of carbon into the atmosphere.

"Companies have tens of thousands of vehicles, and they have to fuel those vehicles," explains Aaron Sanger, until recently the director of U.S. campaigns for ForestEthics, which, along with the Sierra Club, is trying to convince companies to slash oil consumption and reduce or eliminate oil derived from Canadian tar sands, the dirtiest oil on earth. (See "Tar Sands and Soda," below.) "Those are the companies that have to shoulder the responsibility to be part of the solution."

Environmentalists aren't the only ones interested in addressing fuel efficiency. Forward-thinking companies are working to improve the efficiency of their fleets, enticed by savings on fuel costs and by programs like the U.S. Department of Energy's National Clean Fleets Partnership and the EPA's SmartWay partnership, which offer companies incentives to increase fleet efficiency and reduce emissions. Plus, carbon reductions give companies something to brag about in their annual sustainability reports.

"Companies are learning that, 'Hey, we're getting these sustainability wins, and we're getting cost savings.' So there's a certain momentum behind it," says Jason Mathers, senior manager for supply chain logistics at the Environmental Defense Fund.

Here we spotlight four companies, each of which has taken a different approach to transportation efficiency. None is perfect, but they set the stage for other companies to come along and be even greener. "You make a little change here and a little change there, and then you've made a difference," explains Mike Payette, director of fleet equipment for Staples' North American commercial division. "There's not one single answer. There's just a lot of little things that anybody could do."

Ocean Spray's Cranberry Express

In 2008, when juice company Ocean Spray took stock of its carbon footprint, it discovered that transportation was the single greatest source of emissions, accounting for more than 17 percent. The agricultural cooperative of more than 600 cranberry and grapefruit growers had committed to reducing greenhouse gas emissions by 25 percent between 2008 and 2015, and like any business, it also wanted to save money. Redesigning its transportation network offered an opportunity to do both.

One change Ocean Spray made was siting a new manufacturing and distribution center in Lakeland, Florida, near its growing southeast customer base, in 2011. This resulted in the elimination of 4.5 million truck miles each year, cutting costs by 10 percent and carbon emissions by 17 percent.

Tar Sands and Soda

In May, the Sierra Club joined with environmental group ForestEthics to launch Future Fleet, a campaign to slash oil use and reduce tar sands fuel use by America's corporate vehicle fleets. Among its first efforts: convincing soda giants Coca-Cola, PepsiCo, and Dr. Pepper-Snapple—which together own more than 100,000 vehicles—to improve their fleets' fuel efficiency by 25 percent and to buy fuels that come from tar sands-free refineries.

Soon after opening the new center, Ocean Spray found another way to eliminate truck miles: It switched to trains. It turned out that rival company Tropicana was shipping fruit from a rail terminal near the Lakeland distribution center to a terminal near Ocean Spray's distribution center in New Jersey. Then Tropicana was paying to send roughly 175 empty boxcars back to Florida to be refilled. Those empty cars could easily be filled with Ocean Spray beverages, which were currently traveling the same corridor by truck.

The benefits of the rail arrangement were obvious, but the details were still daunting. The two companies were competitors, after all. It was fine to share the use of the boxcars, but they didn't want to share details about their shipments. The solution was to have a logistics company called Wheels Clipper act as a firewall between the two shippers so that no sensitive information could leak out. Today, Ocean Spray has shifted 80 percent of its freight traffic from New Jersey to Florida from truck to rail, reducing transportation costs by 40 percent and carbon emissions by 68 percent, equivalent to more than 1,300 metric tons of carbon dioxide.

To Ocean Spray sustainability officer Kristine Young, the lesson is clear: When you're leaking carbon, you're probably also leaking money. "I'll say quite honestly that we looked at these logistics changes for business reasons and therefore for cost savings," she explains in an MIT Center for Transportation webinar on the topic. "But we have really been able to see how tracking carbon will lead us to more cost savings."

Staples Rocks Down Electric Avenue

Staples is taking its environmental responsibilities seriously. The office supply retailer stocks earth-friendly products, minimizes waste and packaging, accepts electronics back at the end of their life span for recycling, and relies on renewable power for all of its U.S. electricity use—actions that explain why it consistently ranks high on lists of the nation's greenest companies. But when Staples began upgrading the fleet of trucks that deliver goods to customers in 44 U.S. states and Canada, it could have been motivated by pure pragmatism. A variety of regulations designed to cut back on diesel pollution have made both diesel fuel and diesel engines much more expensive.

"As long as I have to pay more money to run my truck down the road, why not pay more money to run it in an environmentally sustainable manner?" asks fleet equipment director Mike Payette.

Payette admits to having a passion for the arcana of sustainable fleet management. Each change to the fleet is carefully tested and measured, and those that don't deliver fuel savings are abandoned. Some jettisoned changes include using trucks with hybrid engines, fueling with biodiesel, maintaining tire pressure with the use of inert gases, and banning left turns. While these may work for other companies, he says, they were a bad fit for Staples delivery trucks, because either the savings didn't materialize, the technology wasn't dependable, or the change slowed down deliveries.

"It's matching the right type of technology for your fleet," Payette explains. "Just because it worked for you doesn't mean it's going to work for us. Just because it didn't work for us, I wouldn't discourage anybody else from trying it."

So what has worked? Several small changes and one big one. Packing more freight onto larger trucks has reduced the overall number of trucks being fueled. Using technology to decrease truck speeds and keep drivers from idling has improved fuel efficiency. Together, these measures have reduced fuel use by more than 20 percent since 2007. "Any time you use technology to take the driver's decision making out of the picture, you get either good results or poor results, but you get results that can be monitored and are the same day in and day out," Payette notes.

Flashier than these efficiency improvements are Staples' 53 all-electric delivery trucks. An electric truck costs about three times more to purchase than a conventional diesel truck, but an MIT study of the company's delivery fleet has found that the electric vehicles are 9 to 12 percent less expensive to operate. Payette says that they pay for themselves within four years. Moreover, the trucks are a huge hit with customers. So many people ask the drivers questions about the trucks that Staples printed up information sheets that can be handed out at intersections.

The drivers appreciate that the e-trucks' big battery packs can open the rear overhead doors for them, saving both time and labor. And they like the quiet. "They never want to go back to driving diesel," Payette says. "At 55 miles an hour, you can hold a conversation in the cab like you're sitting in your living room."

The company carefully selects the people who operate the electric trucks and spends a full day training them to maximize both range and efficiency. Once drivers begin their route, a qualified trainer rides with them for two days. After that, information-gathering systems in the trucks tell each driver how he or she is doing compared with others—"a little bit of peer pressure," in Payette's words.

Staples has been so pleased with the electric trucks that it has ordered five more. But Payette cautions that electric vehicles are tied to the utility grid, which, depending on your region, may rely on hydropower, natural gas, or coal. (Though they're still less polluting overall than petrol-powered vehicles.) "When you plug them in at night, somebody somewhere is creating that power," he notes. "If your electricity is being produced by a coal-fired power plant, you can't really take credit for zero emissions."