Most truckers idle their engines while they take a nap, in order to keep the engines warm and the A/C running in the cab. CNN reports that some drivers have devices that cool off the cabs without having to run the engine, but those devices either use batteries that eventually wear out, or they use fuel on their own which pollutes the atmosphere. Webasto, a trucking equipment vendor, found a different solution.

The company's BlueCool system is essentially a 300-pound black box that sits on the truck's frame rail. "As the trucker drives, the system sends refrigerant through a matrix of graphite and a water/glycol mixture inside the box, creating blocks of ice," the report said. "When the truck is stopped, the driver turns on an air handler that circulates coolant around the ice and blows cold air from the unit into the bunk area of the cab. The fan and circulation pump use only 3.5 to 10 amps from the truck's battery" so as not to drain it prematurely.

The result? No emissions, no fuel used, and a cool cab for up to 10 hours. The system costs a whopping $5,500, but that pales in comparison to the EPA's estimate that said the average trucker wastes 2,400 gallons of fuel while idling per year—that's $9,600 at current prices.