More than 600 fleet managers and fleet stakeholders took part at last week's Green Fleet Conference & Expo, held Oct. 1-2 at the Phoenix Convention Center. Although this was the sixth year for the show, it was the first with a "truck track" designed for medium- and heavy-duty truck fleets.

The exhibition hall had nearly 70 exhibitors, and while there were plenty of interesting things to see, here are three of the most intriguing:

A purpose-built CNG truck

What is this Chinese-brand cab doing here? Turns out it's one of the few non-American parts on a CNG truck assembled in Southern California by GreenKraft. Unlike most other natural-gas vehicles, it's purpose-built, not a conversion, using a powertrain from GM. The 16,000-pound-GVW truck offers about 9,000 pounds of cargo capacity.

The maker says it has the largest CNG fuel capacity in the medium-duty market. The 60 diesel-gallon equivalents give it the same range as a standard diesel Isuzu, according to the booth representative from Ryder, which has ordered 20 of them with grant funding.

A way to fit more CNG in the tank

BASF is using chemistry to increase the fuel storage capacity of natural gas vehicles with something called "metal organic frameworks." My chemistry's a bit shaky (there's a reason I'm a journalist and not a scientist), but Raghu Bummaraju from BASF explained that in today's CNG tanks, the gas is less dense in the center. By putting pellets made of this MOF material, there's potential to store more CNG fuel in the same amount of space by making the storage of gas in the tank more uniform.

Researchers hope to get 10% to 30% range extension, but they're still in the first phase of testing and are looking for fleets for testing. At the show, they displayed a Kenworth T440 that's been upfitted with the system.

From-the-ground-up EV

This Boulder Electric Vehicle was one of the most unusual vehicles on display. Unlike most other electric trucks that convert existing chassis, this one was designed and built from the ground up as an electric vehicle.

American-built, it uses a 3-inch honeycomb aluminum frame for strength and crash resistance while maintaining light weight. All the electronics are housed in a single cabinet above the batteries, so there are no high-voltage wires strung about to worry about.

It has a top speed of 75 mph, and travel 100 miles on about $5 of electricity, according to a spokesman at the show. Charging takes about 10 to 12 hours. The company can work with body builders to put various types of bodies, such as stake beds, flatbeds, service-bodies, delivery vans, box bodies, etc.