Hybrids aren't just for eco-conscious soccer moms.
General Electric on Tuesday said that it has tested a hybrid version of a haul truck, the kind of giant dump truck that's used at a mine or to haul away mountains of dirt.
The system works just like a Toyota Prius, more or less. The engine feeds electricity to a battery that runs the drivetrain. During braking, the spinning wheels act as a generator for the battery.
The batteries in the hybrid off-highway truck is the same sodium-based battery used in GE's locomotives, according to the GE Research blog.
The hybrid haul truck wasn't just announced in honor of Earth Day.
Rising fuel prices are pushing truck manufacturers to adopt more efficient and clean technologies.
Volvo is developing a range of Mack trucks with the goal of making them carbon neutral. A hybrid Mack dump truck can save between 25 percent and 30 percent on fuel costs.