Photo courtesy of Caterpillar Inc.

Cat's new hybrid excavator generated more than 300 patents.

Seeking to deliver greater fuel efficiency in its line of earthmoving machines, Caterpillar Inc. has unveiled its first hybrid excavator, the 336E-H. The technology will pay back in as little as one year, the company says.

With an operating weight of approximately 40 tons, the excavator cuts fuel consumption by 25% over its non-hybrid counterpart, the standard 336E, and 33% over the outgoing model, the 336D, Cat says. Measured in tons of material moved per gallon, the hybrid excavator is 50% more fuel-efficient than the 336D.

A hydraulic-hybrid drive is key to the fuel savings. It stores energy in the form of pressurized fluid, which builds up in accumulators as the machine swings in one direction. As the operator swings the rig in the opposite direction, the fluid releases, reducing strain on the diesel engine.

"The 336 excavator—a recognized industry-leading workhorse in our product line—made the most sense as our first choice for applying the unique hybrid technology," says Gary Stampanato, Caterpillar vice president, in a statement. Last month, Cat unveiled a supersized mining shovel that also runs on hybrid power.

The construction machine, unveiled near Peoria, Ill., on Oct. 16, will go on sale next February for March delivery. It also will be on display at the Bauma 2013 exhibition next April in Munich. Both the hybrid and non-hybrid versions will be available for sale next year.

Caterpillar was among the first to develop a commercially available hybrid construction machine. Its D7E crawler dozer, which uses diesel-electric hybrid power, went on sale in 2009. Cat's new fuel-sipping excavator generated more than 300 patents, the company says.