Case Construction Equipment's prototype hybrid material-handling excavator unveiled at Intermat is based on the elevated-cab CX210B. The prototype has the potential to reduce fuel consumption by up to 40%, with a substantial cut in exhaust emissions.
The hybrid system uses a diesel engine to power the hydraulic system for the boom and track drive, but the engine also powers an electric generator that in turn powers the slew motor and magnet. Under low-load conditions, the diesel converts surplus energy to electricity that is then stored in capacitors. As the load levels increase, the electrical system provides additional power, keeping the diesel engine speed down and reducing fuel consumption and noise levels.
Scrap handling often means constant turning, and the electric swing motor uses less energy than a hydraulic system. Also, the energy created as the slew brake is used is collected and stored in the capacitors.
The electromagnet generator is also connected to the hybrid drive, making use of the energy stored in the system. By powering the magnet through the electrical system, a 25% fuel savings can be achieved, with the other 15% coming from the electric swing system.
As the fuel consumption is reduced, so are the emissions, and Case is working to find ways to meet upcoming regulations around the world, including the Tier 4 Interim and Tier 4 Final levels.
All current engines produced by Case are approved for biodiesel use. Most machines can be used with B20. Nevertheless, low-sulfur diesel will remain the primary fuel used worldwide, according to Case. To meet this demand, Case, in cooperation with Fiat Powertrain Technologies, is developing new diesels to meet Tier 4 regulations by 2011, which apply to engines producing more than 130 kW (174 hp).