The award-winning prototype of a Landini hybrid tractor demonstrates the potential for improved fuel economy and environmental credentials.
With a strong global reputation for toughness, performance and operator appeal, the Landini Rex family of specialised tractors has carved out an enviable World-wide position in the market for mechanised power in vineyards, top fruit and orchards.
Landini manufacturer Argo Tractors aims to secure and develop that position for future generations with research into new technologies that can reduce operating costs and the machine’s impact on the environment, and further improve that operator appeal. According to Giovanni Esposito, Innovation Director: “We have been engaged for some years in an electrification program for our specialised tractors, establishing a new culture, acquiring new skills and creating specific processes within the company to encourage innovation.”
Argo Tractors’ latest research project has borne fruit with the unveiling at the EIMA show in Italy of a prototype Landini REX4 orchard tractor with plug-in hybrid power. “Included in this new vehicle are technologies for optimising mechanical systems, reducing noise levels, recovering energy and intelligently managing power flows in the various electrical devices,” explains Giovanni Esposito.
The Landini REX4 Full-Hybrid prototype is powered principally by a 55kW (74hp) diesel engine as installed in the current range of REX4 specialised tractors, which extends to 82kW (112hp) in various width and height configurations to suit different applications and vineyard/orchard growing systems.
Unlike the standard tractors, however, the hybrid power version also has a combined electric motor/generator within the driveline, producing a nominal output of 50kW (67hp) and up to 65kW (87hp) peak, which can either be used on its own or in support of the internal combustion engine.
The regular mechanical transmission is retained, although the electric motor is used for reversing and is selected by the usual shuttle lever beneath the steering wheel. In Full Hybrid mode, the electric motor adds 25kW (33hp) to the diesel engine’s output to assist with power-demand peaks – such as moving off with a heavy trailed load or with high-draft soil engaging equipment.
While in Full Electric mode, the Landini hybrid tractor can operate for approximately two hours on quiet, non-polluting electric power alone. The energy storage battery is topped up when the diesel engine is running thanks to a generator incorporated with the electric motor; a plug-in charging facility enables the battery to be fully recharged when necessary.
“Management software monitors and regulates the power flow, identifying the optimum operating point of the two propulsion systems, and also manages battery charging,” says Mr Esposito. “In a series of tests to validate what has been developed, our conventional and hybrid tractors were compared in a simulated a transport driving cycle, with different loading conditions and speeds explored. The results showed a consistent and significant reduction in fuel consumption of around 14% for the hybrid power combination.”
The appeal of being able to operate on electric power alone is particularly relevant in large glasshouses and polytunnels, and especially when working alongside a manual labour force, since there are no diesel exhaust fumes nor excessive noise. To realise this potential, the Landini hybrid tractor is equipped with a variable-speed electric motor to drive the steering and hydraulic system pumps, the latter operating the rear implement hitch and external hydraulic oil flow. Particular attention has been paid to minimising the noise generated by the hydraulic pumps and valves so as not to disturb the peace when running on quiet electric power.