New Holland Agriculture’s NH2 hydrogen-powered tractor won the prize for innovation at the SIMA Show in Paris in February. The NH2 is a key element in New Holland’s Energy Independent Farm concept, which aims to free farmers from the cost of buying fossil fuel and let them achieve fuel autonomy. Joe Spencer reports.
Based on the popular New Holland T6000, the experimental NH2 tractor can perform the same tasks, operates virtually silently and emits only water. It generates electricity using compressed hydrogen in automotive fuel cells.Vehicles like the NH2, running on hydrogen, have been in development for years. Battery-driven vehicles are efficient only in a stop-and-start cycle and take a long time to recharge, while disposing of batteries, which lose efficiency over time, is an environmental issue.
However, hydrogen fuel cells have a long working life and energy-dense compressed hydrogen can be stored in tanks for long periods, allowing the vehicle to be refuelled quickly.Hydrogen use to date has been hampered by availability and distribution problems. But New Holland’s Energy Independent Farm Concept envisages farmers producing their own compressed hydrogen from water using an electrolysis process, or directly from methane from burning waste or biomass. The hydrogen would be stored on-farm in an underground tank. This plan is particularly feasible for farmers as tractors, combines and implements usually travel short distances compared to cars or trucks.
A spokesperson for New Holland says, “Farmers have the space to install alternative electricity generation systems such as solar, wind, biomass or waste plants, and store that power as hydrogen. Apart from the environmental benefits, this would let farmers become energy independent and cut their fuel costs, a significant proportion of their operating costs.” |fw
Possibly the ultimate ‘green machine’
In the NH2, the engine and diesel tank have been replaced by fuel cells driving an electric motor and a vessel to contain compressed hydrogen. Emily Padfield of Farmer’s Weekly UK saw it at a preview in Turin, Italy. “In the cab, the tractor is eerily silent,” she reports. “The usual vertical exhaust pipe is gone too. A small pipe under the cab lets out the water, the only byproduct of the fuel cell.”
Emily explains the fuel cells work a bit like a giant battery, with a pair of electrodes surrounded by an electricity-conducting solution. Hydrogen (stored at 350 bar pressure in a tank) is passed over one electrode, and oxygen (from the air) over the other. The current generated is transferred to two electric motors. One drives the tractor and the other runs the power take-off and auxiliary services.
The NH2’s fuel cells generate 90kW and send the power, via a splitter, to all four wheels. There’s no gearbox or clutch – speed and power are controlled by putting more or less electric power into the motor. To reverse, one reverses the polarity to the fuel cell terminals.
