Dutch Fendt importer Agromec, together with Electric Construction Equipment, has ‘electrified’ a Fendt 700 Vario by fitting an exchangeable battery on the front linkage. Our friends at Trekker magazine in the Netherlands have been for a first look.
How can the energy from 400 litres of diesel be replaced by an all-new ‘emission-free’ driveline? This was the intriguing challenge given to Mart van der Valk, of Electric Construction Equipment (ECE), on behalf of Dutch Fendt importer Agromec as well as the construction company Van Wijlen.
Hydrogen or battery?
One possible option was hydrogen. However, this is not only currently expensive and has a limited energy density, but the required fuel cell is also expensive.
The second option was a battery pack that could be installed on the tractor. Yet this also proved to be impractical, because a battery capable of providing the same run time as 400 litres of diesel would weigh around 15 tonnes. Enter the exchangeable battery that could be mounted on the front linkage, the exchange taking only a matter of minutes and allowing work to continue. So, if enough batteries are available, you can continually work with electricity. But we’re getting ahead of ourselves. Let’s start at the beginning of this project’s story.
720 Vario as the starting point
Agromec used the Fendt 720 as the basis for its electric tractor. All of the components that relate to the diesel engine are removed: the tanks, radiators etc and, of course, the exhaust stack. Then a permanent-magnet Danfoss synchronous electric motor is installed. Measuring just 45cm by 65cm, the vibration damper fits into the chassis frame of the tractor.
The 800 volt unit can deliver a nominal 300kW/410hp+; however, this was tuned down to produce 150kW/200hp to match the performance of the Deutz diesel burner and not overwhelm the Vario transmission.