Manufacturers of implements have long wanted to replace belts and shafts with electric motors powered from a socket on the tractor, rather than a mechanical power take-off (PTO).

John Deere appears to be the first major manufacturer to make a stab at doing so with the announcement of its eAutoPower system to be made available on the 8R 410.

Ditching the weight

The advantages are numerous, the biggest being that power sapping mechanical drive trains are done away with altogether.

Not only do they waste energy but are heavy and often a machine has to be designed around them, rather than vice versa.

Belts and shafts have a good deal of weight and can induce torque loadings on frames that need to be built to cope with them.

Strategically sited electric motors orientated in whichever direction is required are a lot lighter, and require less reinforcement to the frame.

Connecting a cable is easier and cleaner than attaching a PTO shaft

Lighter implements are cheaper to build, resulting in lower priced machines that are better for the soil and more economical to pull.

Electric power reduces costs

Constraints placed on design by the need to route power trains are also lifted.

Something of a small revolution in how machines work might be expected if there need only be an electric motor placed to optimise the function, rather than the function being compromised by the need for a belt or shaft to drive it.

Belts, bearings, chains and shafts all have inertia which is another power drain; they also lose energy through friction, energy that electric cables mainly preserve, although they are not perfect.

Further benefits of electric drive to implements will no doubt surface as the machines are developed, yet it is an already established mechanism that John Deere has chosen to work with first.

Powered trailers revisited

Powering trailer axles from a tractor’s PTO has been around for many years so the concept is tried and trusted.

John Deere has partnered with Joskin in building a slurry tanker with power provided to two of the three axles.

John Deere electric PTO transmission
The two alternators sit immediately behind the transmission

At the tractor end, the JD 8R 410 has two alternators being driven off the rear of the transmission. These can supply up to 100kW of power to two sockets mounted at the rear.

The company claims that the electrical system completely replaces the hydraulic components with an electric power path.

However, on the tanker, the power is fed to a single electric motor which then drives the two axles via standard shafts and differentials in the conventional manner.

John Deere is naturally claiming that electric drive to implements is a huge leap forward, and it certainly has that potential, but with this present arrangement, the company appears to be somewhat cautious in its approach.