Are e-tractors practical?

Even when purchase prices come down, will it ever be practical to run a big battery powered 4×4 to replace your Versatile?

We will see bigger battery tractors than we have now, for sure, but they will be very expensive until battery costs comes down. For now, Europeans can buy a 70-horsepower electric tractor with a 100-kWh battery and five-to-six hour run time, but the cost is more than US$120,000. You need to be a highly motivated environmentalist to justify that purchase.

The e-advocates say that in time, technology and manufacturing efficiency will overcome the cost factor, but battery run time may remain a deterrent.

The other negative factor is that so many e-tractor projects tie themselves to “free solar power.”

And that might be the fatal flaw in their logic. The e-tractor is one topic for discussion. Charging the battery is a distinctly different topic.

It’s an unfortunate coincidence of nature that solar panels for re-charging tractor batteries can turn sunlight into electrical power only while the sun shines. Those are the same hours your e-tractor should be in the field working.

With most e-tractors now in production, a battery charge lasts only four to six hours, approximately half the number of daily hours the tractor works during a busy season. If you have two battery packs, one can power the tractor during the morning shift while the other pack is on the solar charger. If the first battery runs down before noon, you can always send your diesel tractor back to the yard to pick up the fresh battery.

Fine, but what if you get two weeks of cloudy weather at seeding time? Your economic model based on “free energy” goes out the window, especially if you start paying the grid a dime per kWh to charge your batteries.

“Grid” is the most dreaded word for followers of sun power. The prudent e-tractor buyer will not tie his return on investment to “free energy” but instead buy for the other benefits, of which there are many:

  • Electric motors last longer than diesel.
  • Their controls are much simpler and they put the power to the ground more efficiently.
  • They’re quieter.
  • Initial investment is lower.
  • They don’t pollute.

Some farmers feel the environmental factor is a red herring when it comes to diesels in agriculture.

People who have visited the factories often notice rows of ag implements with no emission control systems. These are machines built specifically for export to developing nations.

But doesn’t the Earth have only one atmosphere wrapping around the whole big ball of dirt? Is it fair to North American farmers that producers in other parts of the world can buy lower-priced higher-efficiency machines?

There’s another consideration. The ratio of farm diesels to over-the-road highway diesels is incredibly skewed, yet off-road diesels are subject to the same standards as highway tractors. The ratio becomes even more off-kilter when you compare the annual number of hours for a farm diesel to the annual number of hours for a highway engine.

It’s not likely many farmers will buy an electric tractor for environmental reasons. When the e-tractor makes economic sense, the orders will start to flow.

The other motivating factor in favour of electricity might be reliability in the field. Farmers get their hackles up when they talk about their brand new tractor, sprayer or combine going dead in the field because of a glitch somewhere in the ECU or any related device.

E-manufacturers will go a long way toward electrifying farmers’ equipment lineup if they can prove their products are more reliable than current state-of-the-art diesel systems.

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