Not immediately viable, but much better for many applications: I’m imagining an agrovoltaic setup where the tractors use a pantograph to pull energy from an overhead line mounted off the solar panels. Effectively, it would be a trackless tractor-tram. Only a small battery would be needed for row end turnarounds and driving between fields. They already mostly drive themselves, so having the rows of panels to reference off of would actually simplify the navigation system substantially, and at that point you may as well add a pantograph and overhead line.