Clarkson, May, and the hobbit, just put the Genny in the back of their electric van,I have found the "solution"
I read of someone that restored an old trolley bus. To power it, he tows a trailer with a diesel generator. It is still legally classed as an electric vehicle, and he legally uses red diesel to power the gennie.
So the solution to the range issue is tow a trailer with a diesel genny running. Not even any emissions test needed.