Tesla’s design [for Wardenclyffe] used a concept of a charged conductive upper layer in the atmosphere, a theory dating back to an 1872 idea for a proposed wireless power system by Mahlon Loomis. Tesla not only believed that he could use this layer as his return path in his electrical conduction system, but that the power flowing through it would make it glow, providing night time lighting for cities and shipping lanes.

It’s a very Victorian / Steampunk idea that is also kind of horrifying. It’s working off theories of what electricity “is” that we now know aren’t accurate, but if you try to scale them to actually working every building and tree and person is now a lightning rod.