A current touch a wire is never without resistance unless chilled to super conductivity temperatures, close to zero Kelvin.
Whenever there is resistance there is heat.
Besides, a clever mofo could possibly make a microwave oven from the EM radiation
I'm talking about wires behaving as antennas.
Antennas also become warm.
A microwave oven is one high powered antenna, although there is only gibberish being sent to the product.