Somehow the electric connection had fallen out of the bracket. Had to disassemble and reassemble some bits but really, maybe 3 months of mild irritation and in the end it took maybe 20 minutes to fix. There’s a lesson I don’t want to learn somewhere in there…
It uses electricity to make heat. That’s the one conversion where you can expect approximately 100% efficiency.
Modern stoves have fancy safety features and a flat glass top to make it look nicer. I don’t think the efficiency has gone up in the past 50 years.