Microwaving ruins the skin for me, but does work much faster at least. A small toaster oven / convection oven might be a good trade off, and pressure cooker can do a good job too.
I'm not very up on the details of electricity prices, as I live in a place where it's cheap, but using a tiny air fryer to cook the sweet potatoes suits me just fine. Both are wrapped in foil and cut into chips or cubes. Kids love it for breakfast.
