Read the article. It has a composting toilet, uses skylights for daylight illumination and has solar panels for electrical needs. Doesn't seem to use it for refrigeration though, which seems limiting.
vacation home, many cabins in the woods I grew up visiting were very basic, you were lucky to have a well let alone electricity.
I live in a similar-ish situation where I live on a narrowboat in London. I have a solar panel for electrical needs and I run the boat engine once every few days during the winter. For refrigeration, I've got a 12v fridge but many people I know use gas fridges. Fridges use up an amazing amount of power. But the fridge is really the only thing I run off electricity - occasionally charge up my laptop and charge my phone off the 12v supply. But yes, my boat batteries are pretty much there only for the fridge.