@bsmall2 @Iragersh interesting about the wood. An earthship may not be "the thing" for your place in japan. but you could use many ideas to make a passive house or a high efficiency space (of an appropriate size). I mean renewable energy may be wind or water and not solar in your area. And water collection looks different everywhere too. Perhaps a composting toilet. And reducing your car use, like mentioned, and increasing things like walking and using a bicycle too. Having a #LowImpact on the earth is a social thing too, so in this case how we use what we use how we take from the earth and how we give back. how we use language to oppress others (even unintentionally).
I suggest finding the elders, whose people have lived in that place for generations. Ask them questions. Ask their opinion. They will be able to guide you to the best options for your place. they will know the #HistoryOfPlace better than any book and will be able to tell you what to think about and be cautious about. perhaps it is piled up logs in a modified earthship, and perhaps there is a design that hasn't been commercialized yet that would be better.