Wondering about cob vs earthship. I suppose the food growing would be one major difference, but what else? I've seen a lot of great cob living spaces and I'm sure it's possible to combine - earthship construct with cob styling
fireplace surrounded by sculpted cob - a mixture of clay, sand & straw - that absorbs the heat from the fire and stays warm long after the fire is done burning. Much more efficient than a regular fireplace (which can have a net cooling effect).