If you don’t already have an indoor wood burning stove that heats your water, this is a great way to get unlimited ‘off the grid’ hot water.
This system is super efficient, heating the water with minimal fuel. It is also relatively straightforward to build. I also think that with some modifications you could also cook on this as well.
All in all this would make an excellent permanent addition to a homestead. It could also be built and used in an urban setting as well.