Hi Raymond,
I think it would be an interesting idea, but I am concerned that it might be costly to put in and costly to run. I also worry that it is not super efficient as it would likely release heat in both directions.
If you are looking for something electric, they make electric radiant panels that can be mounted to the walls, ceilings, or floors. It uses electrical resistance to create heat. If you put them on the north wall with insulation between the panel and the outside, it would keep the heat inside.
There are also hydronic radiant panels that can be mounted the same way. It's just pipes with
hot water running through them running through some sort of mass. There are commercial ones and diy ones. I like the idea of
water myself, as it is easier to use a renewable method to heat the water, with just a small amount of electricity for circulating the water. Again, it would give you the radiant feel, with much less work after it was installed.
Both of those options would be much easier and still give the feeling of a mass heater.
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