[quote=Oxford]….He did show me this heating system that ran hot water through pipes in the slab….[/quote]
Oxford, sounds like a heat pump. I have some family members (in Europe) who are fanatical about lowering fossil fuel usage. Extremely well insulated house, cooled and heated by a deep heat pump, pumping cooled or heated water into flooring all through the house. Solar panels on top. I don’t think they use more than 50 euro a month in fossil fuels, through cold winters and warm summers.
But poor design or execution can lose most of the efficiency. I have to assume this person did a sloppy/cheap job of installation.
