Fascinating idea, though light on technical detail about efficiency, etc. Like what's the cost per BTU compared to gas boiler? Here's an article from the Guardian on this device: <a href="https://www.theguardian.com/environment/2021/mar/16/first-microwave-powered-home-boiler-could-help-cut-emissions" rel="nofollow">https://www.theguardian.com/environment/2021/mar/16/first-mi...</a><p>"The Heat Wayv unit is the same size as a gas boiler and has 10 metres of pipe coiled inside, which is heated at multiple points along its length. The microwaves are produced by solid state components, which can be tuned specifically to heat water and better targeted than the magnetrons used in microwave ovens...They say the boiler is 84% efficient in converting electricity into hot water...The ability to be dropped in as a replacement for a gas boiler is a significant benefit, they said, though they would use more electricity and therefore cost more to run than heat pumps and gas boilers."<p>Seems to be billed as a solution for domestic potable hot water and radiant heat, which probably means it's scarcely above 80F. I don't know what that means for traditional hydronic systems that run at 180F.