Responses (3)

JEFFREY PARKER May 14, 2020, 6:07 p.m.

Dear Emmanuel,

Thanks for your 2018 post. As you'd suggested, I'm following up to see how the hot air tubes in your slab floor are performing.

I'm keen to use PV solar to heat my radiant floors in an off-grid high thermal mass passive solar house I'm building on California's Mendocino coast. I'm leaning toward using an oversized PV solar array to run a heat pump to store and circulate hot water (rather than hot air) through our radiant flooring; the up-front cost for panels and inverters is higher, but it seems to me the falling prices of PV systems and heat pumps and the overall relative simplicity makes this worthwhile. I'm keen to learn from your experience.

Best thanks and warmest regards.

Emmanuel Cosgrove
Emmanuel Cosgrove May 19, 2020, 5:35 p.m.

Hi Jeffrey,  The air heated floor is nothing new and works fine, Legalett has been doing that for decades. Its the solar panels that are an experimental concept here but they still aren't on unfortunately. We hope to have that done shortly, and when they're on they will be used to preheat domestic hot water until they're needed for heating in the fall. So it will be next winter when we get an idea of how much heat the panels provide. We're pretty hopeful, and we will for sure update our pages when we have some figures.