solar heated radiant flooring

[The Sun]

I saw an article in Solar Power magazine that used a solar thermal system built into a storage building wall to heat the homes radiant flooring.  It was pretty cool and easy to do, my question is, would this type of system be usful here in Austin.  We don't get too cold here but having a constant temperature running through the floor would provide all day and night heating to reduce having to have heat on if at all.  Any thoughts?