seen some details of a new system which will be avialble in uk next year 48v underfloor electric ,powered by solar PV --and tesla battery system --anyone got more info ?

Using PV for electric resistance heating doesn’t usually pass the economic test as you need a lot of electric with resistance heating and PV electric tends to be relatively expensive and better used. However, if you have a situation where you don’t need too much heating (e.g., a well insulated/sealed small house), perhaps it might make sense.

A guy named electrodacus analyzed the numbers and went with PV solar, resistance heat and thermal storage (lots of concrete).