re: frugal heating this winter??
8 oct 2004
>this system was developed by horazio barra in italy and originally used as a
>passive solar heating system. floors of reinforced concrete are used with
>embedded channels utilising hollow concrete blocks. outdoor air is blown
>through the channels...
in the passive version, indoor air thermosyphons through an air heater (eg
a layer of glazing over a dark wall) outside the insulated wall of a house
and rises up and flows through concrete ceiling channels from south to north,
then drops from the ceiling into the room and flows back south through the
room to the air heater inlet. the upper air heater opening might have a
passive plastic film one-way damper, or david delaney's flow organizer. the
ceiling might have a low-e coating beneath to store more heat in warmer mass
without overheating the room. a hydronic floor above the ceiling might add
more thermal mass and control.
>sounds a lot like kachadorian's solar slab...
that won't work passively.
>the swedish developed termodeck system uses the slab as both a structural
>component and also a means of ducting ventilation through the building
>through oval or round shaped holes within the concrete structure...
that won't work passively either, from the web description. it warms
outdoor vs indoor air with fossil fuels, and it doesn't use air heaters.
>with the termodeck systems the slab temperature is very close to the room
so the slab stores little heat.