Solar wall heater

[Will Firstbrook WCB of BC]

Hi ,

I was just thinking about low cost ways of heating a cob building and
this idea came to mind. I would be interested in comments as I am not
even sure if it is a problem in the first place.

The idea is to use the sun to heat the exterior of the southern exposed
cob walls. This could be accomplished by imbedding some glass on the
southern exterior side of the structure and leaving a small air pocket
between the glass and the cob. The cob would be painted/stained/dyed
black for maximum heat absorption. This should transfer quite a bit of
heat into the cob depending on how big this glass is and how much sun is
available. If little sun is available the glass and air pocket provides
a little insulation for the cob. In the summer if it gets very hot,
shutters could be installed to minimize heat absorption; Or an overhang
could be designed to allow winter sun to heat the window yet shade the
window from the sun in the summer.

A variation of this could be to build  a solar oven into a south wall
near the kitchen with interior access.

Does this seem feasible, or even worthwhile? I know this is essentially
the passive solar way of heating the interior through the windows to
heat an interior thermal mass wall. But at certain locations it may be
desirable to not have a window to the interior.

Regards,
Will