[Greenbuilding] Barra system

[Chris Green]

Paul Newby wrote:
> Hi all,
>
> Anyone know anything about the 'Barra system' - a
> brief description at http://en.wikipedia.org/wiki/Barra_system ?
>   
An interesting idea. Thanks for the link.

This seems to be a descendant of a similar idea promoted by a solar 
research organization,IIRC, in France in the 1970's. Their system had 
glazing over top of concrete or other massive trombe walls which had a 
black painted surface. These assemblies didn't cover the entire wall, 
but looked somewhat like blacked out windows.

Barra's system seems to have some distinct improvements to be noted. 
However, my preference would still be to choose a vacuum solar tube 
system as a collector since the heat-carrying agent is a liquid, and one 
can use a liquid which will not freeze if there's a chance of that 
happening.

Cheers,

Chris Green.