Britesea
Sustainability Master
@Britesea, can you explain a little more how the Excalibur design lends itself to conversion to solar power if electricity isn't available. I don't think I followed you from the picture you posted.
The picture shows some cans in a glass fronted box- painted black to increase heat. The air flow comes in at the bottom and rises to the top due to convection. At the top, the heated air flows into a box and circulates around the trays. I believe that by simply making a different front closure to the Excalibur, you could create a path for the heated air to go into the Excalibur box instead of the pictured one. If one could add a small solar-powered fan at the back, it would work even more efficiently.