Moonshine Solar These small-scale window units are a little different and I’m really drawn to them. The designer started with few randomly placed cans in a housing and has since revised the design twice, incorporating some of the conventions common to the more sophisticated designs. I like the idea of having a portable "room heater" as opposed to – full-sized panel mounted on the side of the house for several reasons. • Less cost to build • No installation required • Portability -