Foam insulation/shading system for transparent structures

A periodically shieldable solar structure comprising at least one cavity formed between a pair of light transmitting members, and a foam insulation/shading system for periodically filling said at least one cavity with degradable foam, said foam insulation/shading system comprising an air supply pipe connected to a source of low-pressure air and extending along said at least one cavity, a foaming solution supply pipe connected to a source of foaming solution and extending along said at least one cavity, and a series of axially spaced-apart foam generators mounted within said at least one cavity and distributed therealong to provide multiple discrete points of mixture for the air and foaming solution as well as multiple foam outlet points within each single one of said at least one cavity, the foam generators being located in an upper end portion of the at least one cavity, the low pressure air and the foaming solution being separately supplied to said foam generators via said air supply pipe and said foaming solution supply pipe to locally produce the foam at each of said axially spaced-apart foam generators, each of the foam generators having a body defining a chamber, the chamber having an outlet provided with a screen, each foam generator further having an air inlet configured to provide for a flow of low-pressure air from the air supply pipe to the chamber and at least one nozzle connected to the foaming solution pipe for directly spraying the foaming solution onto an inner face of the screen such that foam is generated by the low-pressure air released through the screen, the axis of the at least one nozzle intersecting the screen.