Abstract: Evacuated solar panel (1) comprises a frame (2) carrying spacers (3,4) crossing one another and one or two transparent walls (10, 10a) connected to said frame (2) and defining with said frame (2) an evacuated closed chamber (11). The chamber (11) contains the longitudinal and transverse spacers (3,4) and an absorber (14) comprising a plurality of absorbing panels (14a, 14b) each connected to a cooling pipe (15) welded to the frame (2) at both extremities. The longitudinal spacers (3) are in contact with the transparent wall (10) to support it against the ambient pressure, while the transverse spacers (4) support the longitudinal sides of the frame (2) against the ambient pressure and are not in contact with the transparent wall (10), so allowing the absorbers (14a, 14b) to cover the whole length of the panel (1) without interruptions.

Abstract: Device for vacuum tight soldering together a perimeter metal coating (5) of a transparent wall (4) to a perimeter metal frame (3) of a holding structure (2) of an evacuated solar collector (1), in particular a flat solar collector, said collector comprising a joining ribbon (6), preferably a soft metal strip or ribbon, in particular a lead and/or copper strip or ribbon, which is adapted to vacuum tight seal the gap (7) between said transparent wall (4) and said metal frame (3) and which is adapted to be soldered, in particular soft soldered, to said perimeter metal frame (3) and said perimeter metal coating (5) of the transparent wall (4), said joining ribbon comprising a soldering alloy, said device comprising heating means (24) for heating: a first part (5A) of said transparent wall (4) comprising at least a portion of said perimeter metal coating (5), a second part (3A) of said holding structure (2) comprising at least a portion of said perimeter metal frame (3), and said joining ribbon (6) to at least the