Abstract: Heat exchanger device comprising a tubing for receiving and delivering a heat transfer fluid; a phase-change material, PCM, encompassing said tubing; a plurality of cells receiving the phase-change material, PCM, such that the flow of the heat transfer fluid in said tubing causes each cell PCM to change phase gradually in the direction of the inlet to the outlet. The cells may be closed cells or open cells, the tubing may comprise fins and the exchanger may comprise an external tank for containing the PCM. The heat exchanger may comprise a second tubing for receiving and delivering a second heat transfer fluid, wherein the second tubing is connected to the PCM cells and/or to the fins of the first tubing, such that heat is transferred between the first tubing and the second tubing as each cell PCM gradually changes phase.

Abstract: A system for heating a work fluid and for air circulation comprises a plurality of collectors fitted top-to-top in one or more columns, such that air ducts of the modules constitute a single duct along a column, wherein the solar collector comprises: one solar radiation planar absorber with one anterior face exposed to solar radiation and another posterior face affixed to the work fluid piping; one duct for exchanging heat with the planar absorber via the air duct which has its air inlet and outlet on opposite tops of the solar collector. The system can additionally comprise a descendent air duct to collect air from the upper part of the building and to supply air to the lower side of one or more columns of the facade.

Abstract: A system for heating a work fluid and for air circulation comprises a plurality of collectors fitted top-to-top in one or more columns, such that air ducts of the modules constitute a single duct along a column, wherein the solar collector comprises: one solar radiation planar absorber with one anterior face exposed to solar radiation and another posterior face affixed to the work fluid piping; one duct for exchanging heat with the planar absorber via the air duct which has its air inlet and outlet on opposite tops of the solar collector. The system can additionally comprise a descendent air duct to collect air from the upper part of the building and to supply air to the lower side of one or more columns of the facade.