Self-supporting, modular prefabricated radiating panel

A prefabricated, rectangular, self-supporting, radiating panel (P) comprising two opposite long sides and two opposite short sides and comprising a sandwich structure formed by a one-piece layer of plasterboard (1) and a layer of heat-insulating material (2), said plasterboard layer (1) incorporating, internally, pipes (3) for a working fluid, end portions of said pipes emerging from a side of the panel, a plurality of said pipes (3) being each housed in cavities arranged in a coiled outline on the side of the plasterboard next to said heat-insulating material (2) and in adjacent modular zones (6) of the panel and each pipe forming an independent hydraulic circuit, said zones (6) being rectangular and comprising two opposite short sides and two opposite long sides parallel to said short sides of said panel, said panel being a single, stand-alone panel, said zones (6) being separable from one another so as to provide panel parts of different sizes.