A solar receiver (2) comprises a housing (4) defining a receiver chamber (12) and an aperture (14); a window (16) mounted in the aperture (14); at least two inlet means (17) axially spaced from the window (16) and positioned at different distances therefrom for the injection into the receiver chamber (12) of different flows of workind fluid; an outlet means (18) for the ejection of the working fluid out of the receiver chamber (12); and absorption control means for the provision of the different flows of the working fluid with different capability to absorb solar radiation
