Solar panels are mounted on a building at each storey, at a level between the windows of adjacent storeys, and on the building roof. The panels may be photovoltaic and produce electricity for use in the building or distribution exterior of the building. The panels may heat an air stream which provides heating for rooms. Hot water may be produced in the panels, for use in central heating or for hot water consumption. Hybrid solar panels may be used which combine the above features. The panels may be positioned at a sloping angle to the building. Advantageously, in use the panels may provide shade to the building windows to reduce the solar radiation incident thereon.