Abstract
Solar and sky radiation falling on a tilted surface in Tokyo was calculated on the basis of sunshine recording data by use of the formulae proposed by PAGE. The results were compared with the observed global radiation and turned out to be in good agreement.
The efficiency of the radiation collector was discussed as a function of the sloping angle of the plate. It was concluded that the maximum efficiency is to be obtained by a plate of a slope lower by several degrees than that of the latitudinal angle itself. The order of magnitude of that difference proved to be 1% or so.
