FEW-DAY SOLAR-RADIATION CYCLES AND THEIR USE IN BUILDING SIMULATION

This article describes the use of simple solar radiation data in time-dependent simulations of passive solar buildings. Starting from monthly data for bright sunshine hours and mean ambient temperatures, sunny and dull day radiations on inclined surfaces are computed. These radiations can be combined into values for few-day cycles which are statistically typical of the radiation over an extended period. Several different building models are simulated over the few-day cycles. The auxiliary heating needed to maintain the building at comfort temperature over the cycles is extrapolated to give seasonal heating loads. These and computed temperature swings are compared with results from detailed seasonal day-by-day simulations. Generally the few-day cycles give accurate values for seasonal heat loads and temperature swings. A 6-day cycle has the most typical statistical properties and gives the best results.