An evaluation of radiance based simulations of annual indoor illuminance distributions due to daylight

This paper presents a new, accelerated method based on GD\OLJKWFRHIILFLHQWV according to Tregenza [1] to calculate cumulative annual indoor illuminance distributions. Simulation results are compared with five RADIANCE based daylight simulation methods including the daylight factor method [2], ADELINE 2.0 [3] and ESP-r version 9 series [4]. An explicit calculation of the indoor illuminances under all annual hourly mean sky luminance distributions serves as a reference case against which the other methods are tested. The analysis of the results reveals that the new method exhibits the highest accuracy and lowest simulation times for all considered building geometries. The quality of an annual daylight simulation is not necessarily coupled with the required simulation times but depends on the underlying sky luminous efficacy model and whether the method considers the hourly mean direct and diffuse illuminances for each time period explicitly.