Simple Conversion Method for Determination of the Global Illuminance from Satellite Images

Abstract

To better utilize natural sources in the performance of buildings during whole year the availability of detail data in time and for specific location plays key role. Such data offers ground measurements or databases of satellite images. Establishment and operation of CIE IDMP ground stations is quite expensive and there are a few active stations on the ground at this time. To study of irradiance availability in specific locality the data describing relevant local radiative conditions are needed. For this reason the satellite images offer sufficient information. The first part of this paper is focused on short introduction to the remote sensing and the Heliosat method. In the second part are presented results of the solar irradiance availability on the horizontal plane and their time changes based on the processing satellite images. The illuminance and irradiance data obtained at ground CIE IDMP station in Bratislava were used to proposed verify model for estimation of the global illuminance from irradiance. Cities Bratislava and Brno are relative close with distance 130 km and similar daylight climate of Central European climatic zone, therefore can be assumed that data from CIE IDMP station Bratislava can represent relation between photometric and radiometric variables and daylighting changes in Brno.