Energy saving by compensation of daylight deficiences in buildings

The exploitation of the daylight in the illumination of the offices is one of the possibilities of the electrical energy saving for lighting. The paper presents the calculations performed in order to estimate the possible savings in Polish climate. The amount of energy consumed by artificial light sources for an exemplary office is taken as a reference. Power demands together with energy consumption for the daylight deficiencies compensation are calculated using the solar radiation measurements from September 2009 in Łódź, Poland.