Abstract

Lighting conditions in buildings and efficient use of solar energy are a subject of considerate attention in order to provide sufficient living comfort and to reduce the energy use. For this reason numerous methods and techniques, practical and theoretical, have been developed. In this paper a theoretical approach to modelling of the indoor lighting conditions is proposed, based on fuzzy black-box modelling. The presented model is able to estimate indoor illuminance levels as its outputs, by using measured external conditions as its inputs. The model can be used to study the influence of both controllable and uncontrollable variables to the indoor lighting conditions, such as weather, time of the year, blinds position, electric lighting and others. Furthermore, using the above model studies on control design can be performed in order to obtain algorithms for maximal use of the solar energy and to minimize the energy consumption. The study has shown that a fuzzy illuminance model can estimate the indoor illuminance levels comparable to the measured data. Small error measures show that similar modelling approach can be used in order to integrate the proposed model into other environments and can further be used for simulations on indoor lighting comfort, control design or modelbased control.