Experimental regression model to predict natural lighting levels and energy savings in buildings

A. Jiménez-Valle, M. Varo-Martínez and R. López-Luque



This paper presents a model to estimate the values of natural lighting that can be registered in interior spaces with light pipes, as well as the savings percentage that may be obtained by using
this technology. The lighting data obtained with an experimental prototype on scale of a teaching space at the University of Córdoba - where light pipes have been introduced -, together with the irradiance data registered in the radiometric station of the Applied Physics Department (University of Córdoba), have allowed the development of a regression model among the levels of natural
lighting, sun elevation, and global and diffuse solar irradiance. The phenomenon behaviour has been simulated for a year with this regression, which has resulted in large time intervals with
natural lighting levels above the minimum threshold recommended for teaching spaces.

Published in: Renewable Energy & Power Quality Journal (RE&PQJ),Vol. 1, Nº. 14
Pages:537-541 Date of Publication: 2016/5/20
ISSN: 2172-038X Date of Current Version:2016/5/4
REF:384-16 Issue Date: May 2016
DOI:10.24084/repqj14.384 Publisher: EA4EPQ

Authors and affiliations

M. Torres Roldán, M. Varo-Martínez, R. López-Luque
Research Group on Physics for Renewable Energy and Resources. University of Córdoba. Spain

Key words

Energy efficiency, natural lighting, light pipes.


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