Energy efficiency & IAQ aspects of the school buildings in Greece

The present article deals with the energy classification and the environmental evaluation of the school buildings in Greece. The energy performance of the school buildings, in relation to the normalized annual consumption for heating regarding floor area and climatic conditions, was rated using clustering technique (K-means algorithm) and an energy classification tool developed. The audited school buildings were classified into five energy categories. To investigate the potential for energy savings a methodology for the definition of the characteristics of the typical building for each energy class of the school sector has been developed using multivariate statistical techniques. It is based on a selection of seven variables that influence the energy performance of the building and has been mainly carried out using principal components analysis techniques (PCA). For the evaluation of indoor temperatures, the heating loads and the potential for energy conservation interventions, the typical buildings in each class have been simulated for a typical meteorological year, using TRNSYS. The measurements of indoor air quality concerned in concentrations of monoxide (CO) and carbon dioxide (CO2), as well as in the organic volatile compounds (TVOCs) in 83 classrooms. Thermal comfort conditions have been calculated using the indoor measurements of the meteorological parameters. The research has shown that school buildings suffer from important IAQ problems while their energy consumption and global environmental quality can be improved considerably. The conclusions obtained promote a general energy and environmental evaluation of the school buildings in Greece.