Energy program validation: conclusions of IEA Annex I

Abstract Computer programs for predicting the energy consumption of a building are providing architects and building services engineers with very valuable aids to assist them in the design function. The calculation of building energy flows is extremely complex, and so validation is a vital element in the development of any model. Under the auspices of the International Energy Agency, 23 computer program owners from 8 different countries collaborated in a joint R&D project to compare energy programs, both in terms of consistency between programs, and in considering the accuracy of these same programs in modelling the behaviour of a real building. This paper summarizes the major conclusions that developed out of the project, and gives insight into some of the most important aspects which need to be considered in the development of a reliable computer program.