Comparison of methodologies for TMY generation using 20 years data for Athens, Greece

The need of accurate Test Reference Years (TRYs) for simulations has been w ell recognised over the years. Various methods for deriving TRYs have been developed, but their final results can be significantly different. In this paper, the major methodologies reported in literature were applied to 20-ye ar hourly measurements of weather data from Athens, covering the period 197 7 to 1996, Seventeen TRYs were produced in total. The basis to select the " best" performing TRY includes meteorological criteria (inherent in the sele ction process used by each method) and comparisons of results from various simulations for typical energy systems (i.e. a solar water heater, a buildi ng, a large scale solar heating system with interseasonal storage and a pho tovoltaic system). Based on the results of each simulation er;exercise, a s coring system was developed and applied. The best performing TRY was found to be the one produced by a modified Festa-Ratto method. (C) 1999 Elsevier Science Ltd. All rights reserved.