Performance Model for Water-in-Glass Evacuated Tube Solar Water Heaters

A transient model of the performance eof water-in-glass evacuated tubular solar water heaters is presented. The model uses measured optical and heat loss characteristics of the evacuated tubes and a new thermosyphon circulation correlation for single ended evacuated tubes. The model is used to predict the performance of typical water-in-glass evacuated tube solar water heaters for a range of climatic conditions.