Shariah, A.M.; Lof, G.O.G.
July 1997
Fuel and Energy Abstracts, vol 38-4, p. 243
The TRNSYS simulation program was used to simulate a thermosyphon solar water heating system with electric auxiliary heater. Location of the auxiliary heater, inside the storage tank or connected in series between the system and the user, was studied using the TMY meteorological data for Los Angeles, California. Simulations were performed for two different water-load temperatures (60 and 80°C) and for two types of daily hot water volumes (250 and 15O l). Four types of daily hot water consumption profiles were used in the present study. The results show that if water is drawn on a schedule corresponding to the Rand draw profile, the system operates with higher efficiency when the auxiliary heater is located in the storage tank than when the auxiliary heater is outside the storage tank. The increase in solar fraction depends on the load profile and volume, temperature setting, as well as the quality of the collector and the storage tank volume.
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