Promotion the Efficiency of Thermosyphon Solar-Electrical Water Heaters using a Daily Scheduled Timer Key

Author

Abstract

The solar radiation energy is one of the clean, essential, and renewable resources for the future. Iran, having 300 annual sunny days, has such intrinsic potential, and thermosyphon solar-electrical water heaters (TSEWH) are the simplest solar-thermal convertors. Despite their unique merits, they cannot supply hot water for domestic applications during a cold period. Thus so an auxiliary backup system such as an electrical resistance heater (electrical element) is required. The reduction of consumed electrical energy by electrical element leads to not only a decrease in the electrical network load but also to an enhancement in the efficiency of solar water heaters while speeding up their application in building sectors. A careful scheduling of the electrical element circuit via a timer key (timing mode operating) leads to a reduction in the auxiliary portion compared to the case where the circuit is to be activated permanently (continues mode). The field results imply that the implementation of the timer key to TSEWH has been considerable during the cold period and reduced the consumed electrical energy as much as 700kWh yearly while having promoted its annual efficiency from 46% up to 67%. 

Keywords


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