Experimental investigation of a Scheffler reflector for the medium temperature applications

Abstract

This research problem reveals the experimental investigation at a pressure of 1.5 bar and temperature of 120°C for the medium thermal applications utilizing the four Scheffler reflectors with 16 m2 surface area each. The Scheffler collector associated with absorber plate of mild steel of size, 0.45 m diameter, and 0.025 m thick was assessed in June 2018. The variation in solar beam radiation over the entire day was observed from 840 W/m2 to 1278 W/m2, while, the absorber plate temperature was recorded within the extent of 116–195°C, however, the maximum heating temperature was measured 129°C at the end-use. The Scheffler collectors performed appropriately in the morning and evening time with substantial heat loss factor and lower optical efficiency factor. The energy efficiency of 59.28% has been achieved which is higher as compared to the parabolic solar concentrator. The higher concentration ratio of the Scheffler collector indicates it as an efficient substitute to replace fossil fuels. The system is viable for more than 1600 kWh/m2 yearly solar potential while the cost of heating is greater than 0.05 $/kWh for them. This paper concludes that the Scheffler reflector is the most promising solar technology for the medium-temperature applications.

Keywords

• Energy efficiency
• Performance evaluation
• Scheffler collector
• Solar
• Thermal applications

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