Performance evaluation of a stand-alone solar dish Stirling system for off–grid electrification

ABSTRACT

The performance of solar-powered Stirling engine system with a parabolic dish collector to electrify rural residential houses is presented. The developed model considers both the nonlinearized heat losses of the solar dish collector and the effect of the irreversibility of the Stirling engine. Governing equations for the solar collector, receiver heat transfer, thermodynamic cycle for Stirling engine, and mechanical and electric energy conversion are integrated and simulated in MATLAB software. Validation of the current model against experimental data is found in a very good match. A simulated model located in southern Jordan is built as a case study. The model simulates the hourly thermal to the electric conversion of solar energy to meet the required household load. The simulations results predict that overall system efficiency during summer is around 30% while it is around 22% during wintertime. The optimal concentration ratio is about 230 for the current solar dish Stirling engines configuration studied in this work. Furthermore, the load of loss probability is found to decrease linearly with increasing collector size. It was found that the solar dish Stirling engine with proper reflector size can meet the load demand with high reliability factor. Finally, storage capacity equal to daily energy demand is sufficient to meet uncontrollable load under varying weather conditions during summer, spring, and fall seasons in Jordan.

KEYWORDS:

• Stirling engines
• thermal losses
• energy conversion
• conversion efficiency
• numerical simulations

Disclosure statement

No potential conflict of interest was reported by the author(s).

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