Techno-economic optimization of hybrid solar system with energy storage for increasing the energy independence in green buildings

Abstract

The optimal design and optimization of the hybrid renewable energy system powered by photovoltaic panels (PV) with appropriate backup energy storage is the essential for increasing the energy independence in green buildings. This paper designs and compares hybrid PV panel with two main energy storage systems in remote areas (PV/battery and the off-grid PV/hydrogen system). These hybrid renewable energy systems are capable for producing steady output to the grid at the least total annual cost (TAC) of system, with maximum acceptable lack of power supply probability. A particle swarm optimization (PSO) has been developed using MATLAB to optimally design a hybrid PV/battery/hydrogen system. To confirm the superiority of the PSO method, the optimization problem was implemented in 1 to 30 independent executions and the best result was reported. Actual meteorological data in China is selected to test the concept of the off-grid solar energy system. The effect of changes in system reliability, number of run, and interest rate on the design results of two systems are compared and analyzed. The research found that the PV/battery system in remote areas becomes more economical than the off-grid PV/hydrogen system as reliability decreases and interest rate increases. Also, the total configured capacity of solar panel in the PV/battery structure is smaller (by 44.8 %) than that of the PV/hydrogen structure. Moreover, with the increase of number of run from 1 to 20, the number of components, in the PV/hydrogen system is adjusted to decrease the TAC (by 2.2 %), and the TAC of the PV/battery also decreases by 0.23 %.