Feasibility evaluation of stand-alone photovoltaic systems for residential loads

Solar energy offers enormous potential to be used as an alternative energy source due to its advantageous features and environment friendliness, using photovoltaic equipment. This study examines the feasibility of a stand-alone photovoltaic system to meet the electrical energy demand of a residential house in the vicinity of Faisalabad, Pakistan. A complete design methodology has been presented along with its economic analysis in terms of life cycle cost (LCC). Sizing of each component of the PV system has been done using this model as per the load requirement and average solar irradiance falling in that region. The calculated unit cost of electrical energy produced by solar based stand-alone PV system is found to be PKR 13.5 (KWh)⁻¹ which indicates the cost-effectiveness of this technology as compared to conventional electricity supplied by utility grid. So, it is concluded that electricity produced by a stand-alone (off-grid) PV system is both technically and economically viable and an attractive alternative as compared to centralized grid supply for residential use.