Solar photovoltaic systems convert solar energy directly into electrical energy and the power obtained from this conversion is DC. This paper deals with the constructional details and condition monitoring of a stand alon e, grid interconnected solar photo voltaic roof top (PVRT) generation system, monitoring the inverter current fed to the plant utilities. The constructional hazards of the system have been considered and new t echnique ha s been presented for effective condi tion monitoring in the system. Also effective cost and payback period optimization in the power plants have been carried out with and without solar PVRT systems.