Economic feasibility of grid-connected photovoltaic systems

Photovoltaic systems convert sunlight into direct electrical current. There are two types of photovoltaic systems for building applications. These types are stand-alone and grid-connected systems. As their names imply, these systems are distinguished by their interaction with the electric utility. Since stand-alone systems are not connected with the utility, any electricity that cannot be used by on-site loads must be stored or dissipated. With the grid-connected systems, this excess electricity can be fed back to the grid. This paper also presents the simulation studies on the performance of a 5 kW grid connected system for various locations in Malaysia. Six locations namely, Kuching, Kota Kinabalu, Kota Bharu, Senai, Bayan Lepas, and Kuala Lumpur are selected for this study. Long term performance parameters such as monthly photovoltaic cell efficiency and conversion of DC to A C have been predicted using the local meteorological data and system design parameters. An economic feasibility studies on the performance of this system have been conducted in UKM Bangi. The payback period of this system is calculated in relation with the changes of price per kWh paid by the utility and also the variation of the initial investment.