V. DESIGN CONSIDERATIONS
Smaller PV systems should be thought of as energy sources, and the objective is to convert as much of the available insolation as possible into useable electrical energy. However, practical loads have both energy and power requirements. As such, a critical analysis of the loads is necessary before designing PV systems for specific applications. Often, an associated energy storage and reconversion system enables the designer to meet the power requirements in the case of stand-alone systems. With utility interconnection, the problem is considerably simplified. The standard test conditions for rating PV modules is 25˚C, 1 kW/m2, and a wind speed of less than 1 m/s. Normal operating conditions are closer to 40˚C, 850 W/m2 and wind speed of < 1 m8/s for calm sites. These differences point to a need for modified rating to be used in designing PV systems.