Unique Aspects of Terrestrial Photovoltaic System Design

The design of terrestrial photovoltaic power systems involves a process of optimization of elements quite different from that employed in conventional power sources. Solar input varies locally and temporally. Efficiency of conversion to electricity is highly dependent upon collector concentration ratio, orientation and tracking capability, and optical and solar cell technologies employed; other variations occur with temperature and changes in reflective and transmissive properties of components. Reliability is dependent upon system complexity and hardware selected. Energy storage needs are a dual function of the fluctuating solar input and load profile, with a substantial range of photovoltaic array size/storage tradeoffs available in designing a stand-alone system. Key aspects to be considered in the design of a photovoltaic power system are discussed in this paper, with a specific application treated in detail as an example of their implementation.