Translations:Design process overview/3/en

The approach to design is exceedingly important though as it is the first step in building a PV system that will perform properly and that will withstand the test of time. An improperly designed system, regardless of how well it is installed or the quality of the components that are used, will not perform as it should. The starting point for any design is an analysis of the loads that the system will be required to power and for how long, an analysis of the solar resource throughout the year, the parameters chosen for the efficiency of various system components, and the chosen design specifications for the system. Conservative values should be used for each of these variables. Playing with these numbers or using numbers that are not conservative can lead to a smaller and lower-cost design, but that will not meet end user needs and will not last as it should. Determining appropriate values for to use for calculations involving the solar resource or weather can be challenging for many locations as there may not be locally gathered data that can be relied upon. There are tools that use globally calculated data and perform calculations to estimate the solar resource and annual weather for locations throughout the world, but there is no one perfect tool. The general design principle underlying off-grid PV system is to design for the worst-case scenario in terms of poor solar resource and load usage. Yearly and monthly averages can sometimes hide periods of poor weather and limited solar resource; therefore, it can be useful to consult various resources that have daily/weekly data and have discussions with people from the region.