Soiling Forecast and Measurements for large PV Power Generation Projects in Dessert Environments.

Levels of atmospheric dust in dessert geographical regions are amongst the highest across diverse climatological systems. In these types of climates atmospheric dust content strongly depends on the target location and often presents specific seasonal patterns. The performance of photovoltaic power plants operating in such dessert conditions will deteriorate by the accumulation of dust particles upon the glass front plate of PV Modules (Soiling). Successful Engineering, Finance, Operation & Maintenance of utility scale power plants therefore require a sound estimation of a one-year, time-dependent soiling profile for each particular project site. This can be achieved, time allowed, during the course of preliminary on-site studies based on outdoor measurements. In other circumstances soiling estimations will be required. This work is focused on the determination of soiling loss profiles using qualified outdoor measurements from a reference site extended with the application of time series of satellite based solar irradiation and aerosol optical depth data and a combination of four-months ground measurements of comparative (clean/soiled) module performance for a site located in a region of the Nubian Dessert (Egypt).