Fouling of PV panels can be induced by the presence of dust, air pollution, sand, salt, bird droppings, snow, etc. The impact on production is usually assessed during the initial energy yield evaluation (ERE).
The impact on production is usually assessed during the initial energy yield evaluation (ERE). The impact on production is usually assessed during the initial energy yield evaluation (EYA). It is generally assumed that losses due to soiling are estimated to be at least 1% per year (linear) for a typical installation design (panel tilt angle between 15° and 25°) and a “standard” location (country or city). For a specific location, it is strongly recommended to assess potential losses more precisely in terms of seasonality (non-linear losses), location and environmental specificities (sandstorms in deserts, bird droppings near the sea…).
Losses are greater if the angle of inclination of the panels is low (less than 10°). This impact on losses must also be monitored during operation:
(i) to ensure system performance
(ii) to adjust fouling loss values
(iii) to assess whether module cleaning is necessary.
This will make it possible to adjust the OPEX in the business plan by adding or deleting module cleaning interventions.
By David Roisse, Asset Manager