What Soils Arrays in This Region
Tree and grass pollen is heavy from late March through May across the whole tri-state, producing a uniform film that dulls the entire array at once. Bird droppings and nesting are the highest-impact soiling per square inch — on string inverter systems shading part of one cell can drag performance across a string disproportionately. Agricultural dust is relevant to ground-mount arrays near working farmland in Salem, Gloucester, Cumberland and Chester counties. Industrial and traffic particulate accumulates faster on sites along I-95, Route 130, the Wilmington corridor and near heavy industry. Rain does not clean an array — rain removes loose material and dries leaving mineral film.
Justifying the Spend with Your Own Data
Your monitoring platform is a better argument than any industry average. Compare current production against the same weeks in prior years. Look for divergence between strings or inverters — uniform decline points to general soiling, one string underperforming points to a localized obstruction. Check whether the last significant rain improved anything — if it did not, the soiling is bonded rather than loose. That four-line analysis converts a maintenance request into a return calculation.
How Commercial Arrays Are Cleaned Properly
Deionized water, no detergent: purified water lifts soiling and dries without residue. Soft brush or water-fed pole: the anti-reflective coating on the glass is thin and it is the thing being protected. No pressure washing: force can breach the frame seal and drive water toward the junction box or under the laminate. No one walks on modules: standing on panels causes microcracks that do not show visually and do show in production data later. Documentation: before and after production figures, panel condition notes, and photographs of anything found.
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