Resources
Solar cleaning, demystified.
Plain-English answers to the questions Wisconsin solar owners actually ask. Written by Marquis Mason, owner of Solar Alchemist.
Guides
June 28, 2026 · 5 min read
Why Rain Doesn't Clean Your Solar Panels in Wisconsin
Wisconsin rainfall is rich in dissolved minerals and concentrates particulate matter on panel edges. Here's exactly why "the rain will clean it" is the most expensive myth in residential solar.
Read articleJune 28, 2026 · 4 min read
What the Wisconsin State Capitol Job Taught Us About Solar Panel Soiling
A 16-year-old rooftop array. One warranty-safe cleaning. +16.7% production lift the same day. Here are the before/after numbers and what they mean for any commercial array in Southern WI.
Read articleJune 28, 2026 · 5 min read
Solar Panel Cleaning and Your Warranty: What You Need to Know
Most warranty-voiding cleaning mistakes are silent. This guide walks through what every major panel manufacturer requires and exactly which cleaning techniques preserve your coverage.
Read articleSources & Citations
Every factual claim on the site is anchored to a public source. Grouped below by topic so procurement, insurance, and homeowner audits can verify quickly.
Production Loss & Soiling Research
Why we claim 5–15% annual loss for typical U.S. systems, higher in pollen and agricultural zones.
- NREL — Soiling Losses Quantitative Study (2024) — National Renewable Energy Laboratory. Annual soiling losses across U.S. PV fleets — median ~5%, with regional variation up to 15%+.
- NREL — Addressing Soiling on PV Modules — NREL Research Hub. Field methodology and cleaning-recovery measurements across multiple climates.
- IEA-PVPS — Soiling Losses Impact on PV Performance — International Energy Agency, PV Power Systems Programme. Agricultural soiling rates regularly exceeding 15% annually without intervention.
- Princeton — Regular Panel Cleaning & Air Quality (2021) — Princeton Environment in the Half Century. Regular cleaning + air-quality improvements raise PV output, especially in high-pollution / low-rain regions.
Rain Cannot Clean Pollen
Why we tell visitors that rain alone is not enough — backed by NREL field research.
- NREL — Rain Not Enough to Wash Pollen from Solar Panels (2023) — NREL News Program. Direct NREL release stating rain alone is insufficient to remove pollen, requiring scheduled cleaning.
- Renewable Energy World — NREL Pollen Study Summary — Renewable Energy World. Independent reporting on the 2023 NREL pollen findings: >15% peak losses during pollen season.
Wisconsin State Capitol Solar Array
Verification of our most-cited customer outcome — the 2009 installation we cleaned in 2025.
- Renew Wisconsin — Solar Panels Rise to Capitol Heights — Renew Wisconsin. Confirms install date (2009), 48-panel count, ~9,600 sq ft installation, MGE-owned. The +16.7% production lift after our cleaning is our own measured data — see /our-work for the irradiance readings.
Insurance, Warranty & Wear-and-Tear
Why a paper trail of professional cleanings protects your homeowner / commercial policy and warranty.
- Insurance Information Institute — HO-3 Sample Policy (PDF) — III.org. Standard HO-3 form explicitly excludes wear-and-tear, deterioration, and neglect — insurers use this exact policy language.
- NAIC — Homeowners Insurance Topics — National Association of Insurance Commissioners. Industry-level confirmation of policy-form prevalence and exclusions.
Cleaning Method, Brushes & Deionized Water
Why we use soft rotary brushes + deionized water — backed by manufacturer documentation.
- LG Solar — Official Cleaning Guidance — LG.com. LG officially recommends deionized water + non-abrasive brush; advises against tap water, abrasives, and cleaning agents.
- Enphase — Solar Panel Cleaning Guide — Enphase Energy. Industry-standard soft-brush / gentle-rinse protocol.
Local Wisconsin & Electric-Rate Data
Why we use $0.16/kWh and warn about hard-water mineral deposits in the Madison area.
- U.S. EIA — Wisconsin Residential Electricity Profile — U.S. Energy Information Administration. Wisconsin residential average ~$0.16/kWh (used in our $80–$250/yr soiling-loss math).
- Madison Metropolitan Sewerage District — Water Hardness — madsewer.org. Confirms hard water in the Madison area — the mineral source for the white spotting we remove with deionized rinse.
- NREL — PV Degradation Rates Review (1,900-system meta-study) — NREL. Median panel degradation of ~0.5%/year (used to distinguish slow degradation from sudden soiling losses).