How the calculator works
Transparent assumptions, plain-English math
The calculator multiplies your panel count by 420 watts, converts that to kilowatts, then estimates yearly production exposure using 365 days and 5 peak sun hours per day. The selected cleaning interval applies a soiling-loss percentage, and your ZIP code estimates the electricity rate used to value that lost production.
- Never cleaned: 20% estimated loss.
- 6 months: 10% estimated loss.
- 1 year: 15% estimated loss.
- 2 years: 18% estimated loss.
- 3+ years: 25% estimated loss.
Safe cleaning matters. Cable Pressure Washing and Solar Panel Cleaning uses deionized water, water-fed poles, low pressure, and no walking on your modules. See our solar panel cleaning guide and solar cleaning statistics for more context.