PR-Drift Calculator — 25-Year Estimate

How much revenue is your solar plant losing to PR drift?

A C&I rooftop solar plant running at 78–81% Performance Ratio — versus the 82–86% benchmark — bleeds roughly ₹2.6–3.2 lakhs/year to unmanaged soiling. Punch in your plant size, tariff, and observed PR drift below, and we'll show the monthly + cumulative 25-year revenue loss in seconds.


Your plant inputs
DC array capacity at peak sun
kWp
DISCOM C&I rate you pay
₹/kWh
% below the 82–86% benchmark you suspect on your plant
%
Quick presets:

How the numbers are computed

The headline loss figure comes from three inputs you control: plant size (kWp), tariff (₹/kWh) and observed PR drift (%). We anchor to a 1,500 kWh/kWp/yr specific-yield baseline (the figure cited in our warehouse case study and validated against Open-Meteo irradiance data across our monitored rooftops) and a 82–86% Performance Ratio benchmark.

The kWh deficit per month is the gap between expected and observed generation at your PR drift. The rupee loss is that deficit multiplied by your DISCOM tariff. Multiplying out across a 25-year asset life — without escalation — gives the cumulative figure.

The cleaning-alert equivalent converts the rupee loss into "cleaning events worth running this year" — at roughly ₹8,000–12,000 per cleaning event on a 250 kWp plant, the cleaning ROI on a 7% PR-drift plant is typically 2.5–4x. Want the per-plant figure, not a national average? The warehouse case study walks the full logic.

See What BijleeAI Catches on Your Plant

Run a free pilot — drop a CSV from any plant you operate. The 24-hour audit emails the PR-drift, soiling and string-anomaly findings.

Start the Free Pilot → Book a Free Audit