Knowledge
Reading your electricity bill to size kWp
Use the kWh and amount on your bill to estimate a suitable solar capacity for your business.
Your bill gives two key numbers: Energy used (kWh) and the total amount. Divide the amount by kWh to get the average tariff you pay.
Average several months
Consumption varies with season and orders. Take at least 3 months, ideally 12, and average them.
Estimate the daytime share
If the bill splits normal, peak and off-peak hours, you can see daytime use. If not, estimate from your shifts. A single-shift factory usually uses most of its power in daytime.
From kWh to kWp
In Ninh Binh, each kWp of panels on a 10° south-facing roof produces about 1,166 kWh per year, or about 97 kWh per month (PVGIS, including 14% system losses). Example: 21,000 kWh of daytime use per month needs about 21,000 / 97 ≈ 216 kWp, before days off and degradation.
The web calculator does this month by month, including days off and roof area.
Updated 2026-10-28