Solar Panel Sizing Calculator
Calculate how many solar panels you need to cover your electricity usage based on consumption and location.
How It Works
Enter your monthly electricity usage, panel wattage, peak sun hours, and system efficiency. The calculator tells you exactly how many panels to install to meet your energy needs.
Formula
Panels Needed = Monthly kWh / (Panel Watts x Sun Hours x 30 / 1000 x Efficiency)
Frequently Asked Questions
Should I oversize my solar system?
Sizing for 100-110% of current usage is common. If you plan to add an EV or heat pump, size for future load. Net metering allows you to bank excess generation.
What affects how many panels I need?
Monthly kWh usage (from your bill), panel wattage (higher W = fewer panels), peak sun hours (location-dependent), and system losses from shading, inverter efficiency, and temperature.