Enphase Energy Inc.
01/06/2025 | Press release | Distributed by Public on 01/07/2025 02:38
Solar panel size and weight: everything you need to know
How to calculate solar panel dimensions for your system
To determine whether a PV installation will fit on your roof or property, you can calculate your total solar panel dimensions based on the energy-generating capacity of your system. Permitted that there is enough installation space available on your property, most home solar panel systems are designed with a capacity expected to produce approximately the same amount of electricity consumed on-site annually.
While most home PV systems have a rated capacity between 3 kW and 15 kW, the majority of residential installations will fall somewhere been 6 kW and 11 kW. After you calculate your PV capacity, you can then find the number of solar panels and total area you will need for your installation.
Today, most home solar panels are rated between 300 watts and 450 watts. To fully illustrate how solar panel dimensions vary by installation, the chart below shows the estimated square footage of small, average, and large home PV systems with two different panel wattages considered.
| Total system capacity | Panel wattage | Number of panels | Space required (17.6 sq ft per panel) |
|---|---|---|---|
| 4 kW (small) | 350W | 11 | 194 sq ft |
| 4 kW | 400W | 10 | 176 sq ft |
| 4 kW | 450W | 9 | 158 sq ft |
| 7 kW (average) | 350W | 20 | 352 sq ft |
| 7 kW | 400W | 18 | 317 sq ft |
| 7 kW | 450W | 16 | 282 sq ft |
| 11 kW (large) | 350W | 31 | 546 sq ft |
| 11 kW | 400W | 28 | 493 sq ft |
| 11 kW | 450W | 25 | 440 sq ft |
In addition to solar panel square footage, several other installation factors must be evaluated when determining where your PV system can be installed. For safe and legal operation, solar panels must be properly spaced, both horizontally and row-to-row, and installed up to local building codes, at proper lengths away from ridges, edges, chimneys, dormers, vents, and other roof obstructions.
To maximize your home's solar power potential, we recommend designing a system with high-efficiency panels and microinverters, as well as finding a solar installer that is familiar with local building regulations and solar policies in your area.