Construction and Engineering
Solar Panel Calculator
Solar Panel Calculator size a simplified solar array from daily energy use, peak sun hours, system efficiency, and panel rating.
Construction and Engineering
Solar Panel Calculator
Size a simplified solar array from daily energy use, peak sun hours, system efficiency, and panel rating.
Formula
Required array kW = daily kWh/(peak sun hours*system efficiency); panels = ceil(required watts/panel watts).
About the Solar Panel Calculator
Size a simplified solar array from daily energy use, peak sun hours, system efficiency, and panel rating.
How the Solar Panel Calculator Works
Daily energy is divided by effective sun hours to obtain required nameplate power, then whole panel count and installed capacity are reported.
Formula
Required array kW = daily kWh/(peak sun hours*system efficiency); panels = ceil(required watts/panel watts).
The calculation runs in your browser. Values are validated for required ranges, compatible units, and method-specific restrictions before results are displayed.
Required Inputs
- Daily energy use (required) - enter in kWh/day.
- Peak sun hours (required) - enter in hours/day.
- Overall system efficiency (required) - enter in %.
- Panel rating (required) - enter in W.
Results Reported
The result panel reports the final answer and the intermediate quantities needed to check the calculation:
- Required array capacity (kW)
- Panels required
- Installed panel capacity (kW)
- Estimated daily generation (kWh/day)
- Estimated annual generation (kWh/year)
Solar Panel Calculator Example
Select Example Data in the calculator to load this reproducible input set:
| Input | Example value |
|---|---|
| Daily energy use | 30 kWh/day |
| Peak sun hours | 5 hours/day |
| Overall system efficiency | 80 % |
| Panel rating | 400 W |
How to Use the Calculator
- Confirm that the calculator title and formula match the quantity you need.
- Enter every required value using the unit shown with its field.
- Select Example Data to inspect a valid input set, or enter your own values and select Calculate.
- Review all reported values and the displayed formula before using the answer.
- Use Copy Result or Download CSV when you need a reusable record.
Accuracy and Limitations
Shading, orientation, temperature, clipping, degradation, batteries, tariffs, weather variation, structure, and electrical rules require a site-specific design.
Keep units consistent, use measurements that represent the actual situation, retain full precision during the calculation, and round only the final answer. Professional decisions may require current official rules, field measurements, laboratory methods, or specialist review.
Frequently Asked Questions
What does the Solar Panel Calculator calculate?
Size a simplified solar array from daily energy use, peak sun hours, system efficiency, and panel rating.
Which formula does the Solar Panel Calculator use?
Required array kW = daily kWh/(peak sun hours*system efficiency); panels = ceil(required watts/panel watts).
What should I verify before using this result?
Shading, orientation, temperature, clipping, degradation, batteries, tariffs, weather variation, structure, and electrical rules require a site-specific design.