Solar Performance Ratio Calculator

How Solar Performance Ratio works

The calculation starts with PR = delivered ÷ reference × 100. Solar Performance Ratio uses Delivered energy, Reference energy to report Performance ratio.

With the loaded values, performance ratio evaluates to 80.00%. Preserve the baseline before changing a value.

Inputs for Solar Performance Ratio

Delivered energy and Reference energy belong to Solar Performance Ratio. Keep source units with delivered energy.

The preset case is instructional rather than prescriptive. Enter the applicable electrical data. Use Solar Payback Calculator as the follow-up for simple payback.

Delivered energy

Example entry: 7200 kWh.

Reference energy

Example entry: 9000 kWh.

Reading the Solar Performance Ratio result

This output represents Solar Performance Ratio. For azimuth-adjusted energy, use Solar Azimuth Loss Calculator.

Finish the selection with standard sizes, operating limits, and transient review.

Measurement and units

Use site-specific irradiance, temperature, shading, equipment limits, and measured system losses. Check prefixes on delivered energy.

Use the same unit basis and observation location in alternate cases.

Limits of this calculation

Define reference energy consistently across comparisons.

A complete system can contain effects that this equation does not represent. Unentered effects remain outside Solar Performance Ratio. Compare this result with Solar String Voltage Calculator when string voltage is also needed.

A useful Solar Performance Ratio comparison

Record performance ratio before testing a different delivered energy value. If the next question concerns required storage, open Off-Grid Battery Bank Calculator.

Document the alternate delivered energy source.

Questions about Solar Performance Ratio