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Greenbyte Documentation

Grid Meter/Production Meter Performance Ratio Time Window

The Performance Ratio Time Window for Production meters and Grid meters is an aggregated metric of the solar PV system, limited to a selected time window within a day. It compares the meter’s actual energy to the sum of all inverters’ (connected to that meter) potential energy for when irradiance is above cut-in, for this time window. The Performance Ratio can be used to find sites/sub-sites/inverters that under-perform during normal operation.

Remarks

Required metadata fields:

  • Performance Irradiance Cut-In (W/m2) (Inverter metadata 13), for reference inverters/inverters in site

  • Performance Irradiance Cut-In (W/m2) (Device metadata 16), for meter

  • Performance Time Window Start (hh) (Device metadata 17)

  • Performance Time Window End (hh) (Device metadata 18)

Technology

Solar

Equation
Grid_Meter-Production_Meter_Performance_Ratio_Time_Window_-_Equation.png

Where:

PR

is the Grid Meter Performance Ratio Time Window/Production Meter Performance Ratio Time Window

Egrid

is the Energy Export Meter, used for a Grid meter

EGMS

is the Energy Export GMS Meter, used for a Performance meter

I

is the average Solar Irradiance Reference Meter for Inverters

Cut-inIP

is the Performance Irradiance Cut-In (W/m2) (Device metadata 16) for meter

Pp,i

is the Cascading Potential Power - Solar for inverter i

Cut-inIP,i

is the Performance Irradiance Cut-In (W/m2) (Inverter metadata 13) for inverter i

T

is device resolution in hours

TTWstart

is Performance Time Window Start (hh), a defined starting hour, T >= TTWstart. (Device metadata 17)

TTWend

is Performance Time Window End (hh), a defined ending hour, T < TTWend. (Device metadata 18)

Epotential

assumes 10-minute data.

Note

For other device resolutions, the denominator will be different.

Inputs
Grid_Meter-Production_Meter_Performance_Ratio_Time_Window_-_Inputs.png
Usage Example
Grid_Meter-Production_Meter_Performance_Ratio_Time_Window_-_Usage_Example.png