System availability chart | mc Help Center

Last modified: 2025-08-20

Chart

View the chart at System level under Evaluation.

Basic info

Description	System availability is the percentage of a system that is available over a period of time. It is an indicator of how quickly faults are identified and remedied.
Prerequisites	Energy sum at system level : Defined as the term E_Z_EVU Plane of array irradiance (POAI) data from a sensor: Defined as the term G_M0 or satellite data. Default threshold value is greater than 100W/m²
Further details	Standard formula and calculation The following system availability formula is used by default: Default system availability formula Within the measurement interval, the entire plant is either available (100%) or not available (0%). If the energy is not equal to 0 within an interval, the availability is 100%. System availability is only calculated during intervals where POA irradiance is greater than 100 W/m². Intervals in which energy data is missing are treated as if the system is available. Only data for completed days is displayed. Note The standard formula is displayed for basic partners. The VCOM module KPI editor for PR and system availabilityallows you to adapt the input parameters to your needs.

Description

System availability is the percentage of a system that is available over a period of time. It is an indicator of how quickly faults are identified and remedied.

Prerequisites

Energy sum at system level : Defined as the term E_Z_EVU
Plane of array irradiance (POAI) data from a sensor: Defined as the term G_M0 or satellite data.
Default threshold value is greater than 100W/m²

Further details

Standard formula and calculation

The following system availability formula is used by default:

Within the measurement interval, the entire plant is either available (100%) or not available (0%). If the energy is not equal to 0 within an interval, the availability is 100%.
System availability is only calculated during intervals where POA irradiance is greater than 100 W/m².
Intervals in which energy data is missing are treated as if the system is available.
Only data for completed days is displayed.

Note

The standard formula is displayed for basic partners. The VCOM module KPI editor for PR and system availabilityallows you to adapt the input parameters to your needs.

Note

Find further information on the general functions within charts under Evaluations & charts.

Sample calculation

The following sample calculation is based on the standard PR formula:

Interval	POA irradiance (W/m²)	Energy (kWh)	Result
I1	90	10	Not rated
I2	125	20	100%
I3	200	30	100%
I4	80	0	Not rated
I5	250	0	0%
I6	200	NULL*	100%
I7	150	30	100%
I8	130	20	100%
I9	110	0	0%
System availability			5/(5+2) = 71.4%
*NULL means no data available for this interval.