PV Availability Testing, Built for Handover

An availability test demonstrates that a plant's equipment — typically its inverters — was operational during the hours it should have been producing. Time only counts when conditions are eligible: irradiance above an agreed threshold and the plant exporting. Many EPC contracts require an availability test at substantial completion, commonly with a guaranteed availability of 98–99% or higher over a set number of consecutive days. Availability guarantees also appear in O&M contracts.

No. IEC TS 63019 provides an information model and IEC TS 61724-3 an energy-based evaluation framework, but neither prescribes a single formula — and real contracts define availability in materially different ways, with different thresholds, exclusions, and measurement boundaries. That is why HelioTest treats your contract's definitions as explicit, configurable settings instead of claiming a one-size-fits-all standard.

Inverter AC power, plane-of-array irradiance, and meter export power as timeseries CSV exports — plus inverter status codes if your data source provides them (recommended, since status codes give the most accurate classification). No PVsyst model or energy simulation is needed.

Through a documented event log. Grid outages remove intervals from the test and extend the window to compensate. Excused events waive charging for downtime that is not the contractor's responsibility. Data corrections require a written justification. Every event's effect is quantified in the report, and downtime with no documented cause is flagged rather than hidden.

Missing data during eligible time counts against availability unless a documented correction explains it — the conservative reading, so gaps can never silently improve the result. Quality checks flag how much of the result rests on missing data, and if the data does not cover the whole test window the run is marked provisional instead of passed.

Yes. The managed service runs availability tests as an add-on to a capacity test engagement or standalone — you receive the full deliverable package and keep live access to the project. Learn more about the managed testing service.