Why do we need a performance guarantee for a large photovoltaic system?

Documentation of the energy yield of a large photovoltaic (PV) system over a substantial period can be useful to measure a performance guarantee, as an assessment of the health of the system, for verification of a performance model to then be applied to a new system, or for a variety of other purposes.

How can a PV performance model be used?

The most straightforward approach is to use the same PV performance model as used for the original performance prediction, but revised for as-built clean and new condition and using the actual weather measured during the energy test converted to the input format (such as TMY) required for the PV performance model (e.g. SAM or PVSyst).

Do PV system commissioning standards require performance testing?

This best practice guide is PV System Commissioning or re-Commissioning Guide Supplement to characterize and maximize PV system performance. If a PV system is commissioned using industry standards, then it should produce as much energy as was expected, right? No, PV industry commissioning standards do not call for performance testing.

How do you document a photovoltaic system?

Example Table Documenting the Meteorological Input Parameters to the The power generation of a photovoltaic (PV) system may be documented by a capacity test [1, 2] that quantifies the power output of the system at set conditions, such as an irradiance of 1000 W/m2, an ambient temperature of 20°C, and a wind speed of 1 m/s.

How to evaluate PV system capacity?

A simple method to evaluate the PV system capacity is to determine the nominal DC rating of the system at STC, measure POA irradiance, calculate cell temperature based on module back-side or ambient temperature using Sandia model, and estimate/calculate/determine values for the derate factors familiar to the industry.

How do you test a photovoltaic system?

The power generation of a photovoltaic (PV) system may be documented by a capacity test [1, 2] that quantifies the power output of the system at set conditions, such as an irradiance of 1000 W/m2, an ambient temperature of 20°C, and a wind speed of 1 m/s. A longer test must be used to verify the system performance under a range of conditions.