What is the PTC rating on a Solar Panel and why is it important?
When receiving a quote for solar power, it’s best to make sure the solar panels quoted output are using the PTC benchmark. But what does that mean?
STC (Standard Test Conditions) – the solar panel’s output is tested in a lab, the output stated by the manufacturer
PTC (PVUSA Test Conditions) – the solar panel’s output it tested in real world conditions at the PVUSA testing center in Davis, California. The PTC rating is typically 10-15% lower than the STC rating.
The real neat part of the PVUSA testing center is the setup. PVUSA lines up solar panels from different manufacturers and puts them head to head and records the output data, an independent test of output, which is great number for consumers to look at when shopping for solar panels. Below are some satellite images of the PVUSA testing center.
The PVUSA testing center is a 800kW facility with all the latest solar panels: