Warshauer Electric Supply

Always be sure when you are selecting your solar system that you are sure to compare the real world outputs of the solar module. Below is a brief explanation of the nuts and bolts of the testing standards used for solar systems. It can be best compared to the Miles Per Gallon rating for your vehicle, there is always a difference between what the vehicle is rated for and how it actually performs in the real world. PTC is an attempt to simulate the conditions that the system will encounter in the real world. Always be sure that when comparing solar modules you are comparing PTC to PTC. It's the best way to ensure that you selecting the most efficient module for your application.

Difference Between PTC and STC

• 1000 W/sq. meter
• 1.5 air mass
• 25 deg. C

• 1000 W/sq. meter
• 1.5 Air mass
• 20 Deg. C
• 10 meters above ground level
• Wind speed of 1 m/s

STC are testing parameters built around ideal conditions and optimal performance. PTC ratings allow a more accurate perception of the real world performance of a solar module. Taking the PTC rating of a panel into account with the design allows for more accurate performance expectations and ROI analysis. The true performance of a panel is more readily ascertained with the PTC value.