Because the stc rating is a measurement calculated under ideal laboratory conditions it s not always a useful metric for designing your system.
Pv solar panels ptc ratings.
What are solar panel ptc ratings.
The jinko solar jkm260p 60 watts polycrystalline module has a ptc rating of 238 2 watts and an stc rating of 260 watts.
Meaning the normal expected pv condition expected on a utility scale project.
Ptc power rating power ratings measure a solar panel s power output in watts.
The pv panels in my system are made by the rec group the model is rec215ae us.
The ptc of solar panels with stc rating of 260 watts varies in the gosolarcalifornia table.
Stc ratings are always higher than ptc because they are based on the modules instant output under ideal conditions.
Ambient temperature at 10 meters above ground level and wind speed of 1 meter.
So what is ptc rating on a solar module and how is it used.
The percentage drop off depends largely on the type of solar panel materials used and the manufacturer.
The ptc rating represents a more real life condition of 1 000 watts per square meter solar irradiance 1 5 air mass and 20 degrees c.
Every panel is assigned a nameplate power output value which is measured using stc standard test conditions.
Their ptc ratings varied from 217 1 watts ptc stc 0 835 to 239 8 watts ptc stc 0 922 the canadian solar panel referenced above is at the high end of the scale ptc stc 0 919 it s important to note what the ptc testing reveals not all panels with the same stc rating perform the same.
In the 1990s the national renewable energy laboratory nrel developed a set of pv test.
For the sake of example if you are getting 5 hours of direct sunlight per day in a sunny state like california you can calculate your solar panel output this way.
Ptc is an acronym for pv usa test conditions which were developed at the pv usa test site at the university of davis california.
Ptc is often referred to as pvusa test condition but more explicitly it is photovoltaics for utility scale applications test condition.
Each pv panel is rated at 215 watts under stc conditions and 187 watts under ptc conditions.
Stc stands for standard test conditions.
Thus the output for each solar panel in your array would.
Pv panels nominal ratings and real production.
Stc standard test condtions and ptc pvusa test conditions are the two methods of testing module performance.
The stc and ptc ratings of solar panels are one of the ways of comparing the performance of one brand and or type of solar panel to another.
If you want to know how photovoltaic panels will perform in the real world look for their ptc ratings.
5 hours x 290 watts an example wattage of a premium solar panel 1 450 watts hours or roughly 1 5 kilowatt hours kwh.