Pv Solar Panels Ptc Ratings

They are very important when more than one solar panel is to be used together in an array.

Pv solar panels ptc ratings.

Stc stands for standard test conditions. 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. The pv panels in my system are made by the rec group the model is rec215ae us.

In the 1990s the national renewable energy laboratory nrel developed a set of pv test. 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. Meaning the normal expected pv condition expected on a utility scale project.

So what is ptc rating on a solar module and how is it used. Every panel is assigned a nameplate power output value which is measured using stc standard test conditions. Because the stc rating is a measurement calculated under ideal laboratory conditions it s not always a useful metric for designing your system. How much energy does a solar panel produce.

Ambient temperature at 10 meters above ground level and wind speed of 1 meter. 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. Pv panels nominal ratings and real production. Stc standard test condtions and ptc pvusa test conditions are the two methods of testing module performance.

5 hours x 290 watts an example wattage of a premium solar panel 1 450 watts hours or roughly 1 5 kilowatt hours kwh. As the panel heats up as they all do in the real world its output goes down. Ptc power rating power ratings measure a solar panel s power output in watts. If you want to know how photovoltaic panels will perform in the real world look for their ptc ratings.

Thus the output for each solar panel in your array would. The jinko solar jkm260p 60 watts polycrystalline module has a ptc rating of 238 2 watts and an stc rating of 260 watts. Each pv panel is rated at 215 watts under stc conditions and 187 watts under ptc 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.

The percentage drop off depends largely on the type of solar panel materials used and the manufacturer.