Solar Panel Ptc Test Conditions

Under ptc lighting conditions are the same as the stc but the solar module is heated to a more realistic operating temperature of 113 degrees.

Solar panel ptc test conditions.

As compared to stc ptc is an approach to closer meet real world conditions and measure the actual performance of the modules. The ptc measures panel output under more realistic conditions. As compared to standard test conditions stc ptc is a more real world approach to measure the actual performance of a solar cell. Ptc is an acronym for pv usa test conditions which were developed at the pv usa test site at the university of davis california.

The value that interests us is the maximum power pmax or rated power pr which is the nominal power of a solar panel when you look to buy one. Pvusa test conditions ptc in the mid 1990s under the direction of the national renewable energy laboratory nrel a set of test conditions were developed to measure solar panel performance under real world conditions. It could also be called peak power. 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 a ptc value isn t given a good rule of thumb is that the ptc rating is about 10 15 less than the stc rating. Stc in an acronym for factory standard test conditions which is 1 000 watts per square meter solar irradiance 1 5 air mass and a 25 degrees c. Standard test conditions stc stc is used by solar panel manufacturers to test and rate their panels.

Ptc has been developed at the university of davis california. It specifies an irradiance of 1000 w m2 with an air mass 1 5 am1 5 spectrum and an ambient temperature of 20 c at 10 meters above ground level with wind speed of 1 m s. 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. The electric output of pv solar panels is measured under standard test conditions stc.

Ptc condition details and testing setup. Pv usa test conditions ptc ptc is an acronym for pv usa test conditions and is a us standard that was developed at the university of davis california. Finally since photovoltaic modules in the real world are exposed to wind ptc testing keeps the air moving at 2 2 mph. For example a kyocera 180 watt panel is 180 w under stc which means that this module will typically produce 180 watts under the irradiation of 1 000 w m2 at the cell and ambient temperature of 77 f 25 c and an air mass of am 1 5.

They are very important when more than one solar panel is to be used together in an array. In some states the ptc rating is the benchmark for calculating system rebates so it s an important metric to know.