pv magazine test: September 2022 Results

By George Touloupas

 

This article was originally published in pv magazine – November 2022 edition. Learn more about the pv magazine test here.


CEA’s Senior Director of Technology & Quality, George Touloupas, provides analysis of September 2022 energy yield results from the outdoor test field in Xi’an, China.

The first chart (Figure 1) below shows meteo station data (irradiance and ambient temperature) for September 2022. The average bifacial boost is 7.9%. Bifacial boost is defined as the relative advantage of the average specific energy yield of all bifacial products compare to the average specific energy yield of all mono-facial mono PERC products.

Figure 1: Daily temperature and irradiance data - September 2022

Figures 2 and 3 below show the relative specific energy yield comparison between different PV module technologies. Although, the top performer is Longi’s bifacial PERC module, the average specific energy yield of the bifacial TOPCon category leads over the average yield of modules in the bifacial PERC category.

Figure 2: Relative yield of different technologies - September 2022

Figure 3: Total energy yield - September 2022

Our test field only has one sample from Jolywood in the n-TOPCon bifacial category. As TOPCon modules become more prominent, we look forward to installing more samples to achieve a more representative yield comparison.

Table 1: Bifacial boost - June to September 2022

Notes on the energy yield measurements:

  • The energy yield comparison among various technologies, including bifacial boost, will be analyzed using products installed after the beginning of 2019.

  • The energy yield is given in Wh/Wp and calculated by dividing the energy produced by the module by the Pmax at STC of the module. This Pmax is the maximum STC power after a process of stabilization.

  • The results are grouped in categories, per module type.

  • The bifacial boost depends on many parameters: the bifaciality factor, the installation geometry, the albedo of the ground, and the sun angle and diffuse irradiance. The ground in this case is gray gravel.

Table 2: Energy yield ranking - historical - June to September 2022

 

Test Cooperation

pv magazine test is a cooperative effort involving pv magazine, APsystems, CEA, and Gsolar. All testing procedures are carried out at Gsolar’s test laboratory in Xi’an, China. CEA supervises these tests and designed both the indoor and outdoor testing procedures.