Intersolar Europe, a worldwide prestigious exhibition for the solar industry, was open in Munich, Germany from June 14 to 16. Yingli Solar met with a special visitor at its booth A2-270: a representative from PVEL, an international third-party testing agency. It was the second visit by PVEL to Yingli Solar at an expo, following the one at SNEC in Shanghai, where PVEL awarded Yingli Solar the global "Top Performer". The representative on behalf of PVEL once again expressed their appreciation and praise for Yingli Solar’s modules by using two words to describe the quality of the modules demonstrated in tests: “excellent”, “incredible”, and using one expression to describe Yingli Solar: “one of the few manufacturers)”.

Why has Yingli Solar gained so much praise from the most authoritative third-party testing agency in the world?

Let’s take a close look.

Generally, PVEL performs 8 extreme tests on the subject modules in accordance with standards stricter than those of IEC. For example, the standard for the thermal cycling testing is three times stricter than that of IEC. Specifically, modules should be subject to eight PVEL tests as follows:

1. TC: Thermal cycling test, according to the standard three times stricter than that of IEC.

2. DH: Damp heat test, according to the standard twice stricter than that of IEC.

3. MSS: Mechanical stress sequence, which will test the quality of modules under dynamic and static loads.

4. Hail: Hail stress sequence. IEC generally tests the products with hails at a diameter of 25mm, but PVEL uses hails at a diameter of 50mm. Under such harsh testing conditions, Yingli Solar is “one of the few manufacturers that have passed this test”, PVEL was quoted as saying.

5. PID: 192 hours for the standard of PVEL, stricter than the standard (96 hours) of IEC.

6. LETID: Light- and elevated temperature-induced degradation, according to the standard stricter than that of IEC.

7. LID: Light-induced degradation, according to the standard stricter than that of IEC.

All of the above 7 tests are intended to test the reliability of the modules under extreme conditions, and only those with efficiency attenuation not greater than 2% are deemed as winners. Yingli Solar's modules passed the above 7 tests successfully with an attenuation rate much lower than 2% in each of them, or even only 0.04% in a test.

That is not the end of the story.

Here comes the most marvelous part.

PVEL conducts a PAN test on the modules, where it simulates the power generation at two typical locations through PVSYST, and only BOMs in the top 25th percentile will enter the white list.

Yingli Solar's modules not only passed those 7 rigorous tests, but also ranked in the top 25th percentile among all tested modules in terms of power generation.

How difficult will it be for a manufacturer to succeed in all these eight tests? Data showed that out of all 35 test applicants around the world, only 5 of them passed all these 8 tests, and Yingli Solar was one of them!

You may check the testing outcomes of these leading manufacturers by visiting the PVEL’s official website at //www.pvel.com/.

Behind Yingli Solar’s success in such high-level tests are persistent scientific research accumulations and quality control efforts in the past 25 years. Well proven in numerous photovoltaic cycles, products of Yingli Solar have been widely acknowledged by global customers. Chinese users stated that Yingli Solar’s products have been efficient and safe for over 20 years, while international customers were impressed by the high quality and fine durability of the modules.

Reliable functioning and customers’ satisfaction are the most persuasive proof of product quality.

Time tells everything. Yingli Solar is customers' unwavering choice for the past 25 years!