The key to photovoltaic module efficiency: Exhaustive testing and quality standards.

Standard or norm, it is not the same thing 

Our industrialized world is becoming increasingly complex and sophisticated. We use hundreds of products, which we cannot produce with our own hands. Therefore, we have to rely on the manufacturer's good work, with the aim of utilizing the product for as long as possible and without assuming any safety risk. 

To achieve this, we make use of an infinite list of standards and norms ... And practically all the products and services we use on a daily basis follow one guideline or another. In general, we consider standards those voluntary guidelines agreed upon by the group of people and institutions involved in using the product, while the application of norms is considered mandatory. 

The photovoltaic world also follows this system. For example, the Low Voltage Regulation is a regulation, which is compulsory for any photovoltaic installation < 1500V in Spain. In terms of standards, the most important for the sector are the IEC. 

IEC, the great photovoltaic watchdog 

The IEC (International Electrotechnical Commission) is a global NGO based in Geneva, Switzerland. Its mission is the constant development of standards. It encompasses 170 countries, and more than 20,000 experts work on its technical committees. Membership is open to countries, but not to companies or individuals. However, the latter can work in Technical Committees (TC), which exist for any product group. In Spain, the Technical Committee for photovoltaics is called "TC 82, Sistemas de energía solar fotovoltaico [Photovoltaic solar energy systems]".  Experts from the entire range of companies and institutions, from manufacturers to universities or distributors such as Amara Nzero, work on the committee, in connection with all the other international committees. Its sole objective: to develop standards to make photovoltaic components safer and more durable. 

The sale of modules that do not comply with these "internationally recognized standards" is not prohibited, but it is very rare to find a panel that does not comply with them. 

Parent standards 

There are a large number of IEC standards that apply to photovoltaic modules, but there are two that clearly stand out and fulfill basic functions: IEC 61215 and IEC 61730. It is not impossible, but very rare that a module does not meet these standards, as we usually confirm in the module datasheet and as we can see in the following image: 

IEC 61215 - the mother standard 

The goal of standard IEC 61215 is to pursue the module's durability. To this end, it provides for a series of tests that must be passed by samples a manufacturer sends to a recognized independent laboratory. After successfully submitting the modules to the tests described in the standard, the laboratory issues a certificate confirming this, which the manufacturer uses to demonstrate the good quality of its product. Here are detailed requirements such as the characteristics of the individual module label, assembly instructions, as well as a series of 19 different tests they have to pass. There is a broad range of tests: measurement of maximum power, outdoor exposure, humidity, heat or freezing, among others. Each assay is given an acronym beginning with MQT. For example, MQT 16 is a test of resistance against mechanical loads. Here we see how it works:

Another test, MQT 6.1, describes how peak power is measured under standard conditions (STC): 

MQT 17 describes the hail test, where ice balls are dropped on the panel:

IEC 61730 - the father standard 

While IEC 61215 focuses primarily on durability, IEC 61730 elaborates on operational safety; the two are closely linked. 

Here, we find determinations on aspects such as insulation, connectors or diodes. Like IEC 61215, here too the panel is subjected to more than 30 different tests, including pass/fail criteria. In this case, each test is prefaced with the acronym MST. It covers tests such as material thickness, insulation of live parts, shear susceptibility, among others. 

The following video shows the flammability test:

The next test, MST 32, verifies resistance against breakage, as shown in the following video:

Conclusions 

Operating photovoltaic plants without the application of international standards, such IEC standards, is possible, however, it would pose a serious danger to the installation's performance and safety. 

Despite the benefits of the standards, they all have a considerable disadvantage: they test a module at the beginning, but do not provide information on how it will behave in 15 or 20 years.  Accelerated degradation tests are performed , but the ultimate test is the operational and long-term test. Problems such as PID or LeTID arose in modules in the field, even though they had passed the pre-trial tests. 

Standards ensure the success of a PV plant, but are not a guarantee against defects or underperformance. 

The modules used in Spain usually comply with the two standards described here, but there are many more, such as resistance against ammonia, sand, transport rules, etc. One of the first tasks of the module buyer should be to check the certificates of the module of interest. It is worth saying: the more the merrier for everyone's peace of mind. 

Amara NZero 

Amara NZero offers the installer an extensive range of tutorials, training courses, blogs on how to install and maintain a photovoltaic plant, so that it operates at optimal condition for 30 or more years: https://amaranzero.es/academia. 

Quality pays off in the long run, in terms of both money and safety. Using the best equipment, installing it properly and performing optimal maintenance are two sides of the same coin and should be part of the DNA of all PV installers. There is abundant free information on the Internet. If you have questions, there is a very fast and efficient way to get an answer: consult Amara NZero!