Solar panel testing and certifications overview

Like other electronics, solar panel modules undergo rigorous testing before installation. These tests are critical to determining the quality and performance of panels under particular environmental stresses and confirming they meet mandated safety requirements. In this article, we'll review today's most common testing and certifications for solar panels.

Solar panel testing is crucial in ensuring a module's quality and safety. Solar panels have a long lifespan: properly built and installed equipment should generate usable electricity for over 25 years. Given the longevity of your investment, you want to ensure that any equipment on your roof will perform well and operate safely on your roof.

With solar becoming increasingly popular, many states, local governments, and utility companies have created new mandates requiring any grid-tied solar equipment to hold specific certifications. The same holds for some solar incentive programs; if you're participating in a state-funded incentive program, don't be surprised if they have particular testing or certification requirements for your equipment.

While reviewing a solar panel spec sheet, you'll likely notice a bunch of acronyms and random numbers listed under safety and rating certifications – what do these mean? Below are some of the most common solar panel testing standards and certifications to look for when comparing solar panels:

IEC: International Electrotechnical Commission

The IEC is a nonprofit establishing international assessment standards for electronic devices, including photovoltaic (PV) panels. Notably, the IEC does not test or certify panels themselves – they set the standards for other testing facilities to follow.

IEC 61215: Standards for crystalline silicon terrestrial PV modules

IEC 61215 is one of the core testing standards for residential solar panels. If a solar panel module successfully meets IEC 61215 standards, it completed several stress tests and performs well regarding quality, performance, and safety.

IEC 61215 standards apply to monocrystalline and polycrystalline PV modules, the most common types of solar panels. The IEC sets different testing standards for other solar electric technologies, such as thin-film solar products (IEC 61646).

Solar panels that meet IEC 61215 standards are tested on the following (and more!):

• Electrical characteristics (wet leakage current, insulation resistance)

• Mechanical load test (wind and snow)

• Climate tests (hot spots, UV exposure, humidity-freeze, damp heat, hail impact, outdoor exposure)

IEC 61215 tests also help determine a panel's performance metrics at standard test conditions (STC), including temperature coefficient, open-circuit voltage, and maximum power output.

IEC 61730: Standard for PV module safety

As with any electronic device, solar panels risk electrical shock if improperly built. That's where IEC 61730 comes in: this standard address the safety aspects of a solar panel, encompassing both an assessment of the module's construction and the testing requirements to evaluate electrical, mechanical, thermal, and fire safety. PV modules that successfully pass IEC 61730 tests run a low risk for these types of hazards.

IEC 62716: Ammonia corrosion testing of photovoltaic (PV) modules ammonia corrosion

Do you live on or close to a farm? If so, keep an eye out for IEC 62716 – this is a test to determine a module's resistance to ammonia. While most people don't have to worry about their high concentrations of ammonia exposure with their PV modules, installing your solar panel system close to farms and livestock can be a concern. Ammonia corrosion can accelerate degradation in a panel, leading to lower overall electricity production over the lifetime of your system.

IEC 61701: Salt mist corrosion testing

If you're lucky enough to install solar panels on a beach house, it's worth checking to see if your prospective solar panels have successfully passed IEC 61701 tests. With these tests, panels undergo a series of salt sprays in a controlled environment. After the sprays, testers inspect the modules for physical damage – such as corrosion or delamination– and assess their electrical output and overall performance. Panels that successfully pass IEC 61701 tests are a suitable choice for beach-front solar panel systems or systems near roads experiencing high levels of salting in the winter.

IEC 60068-2-68: Blowing sand resistance testing

Some solar panels undergo IEC 60068-2-68 testing to determine how well they hold up in sandy desert environments. Frequent exposure to abrasive sand can wear a panel down, leading to physical or mechanical defects over time. If you're installing solar in an area that sees frequent sand or dust storms, try choosing a panel that successfully passed these tests to maximize the durability of your system.

Outside of IEC, UL is the other most common acronym on a spec sheet related to solar panel testing. This stands for Underwriters Laboratories (UL), a global safety certification company based in the United States. They provide testing services and certifications for many products, including electric appliances, industrial equipment, and plastic materials.

UL 1703: Standard for flat-plate PV modules and panels

UL 1703 is an industry-standard attesting to the safety and performance of solar panel modules. Similarly to IEC 61215 or 61703 tests, panels with this certification undergo simulated climatic and aging tests and have been deemed safe regarding mechanical loads, fire, and electrical hazards.

You may find that a solar panel spec sheet lists UL 1703 and IEC 61730 under safety certifications; this is pretty typical for any solar panel sold worldwide. UL 1703 is a mandate for solar panels sold and installed in North America. IEC 61730, on the other hand, is internationally recognized for safety standards and is more widely applicable to the global solar market.

UL 61730: Photovoltaic module safety qualification

UL 61730, a more recent addition to solar panel testing and certifications, combines the testing procedures and standards of UL 1703 with IEC 61730, allowing for complete international approval regarding a panel module's safety and performance.

It will become increasingly common to see this certification over time–as opposed to both UL and IEC–because it is often the more cost-effective option for manufacturers. To complete solar panel testing, manufacturers must provide multiple samples. For companies that plan to sell in both North America and international markets, completing UL 61730 testing reduces the number of panel samples needed, reducing testing time and costs.

Are you shopping for solar equipment that meets the above certifications and more? Head over to the EnergySage Buyer's Guide, where you can compare different types of equipment based on efficiencies, warranties, and more. On each product page, we've listed the passed tests and certifications for each panel so that you don't have to do the work of digging through spec sheets! Once you're ready to see offers from local installers, sign up on the EnergySage Marketplace to receive free online solar quotes from local installers.