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Even though we all want our solar installations to last more than 25 years, poor product design can have a major impact on how long the solar panels can last in the field.

Here is an illustration by PVEL and IEA-PVPS that outlines the failure mechanisms of a solar panel.

common solar panel defects
Common failure mechanisms experienced by solar panels.

Different failure mechanisms are caused by different panel components and occur at different times.

In this article, we explore 9 ways that WINAICO uses extensive quality testing to eliminate common failures in product design, improve component selection, fine-tune production processes, and make solar panels more reliable.

Thermal Cycling (TC) eliminates early component failures

As day and night cycles each day, and the weather changes throughout different seasons, Thermal Cycling works by putting solar panels through temperature extremes to simulate the impact of weather.

Solar panel components can expand and contract during Thermal Cycling, so weaknesses in laminate adhesion are tested, while poor soldering joints are exposed.

The temperature range of -40°C to 85°C is cycled for 600 cycles by WINAICO’s standards, 3 times the IEC 61215 standards, to make sure our solar panels can perform better and longer.

Damp Heat (DH) tests waterproofing to the extreme

Solar installations usually associate with tropical and subtropical regions that get plenty of the sun to amplify solar energy.

While Damp Heat can help recreate the stresses of tropical climate, it can also test how well the module laminate can protect solar cells from water, condensation and dirt.

WINAICO’s panels are put through 3000 hours inside the chamber at 85°C and 85% relative humidity, 3 times the IEC standard, to test the strength of EVA, backsheet adhesion, and the insulation of double-sided tape and the junction box.

solar module environmental chamber
Damp Heat test is conducted inside a temperature and humidity controlled chamber.

Unlike most other solar panel brands that use silicone gel, WINAICO only uses double-sided tape to insulate the laminate before framing.

Silicone gel is notoriously unreliable as long term insulation, as the gel would stiffen and lose adhesion with frame and glass after a few years.

Solar panels framed with silicone gel would deteriorate quickly after Damp Heat tests.

Mechanical Loading (ML) tests solar module endurance under constant pressure

WINAICO solar modules are built to operate almost anywhere in the world, including places known to experience heavy snow during long winters.

The Mechanical Loading test puts the solar panels in uniform constant pressure on both the front and rear sides in an alternating fashion to simulate the stress of heavy snow.

The result is a test of strength for solar glass and frames and how well they can protect solar cells from cracks.

Our test partner uses a giant bag filled with water to simulate the stress of 5400 Pa on the solar panel and use EL and flash tests to confirm the before and after power degradation is within the IEC standard of 5%.

Hail Impact tests the strength of solar glass

Most continental solar installations at mid-latitudes are sure to experience a few hailstorms during their 25 year lifetime.

So we subject our panels through the impacts of multiple ice balls with 35 mm diameter that travel at 100 km/h to make sure the reinforced glass can protect solar cells in a severe hailstorm.

ice ball solar module hail impact test
35 mm diameter ice balls are used to simulate the impact of hailstones.

The 35 mm ice balls have 4 times the kinetic energy of the 25 mm, 83 km/h hailstone test by IEC, making our solar panel a leader in surviving hailstorms in the field.

Potential Induced Degradation (PID) test confirms our modules can be installed in long module strings

As long solar module strings can reduce conduction losses due to lower currents, the increased system voltage can lead to PID degradation in solar cells.

WINAICO’s solar panels are tested to IEC TS 62804-1:2015 with 1000 V system voltage at 85°C and 85% relative humidity for 96 hours, to confirm our component selection can withstand the stress of high system voltages without deteriorating the solar cells’ energy production.

So our customers can feel confident in connecting our panels up to the rated system voltage without being damaged by PID.

Light and elevated Temperature Induced Degradation (LeTID) shows a new way for PERC cells to deteriorate

LeTID is a defect especially prominent in PERC solar cells that can decrease power output up to 10% after installing the panels.

By placing our solar panels in 75°C chambers with a low input current for 162 hours/cycle and multiple cycles, we can detect the impact of LeTID in component selection.

WINAICO solar panels are tested to eliminate LeTID as a failure mechanism for our panels in the field.

Dynamic Mechanical Load (DML) to simulate the effect of strong wind

Our solar panels can be found in windy regions around the world, and we put the panels through severe DML criteria according to IEC TS 62782:2016 to test the panel resilience against strong winds.

dynamic mechanical load solar panel
DML test equipment to alternate up and down pressure of 1000 Pa.

Our panels are subject to 1000 cycles of push-pull stresses at 1000 Pa to demonstrate the glass and frame can survive in windy regions.

Salt Mist test to make sure panels can work at coastal areas

Solar panels can help a coastal holiday home become carbon neutral, and thus we test our modules against the corrosive salt mist (IEC 61701:2020) to prove their toughness against seawater.

salt mist solar panel reliability test chamber
WINAICO panels undergoing salt mist test conditions.

Our products go through a Severity 6 Salt Mist test at 40°C, 90% relative humidity chamber to make sure saltwater vapour cannot enter the module backsheet and cannot corrode the module frames.

Ammonia tests to show panels can work in farms

Agricultural solar applications are a great way to increase the earning potential of vast farmlands.

A special provision of the solar panel needs to be made against the corrosive ammonia created by farm animals, so the solar panels can maintain high performance for 25 years.

WINAICO solar panels undergo 480 hours of ammonia test according to IEC 62716:2013 with 20 temperature cycles between room temperature to 63°C.

This way, we can confirm our module components, including glass, backsheet and frames do not deteriorate in ammonia and impact power output.

So our solar panels can perform well in farm applications throughout their 25 year lifetime.

To learn more about how WINAICO solar technologies can help with your rooftop energy production, please get in touch with us.