Solar Panel Longevity: 2 Year Update

Often our customers ask “How long can the panels stay in the sun before I should take them down?” Sure the technical answer is that the panels can last 8-10 years in the sun without any discoloration or loss of power, but would it really stand up to a real-world test?

After a quality control test spanning two years, the longevity results are in and they are a resounding yes! Several years ago we placed a single 2 Watt Panel on the roof to see if it’s color, materials, or power output might fade over time. It was placed in clear direct sunlight through hot summers and snowy winters. We are proud to say that after a light scrub to remove the dust off the panel, the panel produced the exact same amount of power and looked nearly identical to itself before the test began.

2W Solar Panel is still clear with the same power output after 2 years in the sun

The real test of longevity isn’t the aesthetic of the panel though, it’s the output of the panel. We plugged it in to the same type of V11 battery that we originally tested the panel on, and were thrilled to see that the power output was nearly identical to the original power.

As you can see, the power of the panel was about 1% more today than when we began the test in 2011. That could be because the panel was angled slightly different at the sun in both tests, or the hot summer temperatures slightly lowered the output of the panel. You may be wondering why a 2W panel is only producing 1.5W, and that’s because when connected to a load device (such as a battery) the voltage of the panels will drop down to the voltage of the battery. This is explained more in this blog post.

Voltage and Current output after 2 years in the sun

How can it last so long? Unlike other companies who use low-quality materials that degrade in the sun (solar panels that degrade in the sun….let that sink in) we refuse to use anything other than the highest quality materials on the market. For solar panels, that means covering them in UV resistant urethane. Unlike other types of resin epoxies, urethane does develop a cloudy or yellow color. It is also far more durable than panels laminated in cheap plastics that deteriorate in the sun and detach from the rest of the solar panel, which is common in the grand majority of solar folders and standalone solar panels on the market.

Whether you are a Peace Corps Volunteer looking for the most durable panels on the market, or a DIY hacker making her own Arduino project that will stay outside for months at a time, or an outdoor adventurer who needs gear that can withstand the harshest environments, you can have the confidence that these are the toughest small solar panels you can get.

Two Brooklyn winters and still going strong