Solar Nerd articles about: Reliability

When solar panels get hot, they become less effective at generating electricity. This is because as temperature increases, electrical resistance increases too. This means that as a solar panel gets hotter, more and more of the electricity it generates is lost as heat. It’s possible to know exactly the effect of heat on your solar panels by checking its specification sheet and looking up the power temperature coefficient. It’s expressed as a percent reduction of efficiency for every one degree Celsius increase in temperature.

Installing solar panels on your house is a pretty big investment - one that you’d like to last as long as possible. So how long should you expect your home solar array to last? Conventional silicon solar panels that are designed for a rooftop or utility installation can be expected to last 25 years. Some of the top brands come with 25 year product warranties, in which case you can consider 25 years to be the minimum lifespan.

Solar panels don’t have any moving parts. They just quietly sit on your roof or in your backyard for a couple decades and generate electricity, day in and day out. How cool is that? A study by the National Renewable Energy Laboratory shows that new solar panels have a failure rate of only 5 in 10,000 per year. This means that every year, a solar panel has a 0.05% chance of failing, or a total 1.

Adding solar panels to your home is a long term investment. But for that investment to work out, your solar equipment needs to last. One question people often have is: do solar panels wear out over time? The answer is that solar panels have a limited lifetime, and they wear out and lose efficiency as they get older. There are two ways this can happen. The first is a small loss in power generation each year as the solar cells in the panel degrade due to exposure to UV light and the elements.

If you’re going to drop a few thousand dollars on anything - a car, a saltwater aquarium stocked with Clarion Angelfish ($2,500 each!), or solar panels for your home, you want to make sure that your investment is going to last. Cars come with warranties, but expensive fish do not. Fortunately, solar photovoltaic equipment does come with warranties. However, even if a failure is covered by a warranty, the labor to replace it may not be, plus there’s the downside of losing power generation while waiting for a repair.