There aren’t too many things that we bought in 1980 that are still functioning just as they were when new, much less in existence. This might be a good time to check your warranty, if you still have something like a solar installation on your roof or land.
Any good company will have a decent warranty covering their products, hopefully at close to the lifespan of the product. Solar panels typically last between 20 and 40 years, and warranties can vary, but ought to be somewhere close to the minimum expected lifespan.
Martin Halloway, a designer of environmentally friendly buildings, recently decided to take down one of his solar panels to check out its performance. The ARCO 33 W solar panel was purchased in 1980, which makes it over 30 years old now. Halloway tested it using a couple of real loads, such as a 4.5 A blower, and a 35 W bulb.
Performance was measured right around the panel’s 33 W rating. The blower drew 2.5 A at 14.8 V, calculating to 37.2 W, while the bulb drew 2.0 A at 14.9 V, a 30 W draw. ARCO Solar, now SolarWorld, explained that solar panels have an efficiency curve proportional to temperature.
Halloway’s testing day was 50°F in full sun, which helped the solar panel generate more electricity. Even so, after 30 years in service, it is good to see something still working as it was designed.