Technology

It’s good to know that they have pretty good longevity. One thing complicating this is that panel technology has gotten better and better during that time. There’s a graph on Wikipedia plotting how much better the various types of panel have gotten since the 70s. A lot of them have doubled in output since the early 90s.

So on the one hand, these old panels are outputting 75% of what they started with, which is good. But on then other hand they are only outputting about 37% of what new panels could.

Not that we should throw old panels away. There’s plenty of sun to go around (though I guess the average homeowner only has one roof to use). It’s just interesting how fast the tech has improved and how that might factor in to some longevity calculations.

The weird thing is that in this scenario these panels are still applicable for replacement probably because the the solar panels of today compared to then are about ~40% more efficient. So compared to a new replacement it's at around 60% efficiency. A major site plans profit off of 30 years and plans to replace glass at that time, so while it may still be somewhat useful long term it's probably more profitable to replace them.

I doubt they put out much power at all compared to modern panels. Solar back then was a pipe dream, we didn't have the battery technology to store the energy and the panels had a lower voltage and could supply less current.

I have a 100w foldable panel for camping that at >= 20% efficiency is probably double what the 90s panels could do.

I'm getting some new panels installed this year, and I think they're suggesting they'll be at 80% after 25 years.

It looks like there is disagreement between the title and content of the article. Title says 75.9, content says 79.5

Either way, does this suggest that new panels might do better than expected over a 30 year timespan?

I thought that solar panels that old performed much worse or stopped working. Especially considering where the tech was in the 1990s.

Wow, imagine where we'd be if Oil and Gas hadn't convinced almost everyone that solar was never going to work well.

Sounds like you should install double what you think you need. Reason? The panels will start losing efficiency over time and your electricity usage over time will do nothing but grow. That's very common.

As far as I know that's nothing to write home about, monocrystaline solar panels get like ~30 years dropping down to 80% and then slowly begin to fail from there. I'm far from an expert, but my understanding is this is the norm and that if we found out they weren't lasting this long then people would be getting worried about a messed up cost calculous.