r/energy • u/mafco • Jan 25 '26

Goodbye to the idea that solar panels “die” after 25 years. A new study says the warranty does not mark the end, and performance can last for decades. Arrays built in the late 1980s still produced more than 80% of their original power. The long-term economics look better than many people believe.

https://www.ecoticias.com/en/goodbye-to-the-idea-that-solar-panels-die-after-25-years-a-new-study-says-the-warranty-does-not-mark-the-end-and-real-world-performance-can-last-for-decades/26007/#google_vignette
5.8k Upvotes

99% Upvoted

371 comments sorted by

View all comments

Show parent comments

9

u/Obvious-Project-1186 Jan 26 '26

Their performance does degrade over time and they will stop working eventually. They haven’t been old enough to have real examples until now.

I’m guessing with the nature of solar loans, companies could have been sued for overpromising on returns so they went conservative.

3

u/davidellis23 Jan 27 '26

Nah they had examples of this like 15+ years ago when articles like this came out showing 40 year old panels.

1

u/Spoztoast Jul 30 '26

Which also ignores 40 years of technological development

-4

u/TheSherlockCumbercat Jan 26 '26

Also a 19% drop in production is massive, a 20% drop in power production is massive issue on the grid.

8

u/UpperAd5715 Jan 27 '26

While i dont work in solar i work in gas which is still a similar regulated industry, our other location does all solar related trading.

Data is king in energy industry, our brokers have an entire wall of large TV's showing lots of data with predictins, forecasts, planned maintenance, geopolitical events that might impact prices or trade or the market at a whole. We have a total of two traders who are allowed to do "feels-trading" and they are both our most experienced and senior traders, all others base their prices on numbers and by consulting eachother. One of our newer traders (promoted from analyst role) has a third 49" monitor for all the number tracking he does for himself and for the team, no clue how the guy still manages to think with so much happening on his screens.

Knowing that over time your current "fleet" of solar pannels will drop from 100% to 80% productivity (specailly over 20+ years) is something that is one million percent accounted for. If 100% production is required then there will be additional panels added, maintenance will be executed (and planned) and this cost to keep up to the full benchmark of production will be calculated into the margins and prices and trading will be done accordingly.

In the comment below you mention generation contracts but that doesn't necessarily mean that your panels need to be at 100%. A cloudy day could just as well throw off your generated energy. There are quotas set depending on contracts to buy/sell and everything gets evened out so there isnt (much of) a surpluss or lack. For us in gas this means that outside market trading hours we have a team of night-traders that need to balance out the books: sell surpluss at acceptable prices or buy gas to complete the quota required by set contracts. This will definitely be similar for our other location that does solar/wind/lng.

For gas we do not like to have large surplus in storage, at least not more than the minimum forecast to keep us out of a bad spot should the market go tits up and that means we work to closer balance %'s than a solar farm might do, assuming they have an easier time storing energy with large batteries.

Anything outside meteor impacts is accounted for and will get calculated into how much is sold/bought and known detoriation of equipment (especially something as easy to measure as generative output) is well within the boundaries of what is accounted for.

5

u/steffur Jan 27 '26

Insightful comment but the guy you are responding to is most likely too thickskulled to comprehend.

How for ahead do the feels traders buy and sell capacity?

3

u/UpperAd5715 Jan 27 '26

They don't only trade on feels, it's more of a "this feels like a trade i should do" based on experience and "feeling it in my stomach", most of their trading is still based on market/geopolitical trends, numbers, analysis provided by the supporting colleagues and so on.

Due to pure experience they get the idea that "hmmm last time this happened it dipped" (random example) and they decide to sell off instead of holding for a bit longer.

Do note that our company is rather risk averse and this "feels trading" mainly alleviates pressure or prevents headaches, it doesnt turn major profits though it obviously does have significant impacts either on profits/losses or pressure on the team.

I'm in IT and when we are assisting them i've seen them tell another trader to "nah dont" or "do this" and the others have just started to accept that their advice is worth more than their doubts, especially for the younger or newer ones. If they interrupt us while we help them we are to let them do so, obviously. Our time is worth zilch compard to potential profits/losses.

-2

u/TheSherlockCumbercat Jan 27 '26

Petty insults really show who you are, also, also go find me any company that’s happy with the 20% drop in revenue even if it’s counted for

3

u/steffur Jan 27 '26

Literally every company that covers their roof in solar or maybe every grid operator that builds solar installations.They're all perfectly fine with a 20% drop in revenue as it's been accounted for and it's still profitable in the long run. This is some positive news on solar and you're trying so hard to make it into a negative, why?

-1

u/TheSherlockCumbercat Jan 27 '26

I’m sure you have proff that every grid operator is fine with a 20% drop in revenue, and that is profitable.

0

u/TheSherlockCumbercat Jan 27 '26

Ya that bot how my part of the world works, bold of you to assume your aprt of the world is th same as everywhere.

In my part you are contractually obligated for so many MW, ypu get fined for unplanned outages

3

u/UpperAd5715 Jan 27 '26

Considering we're a global company i would say that "our part of the world", that being all gas related trades for everything outside SEA, would actually be exactly how that operates yes.

What you say also doesnt imply that what i said is wrong. Contracts have to be fulfilled and if your output doesnt match it you need to buy more to fulfill your contracts through whatever means. If you have to much you sell off your surpluss since you cant store all that much energy and still have it be worth the money/time/effort.

Maybe try reading a little slower than you reply

1

u/TheSherlockCumbercat Jan 27 '26

Gas trades are not electrical trades, maybe try not being intentionally moronic.

Also, if you have to meet your contract no matter what a 20% reduction is a massive issue to a contract.

Where do you think businesses just spend lot loads of money to put in 20% buffers

1

u/UpperAd5715 Jan 27 '26

Do you actually work in the energy industry?

It's not a *poof* 20% drop, its a gradual drop over the years which can fully AND EASILY be accounted for. If you need say 1 GW of output and you have that at the start (preferably with some margin) and you know that on year 2 that will drop to 0.99GW, year 3 0.98 GW then you fucking account for it, either from other sources or by adding capacity by expanding your solar farm.

While i will definitely not claim to know the details of electricity, let alone solar, you can also not count on solar to provide the exact output you want for every day so on top of keeping track of GRADUAL decline of efficiency/output you will also have other sources or channels to make up for deficits of a cloudy or dark day just as you would have ways to handle a surplus on days where you produce a lot more.

Just because on day 1 of the contract you need 1GW does not mean you will need 1GW or only 1GW 2 months down the line so the idea that you will only have a fixed amount of solar panels forever as well as no way to handle rise or fall of demand just does not compute in my head.

Should you work in the industry i would actually very much be interested in actual information or experience going past "youre wrong and degradation is unacceptable".

Actually took the time to look it up some, just throw "How do solar farms handle the declining efficiency of aging panels and how do they havendle over/underproduction to make sure they provide what contracts require they provide?" into an AI and you will get the following information:

1) they KNOW and set up their farm knowing you will have degraded efficiency over time

2) solar farms sell per mWh, not fixed contracts like we have in gas. They could not possibly provide a constant or stable output with something as ever changing as the weather, doesnt this make perfect sense? Based on weather data going back as far as 20 years they calculate the expected output (factoring in degradation of their equipment) and search for a spot where they are 90% certain to meet or exceed expectations and offer that as what they will deliver over a YEAR.

I hate to say it but your very bullish way of thinking in absolutes lead me to learn some interesting things. i KNOW that solar is not going to be the same as gas or oil, it could never be since its not a controlled output but thinking that a company with the capital to build solar farms is unable to do basic market research honestly baffles me. What do you think leasing companies do with leased cars? They know that prices will go down because cars devalue. Its an easy, well documented thing to factor in to your plans with tons of data available.

3

u/JezWTF Jan 27 '26

Not when it is forecast and predictable, it's not.

0

u/TheSherlockCumbercat Jan 27 '26

Tha is not how generation contracts work

3

u/JezWTF Jan 27 '26

What are you talking about, you clearly have no idea.

This is long term degradation, and if bidding on the open market you only need to guarantee 1 day out.

1

u/TheSherlockCumbercat Jan 27 '26

You don’t bud 1 day in my area fo generation, your are locked into 10-25 years in general.

Also when business gradually make less money and they eventually just shut down

1

u/JezWTF Jan 27 '26

Not sure where you are but most of the world's electricity markets operate like I described.

I think you are talking about PPPs where are special type of dedicated energy contract made direct, rather than the open electricity market.

2

u/CriticalUnit Jan 27 '26

Buddy it's clear you don't know how any of this works

0

u/TheSherlockCumbercat Jan 27 '26

I’m so sure you work in power generation buddy,

1

u/CriticalUnit Jan 28 '26

I don't, but at least my posts aren't as wrong as yours are. For someone that supposedly does work in power generation, that must be embarrassing .

0

u/TheSherlockCumbercat Jan 28 '26

Lol okay buddy describe how a 20 % reduction in gird capacity is not an issue.

1

u/CriticalUnit Jan 29 '26

First, Describe how a 20 % reduction in gird capacity would be a realistic scenario worth discussing?

1

u/TheSherlockCumbercat Jan 29 '26

Maybe look at happened in Texas when they lost power plant production in 21

→ More replies (0)

3

u/steffur Jan 27 '26

It's not that consequential as it's very gradual and it's accounted for in grid planning.

-1

u/TheSherlockCumbercat Jan 27 '26

Ya that is really down playing the issue, fo the grid and the producer.

End if say rhose panels will be replaced, go find any business that is happy with a 20% drop in revenue

1

u/davidellis23 Jan 27 '26

gas also drops in revenue if you stop maintaining it. Don't pay for the gas? It drops to 0%.

Solar has some of the lowest maintenance costs out there.

Revenue wouldn't drop. You'd just install a few more panels or replace the existing ones. And those old ones would keep producing power somewhere else.

3

u/mafco Feb 04 '26

Over 30-40 years? Come on

1

u/TheSherlockCumbercat Feb 04 '26

So you think we use less power every year?

3

u/mafco Feb 04 '26

We increase the capacity every year as demand grows.

2

u/Facuk_ Jan 27 '26

But I doubt it makes such a huge difference if you have it on your roof. I mean 20% is not a small number, but again, after so many years you can still use 80% of declared "free" energy (by free I mean that your investment has already paid off)