Solar panels installed in France in 1992 found to retain a remarkable 79% of original output

[zohaibahd]

Why it matters: Solar panels are meant to last for decades, with an estimated operational lifespan of 20 to 40 years. However, their efficiency and the ability to generate power will degrade over time. Surprisingly though, a new long-running test in France paints a positive picture of the longevity of solar panels in the wild.

In 1992, a small 1-kilowatt solar array called Phébus 1 was connected to the French grid by Hespul, a nonprofit renewable energy association based in Lyon, France. Over 30 years later, that same installation is still pumping out watts. After dismantling the vintage 10 square meter array last year, technicians ran the panels through rigorous lab testing per international standards and found astonishing results.

An average of 79.5 percent of the initial rated power output was still being achieved after 31 years of service. Solar panel manufacturers typically guarantee only 80 percent of original performance for up to 25 years. Phébus 1 blew right past that metric, with the decline coming in at just 0.66 percent per year on average over its 31-year lifetime.

For example, on the installation's 20th anniversary in 2012, the panels still cranked out 91.7 percent of their rated output. The drop-off has accelerated somewhat in more recent years for a portion of the modules. After 31 years, the modules have produced 20,366 kWh for 882 Wp, or 745 kWh/kWp/year.

"These results confirm those of various scientific studies that are references on the subject," Hespul concludes.

The association cites a long-term Swiss study and recent American and European research showing median solar panel degradation rates from 0.36 to 0.75 percent annually. So, while declines in output are inevitable as the years go by, this real-world data demonstrates solar installations can keep on trucking for a few decades, remaining at highly viable performance levels.

This longevity bodes well for residential rooftop arrays and the overall transition to cleaner electricity generation sources.

A report from Ember, an independent global energy think tank, also has some sunny news on that front. The organization's latest Global Electricity Review shows renewable sources like solar and wind reaching new records in 2023, accounting for over a third of worldwide electricity generation. Solar saw a 23-percent year-over-year growth rate, while wind expanded by 10 percent.

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Solar panels installed in France in 1992 found to retain a remarkable 79% of original output

 

[scavengerspc]

Great write up Mr. Ahmed, and this has been covered here before but to minimal effect.
There are still people here that believe a panel is near useless after 7–10 years (The old break even point.)

And it does look to be that panels in the last decade or so may result in a slightly less life expectancy, though they still guarantee them for 30 years. It looks like higher output\efficiency was gained, but with a loss in longevity.

I know the panels I installed on an out building in 2011 are down to about 87% efficiency, though have been holding there for 3 years now.
But I expected a loss over time, and overprovisioned a bit.

 

[opckieran]

It would have been neat if they did this more frequently to better visualize any exponential decay in performance loss. Still, great results nonetheless. 20% longer than 25 years to 80%, and still operating over 91% at 20 years is excellent. Especially considering how prices have fallen since the early 90s.

 

[VitalyT]

That's why Perovskite may never gain any significant traction, being both expensive and volatile.

 

[kiwigraeme]

Panels on houses is becoming a no brainer for most situations, especially as EVs ramp up.
Just beware std setup , no power if grid goes offline, to stop electrical workers getting shocked as you feed power back into grid.

Must really be a no brainer where gets really hot, as max sun and air conditioning will be running hard

 

[WhiteLeaff]

Yeah, but haters will continue to lie about solar panels degrading prematurely...

That's why Perovskite may never gain any significant traction, being both expensive and volatile.

A chinese company started marketing perovskite panels, the warranty and life expectancy is similar to that of silicon panels according to them.

'Yu said the panels have passed all IEC testing for solar modules and can withstand a 2,300-hour UV bath at 1,000 watts per square meter and 60 C, for 12 years of operation without degradation. He said the company has been developing perovskite technology since 2018 and has solved the early degradation problem. It offers a 10-year product warranty and a 25-year warranty on linear degradation.'

https://www.pv-magazine.com/2024/06/13/commercial-perovskite-solar-modules-at-snec-2024-trade-show/

 

[VitalyT]

Yeah, but haters will continue to lie about solar panels degrading prematurely...

A chinese company started marketing perovskite panels, the warranty and life expectancy is similar to that of silicon panels according to them.

'Yu said the panels have passed all IEC testing for solar modules and can withstand a 2,300-hour UV bath at 1,000 watts per square meter and 60 C, for 12 years of operation without degradation. He said the company has been developing perovskite technology since 2018 and has solved the early degradation problem. It offers a 10-year product warranty and a 25-year warranty on linear degradation.'

https://www.pv-magazine.com/2024/06/13/commercial-perovskite-solar-modules-at-snec-2024-trade-show/

I reckon they are not planning to be around by the time the warranty fails, like so many Chinese businesses, I wouldn't trust their claims.

 

[p51d007]

Any idea if those in France are subject to the storms we have in the midwest? We have spring/summer HAIL STORMS which might impact (on pun intended) the survivability of the panels.

 

[toooooot]

They are most likely so ineffective that using them is pointless.

 

[Aaron Jones]

I know the panels I installed on an out building in 2011 are down to about 87% efficiency, though have been holding there for 3 years now.

You are confusing efficiency with rated output.

Almost every residential solar panel you'll find has an efficiency rating in the 20% ballpark; meaning that 20% of the solar energy captured is converted into electricity. Degradation per year is in terms of rated output, and your panels are down to 87% of their rated output. 87% of 20% is 17.4%, so your panels are down to the ballpark of 17-18% efficient.

 

[scavengerspc]

You are confusing efficiency with rated output.

Almost every residential solar panel you'll find has an efficiency rating in the 20% ballpark; meaning that 20% of the solar energy captured is converted into electricity. Degradation per year is in terms of rated output, and your panels are down to 87% of their rated output. 87% of 20% is 17.4%, so your panels are down to the ballpark of 17-18% efficient.

Ok brother. The nits have been picked.
A stat my system can give me is total output, which dropped to 87% of the output of 11 years before when I installed them, so I posted that.
3 years later (now) it is still producing that 87% of its 2011 production. What I care about is output at similar sun levels, which it calculates as solar irradiance.
Forgive me, but did you notice everyone else knew what I was saying?

 

[Uncle Al]

Excellent article ....

 

[Endymio]

It's worth noting that these panels were installed not far from Paris, at a latitude of nearly 49 degrees N -- further north than Canada's Halifax, Nova Scotia. That reduces the solar insolation the panels receive, reducing their effectiveness -- but it does mean they last longer. Both greater solar flux and higher ambient temperatures increases the rate of degradation of solar panels.

 

[lonetac]

I dont understand folks resistance to solar power.

Our panels have us relying on the grid for 18% of our power and we havent paid one cent to the electric company since turning the system on.

Its viable for a good portion of suburbia in america and is a no brainer for reducing our reliance on fossil fuels. It wont eliminate the need but it reduces the reliance on it.

Our system will amortize itself in 6 years. The panels will be producing energy for 20-30 years.

 

[GodisanAtheist]

I dont understand folks resistance to solar power.

Our panels have us relying on the grid for 18% of our power and we havent paid one cent to the electric company since turning the system on.

Its viable for a good portion of suburbia in america and is a no brainer for reducing our reliance on fossil fuels. It wont eliminate the need but it reduces the reliance on it.

Our system will amortize itself in 6 years. The panels will be producing energy for 20-30 years.

-I got a new roof, about 2 years old. Not in a rush to go punching a bunch of holes in it getting an array installed.

Not fundamentally opposed to the tech though.

 

[lonetac]

-I got a new roof, about 2 years old. Not in a rush to go punching a bunch of holes in it getting an array installed.

Not fundamentally opposed to the tech though.

We actually had a new roof put on for the purpose of getting solar.

If you have an old roof, you put yourself in the situation where when you need a new roof, you have to take the panels down, replace the roof and then re-install it costing you 1000s.

When you do both at the same time, its in a situation where it doesnt need to be touched for 30 years.

We got a GAF gold certified roof and installing solar is 100% covered and does not invalidate the roof warranty. They actually encourage it!

Just some food for thought. You obviously do what you think is best. Its not really the equivalent of punching holes through it though, the roof is solid even with solar attached. We get a lot of rain here in CT.

 

[Endymio]

I dont understand folks resistance to solar power.

Our panels have us relying on the grid for 18% of our power and we havent paid one cent to the electric company since turning the system on.

This is true only because (a) you used a huge portion of other taxpayer's dollars to fund your system, through federal, state, and (possibly) local tax credits and incentives. And more importantly, (b) because you're increasing your neighbor's electricity bills, through mandates that force utilities to purchase excess power from you at above-market rates, whether or not they actually need it.

It's a nice racket ... but one that works only as long as a small percentage of the population engages in it. And even then, it doesn't work for people who live in apartments, or in homes in areas with low solar insolation due to high latitude, cloud cover, and/or nearby trees or tall buildings.

 

[gamerk2]

Panels on houses is becoming a no brainer for most situations, especially as EVs ramp up.
Just beware std setup , no power if grid goes offline, to stop electrical workers getting shocked as you feed power back into grid.

If only there were some way to put a switch between the grid and the house if no input voltage is detected, like some form of switch...

 

[gamerk2]

This is true only because (a) you used a huge portion of other taxpayer's dollars to fund your system, through federal, state, and (possibly) local tax credits and incentives. And more importantly, (b) because you're increasing your neighbor's electricity bills, through mandates that force utilities to purchase excess power from you at above-market rates, whether or not they actually need it.

(a): Disregarding all the Federal/State/Local tax credits that go to legacy forms of power generation?

(b): Shouldn't excess power generation into the grid *lower* prices due to the whole "more supply, less demand" thing?

 

[Endymio]

Shouldn't excess power generation into the grid *lower* prices due to the whole "more supply, less demand" thing?

Glad you asked. Electricity is not like crude oil or soybeans -- you can't simply put extra capacity into a big barrel somewhere and wait to use it. The largest problem utility firms face isn't generating the energy -- it's matching supply to demand in real time, second-by-second ... and too much power is just as bad as too little. When a residential yahoo injects excess power into the grid when supply is already high, it doesn't save the utility money, it actually costs them. It typically happens when the utility's own wind and solar sources are out-producing, and, since cheap baseline sources like nuclear and hydro can't respond quickly enough, it forces the utility to maintain huge batteries of quick-responding natural gas plants.

On a side note, this explains why Germany's natural gas consumption has increased dramatically, as the attempt to generate even more and more electricity from 'green' sources.

(a): Disregarding all the Federal/State/Local tax credits that go to legacy forms of power generation?

On a per-energy dollar generated, wind and solar receive anywhere from 50x to 500x the tax credits and subsidies that fossil fuels receive. More importantly, credits given to oil and gas are almost entirely done not to simply "support" those industries, but to force them to run their business in a manner the government deems more socially, environmentally, or (even yes) racially just.

 

[lonetac]

This is true only because (a) you used a huge portion of other taxpayer's dollars to fund your system, through federal, state, and (possibly) local tax credits and incentives. And more importantly, (b) because you're increasing your neighbor's electricity bills, through mandates that force utilities to purchase excess power from you at above-market rates, whether or not they actually need it.

It's a nice racket ... but one that works only as long as a small percentage of the population engages in it. And even then, it doesn't work for people who live in apartments, or in homes in areas with low solar insolation due to high latitude, cloud cover, and/or nearby trees or tall buildings.

My neighbors bills are not impacted by my solar system. Thats conjecture and its not true. Eversource is a wracking millions of profit every year (1/2 billion I believe).

Tax credits and incentives are just that, tax credits and incentives. Taxpayers dollars are used everyone, you really dont have any sort of gotchya there or valid point that I can see. I remember you trying to compare it to stealing and attacking my character over it which is just a gross exaggeration. The power companies and every business in this world uses tax incentives every chance they get. So should you.

You are kind of stupid to not use tax incentives to do something that is being encouraged. Incentives are there because science backs it and they are encouraging adoption. Thats how incentives work. When you have a higher adoption rate, you can lower any incentives. Even without the incentives, its a no brainer. We wont be paying for electricity for 30 years. The cost of the system is far less than what that power would be coming from eversource over the same time period. In fact, it amortizes itself over the course of 6 years.

Its totally feasible for a good majority of suburbia in the USA. It lowers our dependency on fossil fuels and is an absolute no brainer. Its not meant to eliminate the need, but reduce.

Ive already listed articles that show how beneficial these means are on the environment by peer reviewed scientific studies (not random google pages by guy saying trust me bro).

You just make some assumptions there that throw your argument out the window. Real world data shows its feasible and is helpful.

From eversource page, your payout is based on average rate of cost, not upcharged:

Am I paid for my excess generation at the same rate I am charged for consumption?

"No. Any excess kWhs at the time of the annual cash-out will be reimbursed based on the average hourly Connecticut ISO-New England Real-Time Locational Marginal Price (RT-LMP). For solar installations, the hours of 10 a.m. to 4 p.m. during the annual period are used to calculate the average. For all other renewable technologies, all hourly RT-LMPs during the annual period are included in the average. This is specified in the PURA-approved Rider N(PDF) of Eversource’s tariff."

Connecticut Net Metering | Eversource

Understanding and taking advantage of net metering options with Eversource in Connecticut.

www.eversource.com

Additionally, why the cost isnt going to my neighbors:
The RT-LMP is calculated by ISO-New England on an hourly basis. Eversource uses that information to determine the average price over the period specified. This RT-LMP is set by ISO-New England as the hourly clearing price of electricity, and takes into account the costs of generation, losses, and congestion. More information can be found on the ISO-New England website.

 

[lonetac]

If only there were some way to put a switch between the grid and the house if no input voltage is detected, like some form of switch...

If you have a battery, that actually gets you off the grid. Power can go off and you can still function normally.

Once you have solar you just need a battery and it can take you off the grid permanently.

 

[Endymio]

My neighbors bills are not impacted by my solar system. ,,, Eversource is a wracking millions of profit every year

When you force a utility to purchase electricity at a loss, you cost them money. When that utility has government contracts guaranteeing it a certain minimum profit, those losses translate eventually into higher rates for all other consumers. You're essentially using -- for free -- billions of dollars of utility infrastructure as a gigantic battery. The effect may be small today because only a tiny fraction of consumers do this, but that doesn't mean it doesn't exist.

Its totally feasible for a good majority of suburbia in the USA. It lowers our dependency on fossil fuels

Except the opposite is true -- as Germany found out. Forcing wind and solar on the nation actually increased their use of natural gas. And this won't change until we have a quantum revolution in energy storage technology.

Also note that Germany's solar-power expansion took it from the cheapest electricity rates in Western Europe to one of the most expensive ... five times what we pay here in the USA, sometimes higher.

 

[Che Cazzo]

That's an excellent ROI.

And one could tell the oil and coal companies' shills from some of those outraged individuals here... how their beloved fossil junk is getting less relevant by the day.

And the most hypocritical thing to read? Those same people who would kill any critter that moves...suddenly showing concern about birds allegedly because of wind mills!!

 

[gamerk2]

Except the opposite is true -- as Germany found out. Forcing wind and solar on the nation actually increased their use of natural gas. And this won't change until we have a quantum revolution in energy storage technology.

Also note that Germany's solar-power expansion took it from the cheapest electricity rates in Western Europe to one of the most expensive ... five times what we pay here in the USA, sometimes higher.

You apparently are *forgetting* how Germany shut down all its nuclear plants after Fukushima. Shot in the dark, but that might have resulted in the need for increased production from other sources.