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fmfbrestel t1_j7lh1om wrote

Reply to comment by ga-co in US to add 29.1 GW of large-scale solar in 2023 by doboskombaya

Depends if you're okay letting your installation drop to 70% or possibly 60% of it's rated power. The panels don't just break after 25 years they just slowly lose power capacity.

I would hope that old solar farms just get new contracts with reduced terms, or new panels added to the existing set (space permitting) to top it back up to capacity.

That's something we'll have to look out for. If companies are throwing away 25-year-old solar panels, just because the power output dropped some, that's shitty and wasteful.

Profitable companies are sometimes shitty but rarely wasteful. So I have hope.

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[deleted] t1_j7llona wrote

[deleted]

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fmfbrestel t1_j7ltav3 wrote

The rate of decline has slowed down a lot. They might get cheaper but there's a fundamental limit to how efficient they can be, and we're already reasonably close.

Still. Free, because it's already there and producing power, albeit at a lower rate, will always beat not free.

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AssroniaRicardo t1_j7mqefv wrote

Most panels after 10 years are still outputting at 95%. Keep them clean.

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ga-co t1_j7lhchv wrote

I’ve always thought it was 1% per year loss of efficiency. I have a few panels on their third year and I feel like I’ve noticed a small drop off in performance.

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fmfbrestel t1_j7lt07c wrote

They tend to lose more in the first 5 years or so, and then the rate of decline flattens out somewhat.

But lots of variables are at play. The hotter the panels get the more they'll degrade, that's a big one. So panels in a field with good airflow around the mountings tend to stay cooler than panels mounted to rooftops with little to zero air flow behind them, and will degrade slower.

Manufacturers don't like losing money to warranty claims, so go take a look at almost any panel manufacturer and their power output guarantees. You'll see a quicker decline in the first few years then the rate of decline will shallow out a lot. And those guarantee figures are always going to be conservative in respect to what they actually expect to happen.

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