Lifespan of solar panels

How long does a solar panel last? Someone’s spreading rumors on facebook that they only last for 3 years and then are toxic waste that needs to be disposed of.

Most panels have a 25 year warranty.

Solar panels tend to slowly degrade over time. Typically the rate of degradation is somewhere around 0.5 to 0.8 percent per year. After 3 years, a typical solar panel is still going to be operating at a bit over 97 percent of its original output. Whoever is saying they only last for 3 years is completely full of it. After about 25 years, the panels will typically be down around 80 percent or so of their original output. Plan on replacement after about 25 to 30 years.

I strongly suspect that someone who works in a field that competes with solar energy is behind the Facebook misinformation campaign, but proving that would probably be difficult.

Keep in mind that the original output is a varying % of the panels rating, depending on location and orientation. This is why more panels are needed to reach a certain level of power output over the 25-30 years they’re warranted for.

It’s been years since I worked for a PV company and got a couple of days of training, but as I recall, 80% after 25 years is high. I think the figures I was told were more around 50-60%, though panel technology has improved over the years.

Edit: Even at 50% of the original output, it’s not as if the panels are completely useless, they’re still providing “free” power.

I don’t recall the useful lifespan of the power inverters, but as I recall, the old large 'block" type inverters (the kind that’s attached the to wall of the home) would need to replaced before the 25-30 year warranty period is up. Not sure about microinverters as they came around after I left the company.

Somebody named Peabody, no doubt.

“Toxic waste” part is BS as well, solar cells are just silicon crystals. Even the solder is lead-free these days.

When the panels do fail, is it easy to swap them out for new ones?

Silicon is mined as quartz - creates dust, and causes **silicosis [\B] to miners especially when mining is done outside of US/EU.

Converting the quartz to metallurgical grade silicon requires big furnaces and high temperatures. The carbon footprint of this process is huge and there are associated emissions of Sulfur, etc.

Converting the metallurgical grade Silicon involves reacting it with Hydrochloro acid to make trichloro-Silanes. The trichloro-Silane is then reacted with hydrogen to make poly-silicon (that goes into the panel) and silicon-tetrachloride is produced as a byproduct. For every ton of silicon produced, 4 tons of Silicon -tetrachloride is produced. There is lot of toxic products produced in this which are recycled / used in US/EU per regulations but not so in other parts of the world.

Yes, there are toxic substances used in the manufacture of solar panels. Those toxic substances are all at the various factories, where it’s really easy to recycle them, and uneconomical not to do so (because the factories would have to pay to replenish their supplies of those substances if they didn’t recycle them). None of these toxic substances make it to the consumer, and when the panels do reach the end of their useful life, they can be safely disposed of in any way that you could dispose of glass.

And yes, the manufacture of solar panels is energy-intensive, and so it makes sense to ask how long it would take for a panel to pay back its own energy cost. But with current technology, that time is well less than the lifespan of the panel.

Yes, fairly easy.

All you have to do is replace the panels themselves (and probably the inverters – mostly they are integral these days). But the roof brackets, the wiring to the box, the meters & switching gear – all that is already installed, and doesn’t have to change. [On my house , all that took up most of the installation time. The actual panels went up in one short afternoon.]

I’m hoping (and guessing) that after even 15-20 years the solar panel technology is vastly better than whats on the market today.

According to Greenpeace and the Chinese Renewable Energy Industries Association, some two-thirds of the country’s solar-manufacturing firms are failing to meet national standards for environmental protection and energy consumption. The production of polysilicon and silicon wafers for solar panels creates dangerous by-products, in particular silicon tetrachloride and hydrofluoric acid, which are being discharged into the environment after inadequate waste treatment

cite : Tackle pollution from solar panels | Nature

Cadmium Telluride, Copper Indium Selenide, Cadmium Indium Gallium selenide etc are all chemicals used in different solar panels.

Agreed that the consumer of solar panels is not effected by these chemicals.

It has been shown that Cadmium and Tellurium will leach out into the groundwater if the solar panels are disposed off in landfills. Cite

Solar panel waste disposal is a major headache. EU requires manufacturers to build in the recycle cost affront. In California it is considered non-hazardous waste. In third world countries, they burn the panels to recover the copper, etc. and that creates another problem. Japan has its own problems with increasing (exponentially) solar panel waste.

That is only true for cadmium telluride thin-film solar panels. Only a few percent of solar panels are of that type (though I admit that I didn’t know they were even that common). Almost all residential rooftop solar panels are silicon.

World silicon dixide production is on the order of hundreds of *millions *of tons per year. The various metallurgical grades of refined silicon used for solar panels are on the order of hundreds of thousands of tons. It’s absurd to claim that demand from solar panels is anything more than the tiniest of blips.

These kinds of non-quantitative claims can often be traced to FUD from competing industries. “But X causes pollution too, so it’s just as bad as Y” is completely meaningless unless quantified. I see the same thing with anti-electric vehicle propaganda.

cite?

A 200 watt solar panel should produce something around 9000 kwh over 30 years. So unless it takes more than 9000 kwh to make one it should be fine.

Yeah but the panels themselves are getting to be pretty cheap. Right now its only about $0.50 per watt of solar panels, down from $5-10 per watt in the aughts.

The panels themselves are no longer the cost bottleneck, the cost bottleneck are the soft costs like installation, wiring, profits, regulations, etc. A home solar system may cost $3 per installed watt, but only 1/6 of that is the cost of the panels.

One idea that may catch on is an all in one solar and battery setup that can be installed in your yard. Of course right now that is pretty expensive, around $5/watt installed I believe.

California has mandated that new homes have solar, so their solar production is climbing rapidly.

As Wesley Clark said, panel prices are around $0.50/watt today. Even if the entire cost of that panel was from energy, and even if that energy came from the dirtiest, nastiest coal power there is, one watt of panel would still take at most 25 kW-h to produce. But the panel is likely to produce 2 kW-h per year for 20+ years.

This is wildly pessimistic, of course. Only a small fraction of the panel cost is in energy, so really the panel is paying its energy cost many times over.