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SolarCity Pushing Industry To 40% Increase In Useful Lifetime of Solar Power Installations (electrek.co)
An anonymous reader writes: SolarCity released a new report that says solar power systems have a usable lifetime of at least 35 years, which is 40% longer than what the market expects. Electrek reports: "The key finding of the report is that power degradation (annual efficiency loss) of solar panels supplied to SolarCity is as much as 35% lower than for a comparable industry-wide selection of non-SolarCity panels, which are typically expected to last for 25 years. In the study here, SolarCity looked at greater than 11,000 panels to determine their data points and come to their conclusion that their solar panels are performing well beyond expected industry standards. Today, standard efficiency solar panels put out by Tier 1 suppliers are generally warranted to lose no more than 0.7% efficiency per year for the first 25 years -- this is the Power Production Warranty. The key finding in this study is that the annual 0.7% efficiency loss is too high an estimation -- and that the number ought be closer to 0.5%. While it might seem a small number -- a difference of 0.2% -- when applied over a multiple decades timeframe, it means that instead of the standard twenty five year assumed productive life, we can expect at least another ten years of production above 80% of the original system output. Large installers like SolarCity, able to do this type of wide-scale research -- and to also demand higher quality, are showing their ability to pull the manufacturers of the world upward. With SolarCity building their own solar panel Gigafactory we ought expect the quality levels to be even greater in the near future.
Better not use Elon's terms unless you want to get Elon aquisition randy!
Solar city doesn't manufacture solar panels. Their factory is still being built and under multiple fraud investigations.
makes just as much sense. https://www.youtube.com/watch?...
That's what I saw on the boxes as Solarcity was unpacking them for my neighbors house. If they're anything like the rest of BenQ electronics... no thanks.
How about 40 years?
“He’s not deformed, he’s just drunk!”
when did self promoting 'reports' with unverified claims become newsworthy?
especially considering rather dodgy nature of company concerned, with all sort of litigations going on, rising borrowing costs( that necessitated a takeover from musk's other company), subsidy driven(=politician dependent crony capitalist) industry, etc , etc.
Isn't this just an advertisement by SolarCity? I think the entire posting should be downgraded.
"Unless something corrodes the electrical contacts, it will still keep working."
Probably not a bad idea for the factory to be a little modest with the specs to begin with.
The article does read more like a SolarCity ad than anything else. They certainly don't bring anything new to the table.
“He’s not deformed, he’s just drunk!”
I get a 404 error on the first link. The actual report link is at : http://www.solarcity.com/sites/default/files/reports/SolarCity%20Photovoltaic%20Modules%20with%2035%20year%20Useful%20Life.pdf
As for the degradation of panels, I have a 10kW system made of relatively inexpensive Chinese Renesola Virtus II hybrid panels for over 3 years now and I have seen no measurable degradation in performance so far. And I even look at the peak days of month to avoid the issue of daily weather and still it seems the peak has not reduced (rather increased by 1% which should be within the margin of error) in these three years. So there goes two myths my installer told me "you need to pay me to service and wash them every year to maintain peak output" and "output will measurably drop yearly anyway though". No I haven't washed them. So, I don't know if they will continue this trend or will suddenly drop in efficiency, but at least for the first few years they seem stable.
Violence is the last refuge of the incompetent. Polar Scope Align for iOS
It's even simpler than that. How can any company, that has only existed for 9 years, have any proof their product lasts 35 years let alone even 10?
By using math.
What's the expected lifetime and warranty of the inverter? The cost of inverters seem to be about $0.40 per watt so for a 3,000 watt system it would cost ~$1,200. There surely are It looks like they are warranted for 5 years but one would hope they would last longer than that. And I'm sure there are service contracts with guaranteed replacement. How many would be needed over 35 years? Hopefully not too many.
In a time of universal deceit, telling the truth is a revolutionary act. George Orwell
Good for Solar City.
They're still not putting their panels on my roof and charging me money for the electricity they generate. They can lease the space from me, but if they retain full ownership interest in the panels, I'm not giving them anything for free, much less paying them for the privilege.
How severe a hail storm can the panels survive? If the panels are well installed how much wind can they tolerate. In my part of Florida we will tend to have a hurricane every four years. 150 mph winds are common with gusts going even higher. Replacing a system every few years might make solar a really bad choice here. Also how much storm wind can windmills take without damage? It is hard to imagine one of the huge, tall windmills being smacked by the type of tornado so common in Oklahoma.
They should be more concerned with increasing the output of panels than increasing the lifespan.
The more efficient they are, the better ROCI we get. Then the lifespan and the inherrent % decrease in output does not matter so much.
I spoke to a power consultant last week and his opinon of the Tesla Powerwall was that it was rubbish and that there are better and cheaper solutions out there already.
Perhaps Elon has too many irons in too many fires and it is affecting his 'wizzadry'. Time for one of his projects to fail perhaps?
Lose the "what". It's redundant and makes you sound like a music-hall cockney.
At the bottom of the
I always think of the 80's anti-apartheid song where nobody cool wants to play there. I-I-I-I don't want to play SolarCity-ay-ay,
No, I don't actually use it. It is in my summer house in Greece and produces about 14MWh per year, which is sold to the electric company. ;) (from my eclipse report)
It is not optimally oriented, since it lies flat on a dual-pitched roof, with half the panels facing east and half facing west, but on some summer days I peak at 8.4kWh hourly, which is not bad at all.
And I'll throw in a graph I like, a partial (30%) solar eclipse as "seen" by my panels
Violence is the last refuge of the incompetent. Polar Scope Align for iOS
I'm curious how you replace your roof once you have panels on them. I'm guessing the short answer is "take them off" -- but does this including the mounting hardware, too, and how much of a hassle is this -- is a lot of the wiring modular and disconnectable, or is it hardwired for minimal losses?
If the panels last anything like the estimates, it seems likely that a roof replacement would be likely at least once during the PV system lifetime, perhaps more if the roof wasn't brand new. I'm guessing basic bell curve thinking is that anyone who installs them has a roof mostly too new to warrant replacement before installing PV panels.
Of course the ugly scenario sounds like it could be that not only will you pay to replace the roof, you'll pay to have the panels removed and pay to have the panels installed again. It might make sense to just have a new roof installed when you get panels owing to their life span since it may exceed your period of ownership of the house, but that's kind of another serious chunk of money for an already expensive proposition.
If the panels last anything like the estimates, it seems likely that a roof replacement would be likely at least once during the PV system lifetime, perhaps more if the roof wasn't brand new.
Depends on the type of roof. Metal roofs can last 30-50 years. It also depends on the particulars of the roof. Color, pitch, orientation, installation, material quality, local climate, etc. If I was having solar panels put on I would have the roof done at the same time if possible. You can get a roof that should outlast the panels but it won't be the cheapest option. Of course if you can afford solar panels today, chances are that the cost of a new roof probably isn't a huge deal to you. Plus the panels will probably extend the life of whatever roof they are over if properly designed and installed.
What probably needs to happen is to make it so the solar panels ARE the roof. Yes this has issues with angle of the sun and all that but the upside is that installation is a snap, replacement is easy and it looks better too. No need to worry about redoing your roof unless you are replacing a bunch of panels. On new construction you can orient the house to optimize sunlight capture.
They're still not putting their panels on my roof and charging me money for the electricity they generate. They can lease the space from me, but if they retain full ownership interest in the panels, I'm not giving them anything for free, much less paying them for the privilege.
You seem to completely misunderstand the deal SolarCity (and others like them) offer. It's basically a lease on a solar array. They install a solar array on your roof and sell the power generated to the power company. In return they sell you power at a discounted rate (fixed by contract) for the service life of the array. In essence they split the savings from the array with you. So you get all the benefits of a solar array without having to front the (substantial) cost of purchasing one and maintaining it. You're not giving them anything for free. You could buy and install the array yourself but you would be taking a much larger financial risk up front - for many people the cost of the array is prohibitive. But by leasing you give back some of the savings but don't have any up front costs or ongoing maintenance costs.
Leasing a solar array doesn't make sense for everyone but in the right circumstance it can be an excellent deal. You don't have to spend tens of thousands of dollars installing an array and dealing with the issues of maintaining it. You get a discounted rate on your electricity. Solarcity makes a profit selling the power. I've thought about doing this at my house someday.
So one witness in court claiming he saw the murderer is not proof but an anecdote?
Unless the testimony of that witness can be corroborated in some way then that is correct. By itself it is rarely sufficient because shockingly, people lie and are routinely wrong even when well intentioned. When it comes to science and engineering, eyewitness testimony is close to worthless and anecdotal evidence is generally considered dubious for good reason.
You americans are really quite dumb. Or your school system ... or what ever.
Really? You don't understand the difference between data and anecdotes and we are the dumb ones? Curious bit of logic you have there...
BTW: solar panels, as in photovoltaics, exist since over 50 years. We have a pretty good idea how long they last and degrade.
You do realize the panels we produced 20+ years ago are not identical to the panels we produce today, right? That's like claiming an 8086 chip from Intel should have the same failure modalities and rates as a modern Pentium chip. Your point is correct that we have a fairly good idea how they degrade but the reasons why are a lot more complicated than the fact that solar panels have been made for a long time.
Good call. I'm in Seattle, and after five years, my panels no longer put out enough power to even charge my batteries.
Then you have defective panels or possibly defective batteries. There is nothing specific to the climate in Seattle that would cause solar panels to degrade that fast.
I've spent more in Windex and paper towels than I've gotten back in power.
You don't clean solar panels with Windex and paper towels. If you are on the roof with Windex and paper towels then you are Doing It Wrong.
Solar might work in Arizona, but it certainly doesn't around here.
Strange. Solarcity could not make a penny if solar power didn't work in Washington and yet they do business there all the same... Thanks but I'm going to trust the profit motive of Elon Musk over they unsubstantiated ravings of an Anonymous Coward.
A roof is a lot more complex than "flat thing at the top of the house....
Well said. I think we're mostly talking about the outermost bit of the roof (shingles, etc) but you are quite right that a roof is a complicated structure which is much deeper than just the bit you can see from the outside. Far more complicated than many people realize.
I hope one day we figure out how to make it economically practical to turn the outer layer of the roof into solar panels or other useful things. Right now so many roofs are really just wasted space that could be put to better use much of the time. Solar panels, rooftop gardens, etc. Barriers to reclaiming that space are mostly economic at present. Commercial rooftops are particularly wasteful since they don't even have much aesthetic value. Places like grocery stores would (in principle) be ideal for solar arrays since their energy needs tend to correlate strongly with peak daylight. I figure once the payback gets to under 5 years or so we will probably see a tipping point. Right now payback tends to be 10-15 years which is just too long for many.
I intersected these various ideas and concluded we could preserve natural habitats by engineering the no-car type cities to maximize walkability and bicyclability, while providing a maximization of modern conveniences such as subway transit to a city edge garage, and minimizing the additional costs of maintaining such an urban center.
Excellent ideas but the real obstacle is supplanting existing infrastructure and finding some way to force it to happen on a wide scale as you seem to indicate. I'm not sure how you turn a city with a car based infrastructure like LA or Detroit into a pedestrian paradise as a practical matter no matter how sensible the plans.
It will at least make for good scifi; although eliminating both yard work
I'm a huge fan of anything that does away with grass yards. They aren't super attractive and maintaining them wastes VAST amounts of power and water and generates a huge amount of noise and pollution doing it. What's so bad about letting trees grow around your house for crying out loud? I've let much of my yard go to forest and the small bit that I do maintain (to exercise my dogs mostly) I now do with electric powered lawn tools. They finally have some excellent 40V lawn tools that work as well as gas powered ones while consuming less energy and being quieter. Two stroke engines are the devil's work...
More dodgy accounting from the Musk family. Extending the theoretical life of the installation increases the theoretical value of the asset.
In a less thoroughly corrupt system, the SEC would be chasing them for violating SarbOx. Musk though is a member of the protected class.
Did you hear? Pilip Morris has completed a decade long study that proves that cigarettes are good for your health. And, they verified that!
Can you believe that?!
Self-importance and self-indulgence is the root of ALL evil.