Solar Clipping Explained
Вставка
- Опубліковано 12 кві 2021
- Solar clipping happens when solar electric (photovoltaic) panels provide more power than an inverter can handle. This means that DC power from the array is maxed out on a bright sunny day, there is energy lost because the inverter is not capable of converting all the DC power into AC power, but a properly sized solar system will always experience some clipping.
----- free solar quote -----
www.pacificsuntech.com/premium-solar-system
----- $500 referral program -----
www.pacificsuntech.com/referral
----- like, comment, and share ------
please be sure to like this video, share it with your friends, and subscribe to our youtube channel!
Between this and the startup voltage video, I can see how your design expertise gets max performance from a system. Props.
Clipping makes no sense at all unless the additional cost of a larger inverter will not be recovered during the life of the system by the additional revenue from the electricity produced during the clipped part of the curve, or if the clipping is required to stay within the power capability of the utility’s transformer and the larger array allows a longer operating time at the maximum (transformer limited) power output. Otherwise, clipping makes no sense at all. I find it hard to believe that the additional cost of a larger transformer would not be recovered during the 30 year life of the panels, unless the panels degrade so fast that clipping is no longer occurring after a few years of panel degradation. However, if the panels are degrading that fast, I suggest you have a bigger problem.
The best advantage is after a couple of years when your panels have degraded. With an oversized system you will extract max energy.
FINALLY!!! I've been hearing the term but haven't found an explanation until now. Thankyou I'm looking at REC Alpha Black 370 with IQ7+ The NMOT is 284 and the inverter rating is 290, so it looks good then.
Thank you. Now I understand. 👍
You showed a good example of what clipping is, but I don’t think you explained why/how a system with clipping produces “just as much” power. All else being equal, a curve that’s clipped off at the top MUST represent less power produced. So what else is different? Is the overall shape of the curve different? If so, why?
Yes, I was thinking the same thing. How 2 systems can produce the same if one is clipped? It doesn’t add up. Please explain. Thank you.
your probably not going to get an answer because it goes against the message. I think, what ever power is over the clipping line is lost power. That power is then burnet off as heat and not converted into usable power. Now, if one were to argue the the cost of more or bigger inverters wont make up what you would capture, could be true. All I have ever learned in electrical and electronics, is that clipping is bad for a number of reasons.
I believe the argument is that while not in clip mode, the panels generate more energy at any given time. IOW, the energy produced curve does change.
Also, as the system performance degrades, the clipping degrades, so the loss of energy productionover time isn't as steep.
Now, if you bought a better inverter, you could then also benefit from the previously clipped energy, but you are still left with the question of adding panels to clip the new inverter.
Either that is an infinite loop, or this video's analysis comes into play *at some point*.
You gain power with clipping because your curve will widen with more DC input. The system will produce more in the morning and afternoon when the sun is not at peak and reach peak inverter output sooner and last longer. Such a system will also produce more on a cloudy day when peak power is unattainable.
Hi, The results of my SolarEdge monitoring leaves me a bit confused. I just added 1260w of panels to existing 6500w on the roof (7760w total, 1.29 DC/AC ratio). I am using a SE 6000US inverter. When looking at my monitoring, I now notice clipping almost every day. I believe the clipping is occurring at a lower power level than it should. What max power should the named system show on the monitoring app?
Which enphase micro inverter do you recommend for the panasonic everbolt 370?
Interesting....
How powerful can a panel be for a IQ8A?
Local loss due to location is about 10-12% according to database and I am looking at XL panels 600 to 670w dir east/West setup - will an IQ8A handle that?
Do you have any formula for clipping loss calculation
So I got a 9.72 kW array, and a 6kW inverter. Does that sound right? Should I get one closer to 9.7 or will 6 work just fine?
The way I understand it is that you may clip at the top of the power curve, but because you have more panels, you are producing more in lower light, thus making more USABLE power overall.
So by getting REC 395 W panels with IQ7+ micro inverters isn’t too bad a decision? Cause I just got a 30 panel system installed but I’m feeling buyers remorse for not getting the IQ7A’s
@@gerryjimenez28 this should be fine when the panels say 395w that’s lab tested and at peak performance. I looked up your panels and in the real world performance it’s 293w. And the iq7+ has peak continuous power at 290w. That’s only 3w difference. And that’s if your panels is working at no degradation
@@CharlieeeS2 so my panels in real world scenario’s outputs 102 watts less then what it is Named? That’s ridiculous! 25 - 50 watts okay but 102, are you sure? Do other panel companies have this much offset?
@@gerryjimenez28 yes all panels are like this. If you look at the spread sheet of any panels, you’ll see 2 ratings. Lab tested and real world. In the lab tested they have large LED lights in a controlled room at around 70 degrees that are directly above the panels. Of course in the real world that’s not how the sun works. There’s angles and clouds and heat that effect the performance. Every 5 degrees above 70 effects the performance panels. The hotter the worst it is So you can imagine what you won’t be getting 395 watts. That’s why location is very important. If you live in Arizona for example , you’ll get sun blasting on the panels longer vs. in Massachusetts you’ll get less sun. Even if they are the exact system, Arizona will produce more khw. To off set that you’ll need more panels in Massachusetts to make up for the loss efficiency
@@CharlieeeS2 Thank you Charlie, I wrote negative reviews on the company that installed my system because their engineer said that my gain from using IQ7A over the pluses is inconsequential, so you agree? I probably owe them an apology….
How do you know youre inverters clips in stead of burning out? Are there external clippers? Like i want more power on ckoudy days. The 5 minutes per year the panels produce their max power i dobt care about 8 rather have somepower on a clousdy day without buying a huge inverter.
Thats the best review ive seen with regards to clipping. Could i ask a question please, im getting a quote in the uk for a 6.88kw array and have been offered either a 5.5kw or 7kw invertor for the same price. The panels are East facing for reference. Which size invertor do you feel will be better> Many thanks
One thing you’re not looking at is the cost. The system with the higher power panels would cost more but yet only produced the same energy as the cheaper system. So it can be argued that the system without clipping is “best value” as it gives you the most bang for the bucks.
Untrue, because a larger inverter is more expensive than utilizing a smaller inverter and adding more panels that have a far lower cost per unit.
Can you confirm if the solar edge hub inverter is able to use the clipped power to charge ev or charge battery?
Thank you for the video! Does this information apply to string inverters as well?
Yes it does! Though we tend to recommend up-to 150% oversizing as the max depending on region and orientation.
Thanks for the useful video on clipping. Which IQ8 inverter would best pair with the LG NeON R Prime 425W panel (15 panels, total DC system size 6.46 kW and total AC system output 5.93 kW)?
I would still use the IQ8A or IQ7A
@@dalerolph thanks! I was told IQ8H, but based on your clipping video, that seems like overkill.
One take away, I never heard the actual physical reason clipping was “Ok.”
because you're maximizing your annual production, not just your peak production month.
Except for the whole part of load clipping meaning extra equipment costs. Unless it's producing more in total, oversized DC systems are still a problem.
Is this "holding the power" still relevant with the IQ8 series? I'm getting clipping from 9am to 3pm and thinking I could have benefited from the IQ8M over the + that my installers used on my south-facing REC405 panels?
I feel the same. All the installers are giving me IQ8+ but I am asking for IQ8M or IQ8A.
@@RahulRathi_Multimedia If your panels face pretty much directly south and get full sun most of the day and are getting panels at least 400 watts (meaning you get over 300W real power from them), definitely insist on your installer going with the M or A. I wish I had. My panels have been active for a month now and it has been frustrating seeing all the wasted power of my 405's on these cool, sunny days. I literally have clipping the entire day, which results in a loss of about 2000 watt hours per day of full sun with my 21 panels (given the max of 309W for my panels). If your panels face east/west it's probably not an issue, but if they face south, yeah, ditch the IQ8PLUS and go for microinverters with higher sustained output.
The way it was explained to me, is that the inverter starts earlier and stops later, which is good because we tend to have more days with lower radiation than days with continuous sunshine through the day.
Yeah that's fundamentally the point of having a slightly smaller inverter to the module rating. We try to stay under 1.3 DC to AC ratio, and target 1.2 as the sweet spot.
@@dalerolphThank you for the video! Does this information apply to string inverters as well? TYIA
I live in South Texas and got solar. Its a 8.5 kilowatt system on a 6 kilowatt inverter. Pretty much its clipping every day there's sun. I feel im missing out on my system being able to produce more. Should my system be clipping everyday
It really depends on the inverter technology you have... is this a micro inverter system? Can you provide the solar panel and inverter model numbers? This would be located typically on the permitted plans...
I added more panels to charge my Bluetti acp200 . Used to be 2 200w panels added 2 more and now it seems to charge way way slower
Can someone explain what is wrong with maxing out on clipping?
Inverters PULL amps, like any tool plugged into the wall would do. So what is wrong with maximizing the size of your solar array?
As I understand it, the max voltage and amperage limits of the panels have to be within the safe working range of the in-circuit equipment (charge controller and/or inverter).
I have 25 Hyundai 395w panels paired with iq7+ micros. I live in Poland. On sunny day I get peak power of 7.4 kW but only for max 1,5-2h a day. Do you think based on your experience that I should go with IQ7A? Overall I'm very happy with Enphase.
You should look at the NOCT or PTC rating of the module not just the STC rating. If this other rating is less than the IQ7+ 295VA rating then you're good. If it's over you'll need to decide if it's worth the upgrade to IQ7A which is 366VA. The clipping you'll experience by be 5VA or even 10VA over is marginal, but if you're 40VA or 50VA over, then you probably want the IQ7A.
NMOT of the Hyundai HiA-S395H is 296. Since Poland isn't overly hot with avg summer temp of 17degrees, the panels output will be good assuming other factors are good, I'd prefer the IQ7A in this case. Since you say your "sun hours" are short, you want as much as possible during that time frame. Problem is, the IQ7A does not list compatability with 144 half cells, which is what your panel is www.solarelectricsupply.com/hyundai-green-energy-hia-s395hi-395w-solar-panel . You're limited to the the IQ7+ Personally speaking, if you only get an actual 1.5 - 2.0 sun hours a solar system might not provide an acceptable ROI. solargis.com/maps-and-gis-data/download/poland
@@datsuntoyy Hi, After almost 2months of production I can say that IQ7+ are good choice. Micros are peaking at around 300w but for short period of time during sunny days (1 - 1,5h max) So I think I would not get any benefit of getting IQ7A , which are more expensive. I'm overall very happy with that Enpase/Hyunadai combo.
NMOT of the Hyundai HiA-S395H is 296 - where did you got this info?
@@davidr922 it's in the link I previously shared www.solarelectricsupply.com/hyundai-green-energy-hia-s395hi-395w-solar-panel
Here is Massachusetts, my installer wants to make an LG NeonR prime 425 with iQ7+. His logic is that the panel won’t reach max potential here in MA with a room pointing SE. I think this panel is way to powerful for this inverter. What do you guys thing?
Every region is different and peak performance will play a factor. The IQ7Plus is rated for up-to a 440 watt module. You can check by using this tool: pvwatts.nrel.gov
How did it turn out?
@@shroud1390 Great actually. Clips for a hour and a half per day in the summer but make up for it with larger gains on the sides of the graph. No clipping in the fall and winter.
My installer told me that REC 400 panels they recommend lQ8M because no clipping. Now REC 405 are available and he also recommend IQ8M. What do l gain by getting REC405 instead of REC400 since the IQ8M AC power product are the same?? Also do you think IQ8M is good for REC405 panels??
You should still be good with the IQ8M, we wouldn't recommend going up to the IQ8A until you reach 420-watts
@@dalerolph Do l have advantages to get Rec 400 VS Rec 405 panels beside the cost??
So is this saying when you have clipping it produces at a higher rate for longer?.
Yes.
Can the clipped kW feed back into the grid? I received a quote for 17.16kw on a 10kw Sungrow Inverter and 16kw Battery. Trying to convince me that the excess will go back to the grid but I worry he's wrong.
No you can't go beyond 10kw to feed the grid. But I heard some inverters (solar edge hub inverter) can use the clipped energy to charge ev or charge solar edge battery whilst feeding the grid at 10kw ac
@@Weak_juan thank you replying. I will have to some more research. I'm ok with clipping, I just want to make sure the solar salesman is telling the truth. If not, then no sale for him.
except for a slight increase in cost, what is the downside of having no clipping? I keep hearing the phrase "a little clipping is a good thing" and except for cost, I see no reason to 'design for' clipping at all...
The system wont produce as much power as it could and will cost more. Clipping often helps increase overall production.
He forgot to mention the #1 reason why clipping is "OK" on a well design system... COST!!!
Is it possible to have 5.5Kw solar panels and a 3.68Kw inverter?
Yes, my system is 5.4Kw with 3.68 inverter, it works just fine.
Totally fine. Thats only a 1.44 DC:AC ratio.
I think some solar farms go up to 1.75x or 2!
A company in Houston, wants to install Rec alpha pure 395's with the IQ7+ is this OK? according to the salesman their engineer says that this is all the micro inverter I need I don't need to waste extra money with the IQ7A, Is this OK?
I have the Rec alpha pure 395's with the IQ7A. Im in NY. I didnt pay extra for IQ7A so I went to them. For me, 20 panels, IQ7A max AC is 7320w, and 5900w on IQ7+. For me, the cost wasn't a factor. On a sunny day in May, 13 Hrs of sunlight, of 4 hrs will be clipped with IQ7+. So far my Max is 7200, and i have the system turn on 7 days ago. I'm assuming with IQ7A, it will also clip, but less often. My panels are also south facing, no shade. So my math, 7200 -5900 = 1600*4hrs = 6.4kwh of lost production. Im not sure if clipping will happen during the summer. But so far I read clipping total hrs are around 100-200 hrs a year.
@@cloakingknight1 thanks for your reply, I went on ahead and let them stay with the Iq7+, I hope I don’t regret my decision, my system would of costed more though. I’m paying 40k but 10k is the Tax incentive so my cost is 30K, for 30 panels for a 11.8 KW system….
@@gerryjimenez28 yea, when factoring the cost, $20 each inverter is significant. Since us both have premium panels, clipping will occur offend. A guy monitored his system in Sydney and it clips 38% days in the year with his lg 370 panels. The money is more worth spent on another panel.
@@gerryjimenez28 courteous on pricing, how much a watt are you paying? Total cost and system size. Also does it include critter guards and CT clamps.
@@cloakingknight1 I calculated about $3.49, I told the salesman I would pay more for the IQ7A, he said Ok let me talk with the engineer, he contacted me 2 days later saying that the engineer said I would be better served with IQ7 or 8 +’s So not sure why so much clipping is ok?
If cost wasnt a factor, are you saying that you would rather have an Iq7+ on a 365w panel vs. the same panel with an IQ7A? How could you possibly generate more power with the 7+? What am I missing?
The 7A has a much larger voltage window as it’s intended for much higher wattage panels like the new LG 440. Spending the extra money for the 7A will equate to some more production over the 7+ but it’s like ~50kWh over the whole year. You need to look at the panels NOCT rating and that’s what you base the micros on.
So I am getting some LG 405 watt (STC) panels with an NOCT rating of 304 watts. I’m getting 57 panels. The installer offered the 7A’s over the 7+’s for a $20/panel up charge. This is not likely worth the cost, correct?
@@mmckinney525 i think you are right. Not worth it.
Simply, the two systems used for comparison do not have the same DC peak power. To clarity, please list the peak power of DC for each system.
If the microinverter companies like Enphase produced products that had output equal to or greater than panels on the market today, then there wouldn't be any clipping. Most people would prefer to have that top / clipped part of the bell curve.
When you properly pair the micro inverter to the solar panel the clipping you receive is less then 1%. Plus the modules degrades over time, and soil buildup occurs making the first couple years of clipping irrelevant.
37000 for the panels and still paying con ed 150 a month. Not worth it in nyc
As for the systems that “clip” wouldn’t you be better off going with a bigger capacity micro inverter to get the most out of your solar panel capability. This just doesn’t compute for me.
Inverters with a higher peak capacity cost more money. That money could also be invested in more/better/larger panels.
This video (tacitly) deals with the following optimization challenge:
"Assuming you have more than adequate (roof) space for solar panels (at attractive azimuth / incline / (lack of) shading), how can you harvest the most amount of energy per dollar invested in the system?"
In this case, it's better to save on inverter capacity and invest that saved money in more/better/larger panels according to this video.
The following different optimization challenge leads to a different answer:
"Assuming you have more than adequate financial budget, how can you harvest the most amount of energy per unit of (roof) space for the panels?"
In that case, it's better to invest in more expensive inverters that can handle the peak output of the panels under all circumstances. In that case you take for granted that the (more expensive) inverters have idle capacity not only in winter, but even the majority of the day in summer.
so you are telling me that it's OK to have clipping? that's like saying your car engine can produce 800hp but we're going to limit that with an ECU chip, now you only get 600hp. you should be designing a system that can produce the max peak that a microinverter/inverter/mppt can handle and just not let that excess power do nothing.
Depends on how much clipping and the type of technology being used. A micro inverter system with todays solar panel wattages are seeing more clipping then before, ideally you want to stay under 133% DC to AC ratio, so if the micro inverter had a rating of 200-watts AC then the solar panel should be less than 266-watts DC. But if you switch to a hybrid inverter design, you can go up to 150% or more because a hybrid inverter with a DC coupled battery will not clip but instead direct that excess solar energy into the battery. This is what the Powerwall 3 does as well as the SolarEdge Home Hub. So at peak times of the year, even though your hybrid inverter is rated at 7,600-watts AC and your solar is 11,400-watts DC that 3,800-watts of DC energy is not clipped instead it goes straight into the battery to recharge it.
How about a 6KW system with a 3.8KW inverter? Should the inverter be 7.6KW or due to clipping the 3.8KW inverter would be ok?
Ideally you'd want a 5kW inverter or a 6kW inverter, but you could do the 3.8kW inverter depending on the manufacture. SolarEdge allows for 200% DC oversizing, though that'd be a very significant amount of clipping (in our region). Where you're located is an important variable as well as the solar panels orientation.
This is smoke and mirrors with a solar salesman to give you a system that makes the most profit for the company.
“Hey this corvette has 600 HP (in the fine print, we only let you use 6 of the 8 cylinders so at peak you get 500hp)”
I do not think clipping is a good thing. I oversized my inverters to ensure clipping is not a factor. This leads to less stress on the inverter.
Would you run your car at full throttle 😂
@@kevinmlane4193 its the opposite. Inverters are more efficient when they are maxed. Its good design to have clipping because you are maxing the efficiency of the inverter. Its not like a car engine.
I am not sure I understand how clipping could be a good thing. I get that it max out the inverter output, but doesn't it waste the energy that the panel outputs that the inverter cannot convert to AC? If the panel output exceeds the output of the inverter, doesn't a higher rated inverter will unlock that extra bit of panel DC output?
You missing the point about micro inverter clipping. Watch this video ua-cam.com/video/oM8pbIg5sx4/v-deo.html
@@mrteausaable My understanding was correct. Clipping is just a compromise between lower energy production vs cost. When the inverter clips, you lose the potential energy output to trade for a lower cost of inverters. However, if the cost is the same, it is not something you want.
@@acefr8816 But the cost is not the same. A larger inverter will add significant cost. Adding a few lower cost per unit modules to maximize production in the morning and late afternoon is less expensive than upgrading the inverter.
@Brett Hartwig I agree there is a cost difference but whether it makes sense or not depends on the quote. The price difference of a larger inverter may not be significant between different companies.
Looks like you guys are not good at answering if people ask you something
We're very good at answering peoples questions
Your video is pretty much like telling the future out of looking at tea leaves. With the solaredge comparing, you don't give panel size, only that the left has 1 panel more. When I make a lot of guessing, I can make the conclusion: Buy an extra panel for $240 so you van spare $160 on an inverter to have 1% more production IN THEORIE............ In the micro comparising you avoid telling the WP of the panel. You only talk in the direction you want is to go. Such a shame..... And how do you explain that "in your eyes comparable installations" the 3,8kW inverter gets clipped, while the 5kW does not reach the 3,8kW with 5,4kWP input. Explanation: For the 5kW installation there is not enough sun. You must be lying that with clipping you get more power.!!! Start testing like a pro instead of pushing people in the direction you want.
Just because you are one of those pestering to subscribe even before I saw the video, I WILL NOT.
.... finding excuses for fanless overheating microinverter..last thing you want is inverter shutting down during peak hours..
CLipping doesn’t make sense . I cost you one panel. Micro inverters are cheaper now