Swapping micro inverters - how hard?

[desmo907]

I am thinking of adding to my roof (flat) solar system (5.25kW). The vendor wants to add another 6 panels near my current 21 panels (3 rows of 7) but not append them as they will not look the same (my system if 6 years old). He will use another model panels that look similar.

He also recommended swapping out my (21) Enphase M215 micro inverters with a newer model (more efficient). So there is extra cost to remove my current panels and swap the inverters. I read and saw some videos and the swapping looks pretty simple. I think i can do it myself (if i can buy the micro inverters) but wanted advice on how to do it since I have 3 rows of 7 panels on my garage roof. The pitch is not bad but I assume I have to remove ALL the panels first to get at the inverters. Thus lower each to ground, etc. I am guessing i cannot walk on the panels to access those inner ones
I also wonder if it is worth the cost/effort to swap.... they have been running fine for 6 years now.
Thx!

[J.P.M.]

If something isn't broke, why fix it ? Do you change out your HVAC equipment because some peddler pushes something that's new but essentially identical to what you have ? More efficient my butthole. If you do generate any additional output by the swapout at all, it'll be minimal and besides, you'll never have any way of knowing how much, if any, performance improves. If the current micros have been OK for +6 years, I might buy a few as spares now against a future time when they won't be the same model or unavailable at all and you experience a failure, but that's insurance, not waste. I'd change out the micros when they fail, but not before.

Being a bit proactive is smart, but, IMO only, that bus left when you got micros in the first place. So be it. Opinions vary. Still, spending $$ and not getting anything like a reasonable improvement in reliability and/or performance with little to no financial gain that can't be measured anyway is not (smart).

I'm not a fan of micros, mostly because IMO, and for a lot of reasons, they're a bad idea, and as you note and are finally finding out, a PITA to get at if the usual poorly planned for access is considered.

To those considering micro equipped arrays or those systems with optimizers that will, at some point need access - and don't kid B.S. yourself - just like access to your shower/tub plumbing, some day it will be required: Take a lesson and think a bit when planning a layout. How will you get access to all the panels that will, one day, sooner or later, need it ?

Desmo: Do not walk ever on the panels any more than you'd walk on a flat, horizontal single pane window. First there's the safety issue. On top of that, panels are not meant to be walked on or carry a dead weight. Safety aside (but only for a moment), PV cells/panels can be damaged by the stress of the dead weight placed upon them and performance can suffer maybe to the point of panel electrical failure when the cells crack. A self inflicted pyrrhic victory. Not a smart move. You will also perhaps void any warranty by such abuse.

Whatever you do, if you were required to notify them/get their approval for the original installation, don't forget to tell the POCO and probably the AHJ what you're planning to do now, before you do it. For a lot of reasons, they'll want to know. Besides, not notifying them before hand if additional review/approval is required may get your tit in the ringer - and note: Yours, not some peddler's. If such notification is not required, a phone call or two is cheap insurance against the consequences of trying to skunk one by them if review/approval is required.

Take what you want of the above. Scrap the rest.

[ButchDeal]

If something isn't broke, why fix it ?

Most likely for compatibility with the new IQ line. It doesn't have to be done but then it would be two independent systems, or it could be done at it would be a single system.

Another option with similar labor costs would be to switch out to SolarEdge which could be beneficial if OP wanted EV charger or backup.

[J.P.M.]

Most likely for compatibility with the new IQ line. It doesn't have to be done but then it would be two independent systems, or it could be done at it would be a single system.

Another option with similar labor costs would be to switch out to SolarEdge which could be beneficial if OP wanted EV charger or backup.

If true, I've learned a couple of things. One about compatibility, and two, about the perhaps hidden costs of what looks like, to my ignorant way of seeing it, like avoidable built in obsolescence.

Butch: While you're providing what looks to me to be informed, and at least IMO anyway, usually helpful information, why not avoid even the appearance of peddling what you perceive as the benefits of your product at what looks, to me anyway, every possible opportunity, why not also inform those who may be in need of such helpful information of your perhaps ulterior motives as one who looks to have a fair amount of skin in the game as a vendor/supplier of SolarEdge equipment. Not for me to say - it ain't my game to run/not my venue, but it's pretty obvious, to me anyway, what you're doing, has been for a long time, and to me anyway, it's getting old. Take it for what it's worth.

Meant respectfully and straight,

J.P.M.

[ButchDeal]

If true, I've learned a couple of things. One about compatibility, and two, about the perhaps hidden costs of what looks like, to my ignorant way of seeing it, like avoidable built in obsolescence.

Butch: While you're providing what looks to me to be informed, and at least IMO anyway, usually helpful information, why not avoid even the appearance of peddling what you perceive as the benefits of your product at what looks, to me anyway, every possible opportunity, why not also inform those who may be in need of such helpful information of your perhaps ulterior motives as one who looks to have a fair amount of skin in the game as a vendor/supplier of SolarEdge equipment. Not for me to say - it ain't my game to run/not my venue, but it's pretty obvious, to me anyway, what you're doing, has been for a long time, and to me anyway, it's getting old. Take it for what it's worth.

Meant respectfully and straight,

J.P.M.

Absolutly. I do not sell solaredge and did not intend to imply that it needed to be swapped out, just that might be why the installer is suggesting it. It would give little benefit other than monitoring, to be clear and again does not have to be done at all.

[sdold]

Most likely for compatibility with the new IQ line. It doesn't have to be done but then it would be two independent systems, or it could be done at it would be a single system.

Another option with similar labor costs would be to switch out to SolarEdge which could be beneficial if OP wanted EV charger or backup.

Good points. I also don't like that he threw efficiency into the equation because the M215s are pretty efficient as it is.

Desmo, here's an opinion from a user, not a professional, so take it for what it's worth. Of the 46 M215s I and a couple of friends purchased 4-6 years ago, none have failed, so I have a good feeling about the reliability of the M215. One of those systems was an expansion on a house with an existing system using a string inverter, and there was no issue with the two different systems feeding the same service panel, so I don't see a compelling reason to replace the M215s unless you don't want to have two separate systems to monitor. That's a valid point, but if I was doing this I'd look into adding more panels with M215s, if still available with warranty, and throw in a couple of spares. The advantages would be not switching from (apparently) reliable units to less-proven units, and using the existing Envoy for monitoring. But even with a mix of new vs. old, I wouldn't mind, I almost never monitor my system anymore and it wouldn't bother me having two systems to look at instead of one to occasionally check the system.

[ButchDeal]

Good points. I also don't like that he threw efficiency into the equation because the M215s are pretty efficient as it is.

Desmo, here's an opinion from a user, not a professional, so take it for what it's worth. Of the 46 M215s I and a couple of friends purchased 4-6 years ago, none have failed, so I have a good feeling about the reliability of the M215. One of those systems was an expansion on a house with an existing system using a string inverter, and there was no issue with the two different systems feeding the same service panel, so I don't see a compelling reason to replace the M215s unless you don't want to have two separate systems to monitor. That's a valid point, but if I was doing this I'd look into adding more panels with M215s, if still available with warranty, and throw in a couple of spares. The advantages would be not switching from (apparently) reliable units to less-proven units, and using the existing Envoy for monitoring. But even with a mix of new vs. old, I wouldn't mind, I almost never monitor my system anymore and it wouldn't bother me having two systems to look at instead of one to occasionally check the system.

Actually a totaly different option would be to install m250 micros on the new modules which would allow expansion of the single array in monitoring and would deffinitly be cheaper. There might be some clipping on the new pv modules depending in the their capacity but that could be a minor issue. I would personally lean this way were this my customer. ( leave the M215s and add M250s)

[J.P.M.]

Absolutly. I do not sell solaredge and did not intend to imply that it needed to be swapped out, just that might be why the installer is suggesting it. It would give little benefit other than monitoring, to be clear and again does not have to be done at all.

So just what is your relationship with SolarEdge ? Any ? None ?

If you have no professional, employment, consultational, financial or any other type of relationship with SolarEdge, please accept my apologies for my assumptive error.

Seems like you pitch their paqrty line and mantra of goodies about as much or more than I pitch "Solar Power Your Home for Dummies".

[J.P.M.]

Actually a totaly different option would be to install m250 micros on the new modules which would allow expansion of the single array in monitoring and would deffinitly be cheaper. There might be some clipping on the new pv modules depending in the their capacity but that could be a minor issue. I would personally lean this way were this my customer. ( leave the M215s and add M250s)

Depending on shading, and cost, it might be worth considering the idea to scrap the micros all together and replace them with a string inverter that has multiple MPP tracking. Just sayin' that as long as a major inverter expense is being considered like changing out working micros anyway, it's a viable option that gets away from micros altogheter - again, as long as major shading is not involved. If the shading is that significant, it's a poor application anyway, so leave it like it is and don't throw good money after bad.

[ButchDeal]

So just what is your relationship with SolarEdge ? Any ? None ?

If you have no professional, employment, consultational, financial or any other type of relationship with SolarEdge, please accept my apologies for my assumptive error.

Seems like you pitch their paqrty line and mantra of goodies about as much or more than I pitch "Solar Power Your Home for Dummies".

I have no relationship to solaredge. In my opinion ghey have a superior product and we have installed a lot of them though not exclusivly.
Just like you and others prefer string inverters and i think you like fronius string inverters in particular.( could be wrong on brand).

I do have a small porton of my investing in solaredge ( less than 5% as i am very diverse).

[J.P.M.]

I have no relationship to solaredge. In my opinion ghey have a superior product and we have installed a lot of them though not exclusivly.
Just like you and others prefer string inverters and i think you like fronius string inverters in particular.( could be wrong on brand).

I do have a small porton of my investing in solaredge ( less than 5% as i am very diverse).

Before I respond to your main points, I do think that string inverters are a better choice for many, maybe even most, but not every residential PV application, at least in most of the U.S. But that's an engineering/ design choice, and not one suitable for every application, just like I think it's better in most residential applications to put the inverter in the garage or at least out of the elements as a preferred location, or that nat. gas fired heating systems are generally better than coal fired for most residential applications. Those are design considerations not brand preferences. I've got a rebadged Power One inverter in my garage that has additional and fit for purpose air cooling.

To your point about Fronius: Some of their design philosophy is better than some other of their design philosophy. Some engineers like SMA. There is no perfect piece of equipment. As a general equipment design philosophy, for me, and as a retired M.E., from an design and engineering standpoint, among a lot of criteria, simpler designs with thus fewer failure points are a better way to start and probably finish for me. So is common sense. Keeping the number of inverter heat and environmentally sensitive components as low as possible and keeping them out of harsh conditions (like on a roof) as much as possible, particularly where there will be little to no inspection/maintenance seems like common sense bordering on a no brainer. That's a lot of why I generally favor string inverters in principle. Micro inverters or optimizers do not fit what are to me, common sense requirements for most applications, and therefore, if I was designing residential PV systems, probably not making them my usual first choice. One exception being shade. But even there, if a location has shading to the point it needs micros or optimizers, I'd look long and hard as to whether that's a good application to begin with. Reason, and dirty little fact hiding in plain sight: Micros will not generate sunlight where none exists in the first place. The "I have shade so I'll get micros and solve the problem" is a common refrain that vendors do nothing to qualify. Micros, or optimizers will not restore insolation (BTW Butch - it's insolation, not insulation as you consistently seem to misuse/misspell) that's been lost to shade. If an application is, say, 30 % shaded, micros will not restore that lost 30 % - maybe half of that 30 % or so. So, you wind up with some recovery for what's a crappy application to begin with. Better than nothing, but my guess is less than potential users are left to imply on their own from the product literature. It's still a crappy application.

As for business relationships and how you define yours, it looks like we have different ideas of what a business relationship is. If you work for or own a company that installs and services SolarEdge equipment, and by your words, a lot of it, to me, that bears all the hallmarks of having a relationship with SolarEdge. Do you see where that could be interpreted by more than a few as having a business relationship with them ? If so, and acknowledging without question your undeniable right to opinions, by what looks to me at least to be your usual and strong defense of their systems and again, to me anyway, you often look like an apologist for what others see as failures and shortcomings of SolarEdge equipment and/or usually have an overly eager suggestion that SolarEdge has just the cure for a stated situation to the exclusion of just about everything else. To me at least and maybe I'm the only one, but you look to me to be one of their most persistent apologists.

Sometimes, probably often, perception, accurate or not, is everything.

Butch, this obviously isn't my forum to run, and not my call, but it is a place to exchange information and opinions. To me anyway, and maybe I'm the only one, it looks like you're using this forum to peddle a SolarEdge bill of goods.

As for investments, I once owned a boatload of Sunpower stock. I also own a Sunpower system that the stock appreciation paid for 10+ times over. You may have noticed that didn't ever and hasn't yet stopped me from calling B.S on their sales hype and preaching the "Sunpower is good stuff but not worth the premium" mantra.

The last word on this is yours.

Respectfully,

[ButchDeal]

As for business relationships and how you define yours, it looks like we have different ideas of what a business relationship is. If you work for or own a company that installs and services SolarEdge equipment, and by your words, a lot of it, to me, that bears all the hallmarks of having a relationship with SolarEdge. Do you see where that could be interpreted by more than a few as having a business relationship with them ? If so, and acknowledging without question your undeniable right to opinions, by what looks to me at least to be your usual and strong defense of their systems and again, to me anyway, you often look like an apologist for what others see as failures and shortcomings of SolarEdge equipment and/or usually have an overly eager suggestion that SolarEdge has just the cure for a stated situation to the exclusion of just about everything else. To me at least and maybe I'm the only one, but you look to me to be one of their most persistent apologists.

Sometimes, probably often, perception, accurate or not, is everything.

Butch, this obviously isn't my forum to run, and not my call, but it is a place to exchange information and opinions. To me anyway, and maybe I'm the only one, it looks like you're using this forum to peddle a SolarEdge bill of goods.

As for investments, I once owned a boatload of Sunpower stock. I also own a Sunpower system that the stock appreciation paid for 10+ times over. You may have noticed that didn't ever and hasn't yet stopped me from calling B.S on their sales hype and preaching the "Sunpower is good stuff but not worth the premium" mantra.

The last word on this is yours.

Respectfully,

remember though we do buyer brokering. and I (me personally) evaluate the technology and choose the best equipment to use. I do it based on technology and cost performance.
We install enphase as well and I personally view them as the best of the micros but sub to SolarEdge and some string systems like SMA.
We are NOT the installer, though we contract with them and give them the design that was work out with the customer.
I also use mac computers and have for many years, I am a unix guy and have been in the IT area for decades, so macs are a comfortable and technological fit. I also have done cost analysis on them and they tend to last longer and take much less IT time. Do I have a relationship with Apple because I use and recommend Mac computers? no I use and recommend them because in my opinion they are better for several reasons. By your logic (which is a bit circular) because I recommend and thus companies I have worked for have purchased a lot of Apple computers, I have a relationship with them. but that is now the case. The opinion drives the purchasing, not the other way around.

It is the same with SolarEdge, I feel it is superior and that monitoring is important particularly given our model of being a customer advocate that looks out (and monitors) the systems for the customer. We set up monitoring on other systems but it obviously is not up to snuff of SolarEdge monitoring.

and on Sunpower no I have not and I tend to agree with you on them. I only wanted to fully disclose that I have some, I actually worked for Lockheed Martin and about 1/3 (largest single section) of my investing is with them. It does well so I keep it. My solarEdge stock is the same way, when I deam it will not do well I will sell.

It really is my opinion that SolarEdge is a damn good system and on top of that easy and pretty safe for a DIY type install because of many of the safety features. I also prefer OutBack (and personally own one) for Bimodal systems, I know others like Schneider. My boss has one and I have had a lot of dealings with it, installed right about the same time as mine. His is crap and constantly having problems so my opinion of OutBack is likely to stick for a while. All of the bimodal and off grid installs we have done, except for the more recent StorEdge systems have been OutBack and my opinion has continued through with monitoring them.

We have done some Fronius installs and had poor luck with them. One install had two inverters and one was replaced twice, the other once. That was 3 or 4 years ago I think. We have primarily done SMA for string since that time but SolarEdge is the default inverter. We have done quite a few enphase, some for customers just wanted them and others because the system was too small or no good place to actually place an inverter.

I hope this helps clear up my opinion. I know I have stated several reasons on different threads of why have this opinion of SolarEdge, so no need to rehash that.

You and I just disagree on the general idea of simplicity of string in non shade situation over benefits of monitoring. I see your point and agree a string inverter has less points of failure and true a mildly technical person will see a failure. I am technical but years in IT has shown me that even technical people in one field are not the most adept at noticing tech problems in another field (computers or solar). I am not arguing that someone couldn't see it but that a lot of our customers and corollary a lot of general populous WOULDNT notice a problem. Hell riding in other peoples cars it is surprising how many don't knowtice basic problems with their own cars but this day and age there are so many people that have no idea how a car works much less what is a problem. My point is just that many people are pretty oblivious so a system that solaredge monitoring that can send alerts or have a third party checking is of benefit and in my opinion outways the benefit of reduced points of failure, also given the low failure rates we have seen. I also think it is good for people to see your opinion and mine and understand where we are both coming from so they hopefully can fit it into their own view for their install, on a tech board like this.

[J.P.M.]

remember though we do buyer brokering. and I (me personally) evaluate the technology and choose the best equipment to use. I do it based on technology and cost performance.
We install enphase as well and I personally view them as the best of the micros but sub to SolarEdge and some string systems like SMA.
We are NOT the installer, though we contract with them and give them the design that was work out with the customer.
I also use mac computers and have for many years, I am a unix guy and have been in the IT area for decades, so macs are a comfortable and technological fit. I also have done cost analysis on them and they tend to last longer and take much less IT time. Do I have a relationship with Apple because I use and recommend Mac computers? no I use and recommend them because in my opinion they are better for several reasons. By your logic (which is a bit circular) because I recommend and thus companies I have worked for have purchased a lot of Apple computers, I have a relationship with them. but that is now the case. The opinion drives the purchasing, not the other way around.

It is the same with SolarEdge, I feel it is superior and that monitoring is important particularly given our model of being a customer advocate that looks out (and monitors) the systems for the customer. We set up monitoring on other systems but it obviously is not up to snuff of SolarEdge monitoring.

and on Sunpower no I have not and I tend to agree with you on them. I only wanted to fully disclose that I have some, I actually worked for Lockheed Martin and about 1/3 (largest single section) of my investing is with them. It does well so I keep it. My solarEdge stock is the same way, when I deam it will not do well I will sell.

It really is my opinion that SolarEdge is a damn good system and on top of that easy and pretty safe for a DIY type install because of many of the safety features. I also prefer OutBack (and personally own one) for Bimodal systems, I know others like Schneider. My boss has one and I have had a lot of dealings with it, installed right about the same time as mine. His is crap and constantly having problems so my opinion of OutBack is likely to stick for a while. All of the bimodal and off grid installs we have done, except for the more recent StorEdge systems have been OutBack and my opinion has continued through with monitoring them.

We have done some Fronius installs and had poor luck with them. One install had two inverters and one was replaced twice, the other once. That was 3 or 4 years ago I think. We have primarily done SMA for string since that time but SolarEdge is the default inverter. We have done quite a few enphase, some for customers just wanted them and others because the system was too small or no good place to actually place an inverter.

I hope this helps clear up my opinion. I know I have stated several reasons on different threads of why have this opinion of SolarEdge, so no need to rehash that.

You and I just disagree on the general idea of simplicity of string in non shade situation over benefits of monitoring. I see your point and agree a string inverter has less points of failure and true a mildly technical person will see a failure. I am technical but years in IT has shown me that even technical people in one field are not the most adept at noticing tech problems in another field (computers or solar). I am not arguing that someone couldn't see it but that a lot of our customers and corollary a lot of general populous WOULDNT notice a problem. Hell riding in other peoples cars it is surprising how many don't knowtice basic problems with their own cars but this day and age there are so many people that have no idea how a car works much less what is a problem. My point is just that many people are pretty oblivious so a system that solaredge monitoring that can send alerts or have a third party checking is of benefit and in my opinion outways the benefit of reduced points of failure, also given the low failure rates we have seen. I also think it is good for people to see your opinion and mine and understand where we are both coming from so they hopefully can fit it into their own view for their install, on a tech board like this.

Thank you for what I believe is intelligent comment rather than the usual childish pap from snowflakes with misplaced, hurt feelings and childish, entitled attitudes that come out every time they read something that offends their delicate, overinflated egos.

I believe we agree to disagree on this one, but otherwise seem to be mostly on the same page.

With pre-apologies for breaking my last word commitment: My logic may appear to be circular only if the last sentence of your first paragraph is valid as it may relate to influencing a buyer's decisions. But I have a different view from the last sentence of your first paragraph: The customer drives the purchasing. The seller tries to shape the opinion of the buyer and so control which way the customer's opinion is driven, hopefully taking that opinion in such direction that it goes in the seller's favor using tools the potential buyer is completely and utterly unaware of. 10+ years in a prior existence as a peddler taught me that. My opinion only: What looks to me like your almost exclusive public endorsement of SolarEdge equipment still leaves me scratching my head. Maybe it's my attitude, and maybe I'm wrong, but after being on this planet for a long time, I've found if I think cynically, I've rarely been disappointed, with a bonus that when I've been wrong, I've been pleasantly surprised. I like to be pleasantly surprised but I can't see how that will happen this time.

On panel level monitoring : I do believe panel level monitoring can be useful to flag problems and can be a useful tool for system analysis. Truth to tell, I wish I had that capability but get by without it. But my guess is (and this is a comment on the result, not a criticism of any user choices), that's a system capability and information that may have more overall benefit to sellers for marketing hype than to most users who mostly neither know or care about system monitoring. Even if understood, my experience (and maybe/probably some educated guess) is that panel level monitoring is mostly a system feature ignored most of the time, or entirely. One upshot from that: The way I see and read about and suspect most users don't look at their array monitoring any more than they look (for example) at their water heater, and so, when a string inverter fails, probably/perhaps involving the entire system, that failure will probably produce a big result and that big result will get attention quicker and get a lot more notice than and perhaps a smaller panel failure which might go unnoticed more easily.

Now I am done.

[desmo907]

Good points. I also don't like that he threw efficiency into the equation because the M215s are pretty efficient as it is.

Desmo, here's an opinion from a user, not a professional, so take it for what it's worth. Of the 46 M215s I and a couple of friends purchased 4-6 years ago, none have failed, so I have a good feeling about the reliability of the M215. One of those systems was an expansion on a house with an existing system using a string inverter, and there was no issue with the two different systems feeding the same service panel, so I don't see a compelling reason to replace the M215s unless you don't want to have two separate systems to monitor. That's a valid point, but if I was doing this I'd look into adding more panels with M215s, if still available with warranty, and throw in a couple of spares. The advantages would be not switching from (apparently) reliable units to less-proven units, and using the existing Envoy for monitoring. But even with a mix of new vs. old, I wouldn't mind, I almost never monitor my system anymore and it wouldn't bother me having two systems to look at instead of one to occasionally check the system.

Thanks for the advice. I figured the 215 seems to be doing ok, so why change. Will talk to vendor to find out if I can stay with 215s with the extra 6 panels or 250s (if compatible). I assume you mean by a 'single array" is that they use the same net-meter and I only have to monitor (via network) 1 system. That would be convenient.

Seems the laws in CT have changed and net metering is going away.... but I am grandfathered in, and this may be a good time to add on since i barely make enough to cover my year usage anyway (we are frugal and a bigger family in the future who may use the a/c and dryer more will need a bigger system...

I am also on oil (water baseboard) heat and the solar guy recommended i look into a heat pump (my a/c is original from 1988). I need to run some numbers to determine if the costs and savings will balance out over time (how long?) - it would be nice to get off (or significantly reduce oil) as those prices also seem to rise.

[jflorey2]

Thanks for the advice. I figured the 215 seems to be doing ok, so why change.

In addition, 215 is 86% of 250; add inverter efficiency and you are at 90% of 250. It will be very rare to see your panels produce more than 90% of STC.