Enphase IQ8 ship date?

[AgileMike]

Very new to solar, but excited to do a DIY install on my home in Idaho. I sumitted my application to the utility company and it was approved.

I'm looking at a 9.2kW system using Enphase micro-inverters. I read about their new IQ8 inverters which will still produce power when the grid is down. I'm not familar with the company. Do any more experienced solar people have an estimate as to when these will be available to purchase? I have until December 2019 to install my system, but I'd rather do it this spring/summer and I'd like to use the IQ8s if possible.

Mike

[TJRoberts]

That's great! You are not alone! In fact, the Enphase loyalist army is now up to almost 1-million customers. Since 2013, my 20-Kilowatt, 87-microinverter-based solar system has made me money. I haven't had a problem with my solar system ever, and I installed it in 6 string segments from 2013-2016. Enphase is truly the symbol of reliability, safety and longevity, so you're making a wise choice. Here's your options...

you can install IQ7/7+ micros now, but you'll want to be able to match your IQ6/IQ7 in a 1:1 relationship with IQ8. So, if you install (2) strings of IQ7+ panels (2x13), then you would have to match that later on with 2 strings of IQ8 micros in order to form a complete microgrid. Also, realize that IQ7A is coming out soon which will have higher peak wattage capability up to ~450W. When Encharge storage becomes available later this year, the low-end 3.3kWh unit will have (4) IQ8's integrated, so having a few of them could also help you "complete" the microgrid allowing any IQ6/IQ7 strings to participate in a microgrid. With my 87 Enphase M-series micros, I will have to replace them, but that will be easy; I will pull the Enphase Trunk Cable, replace with Q-cabling, and IQ8 micros. I will also add an IQ Envoy on its own 20-Amp DP circuit, as well as a microATS.

Also, remember that in 2019, you get the 30% ITC, so if you install the bulk this year, you'll get the most tax credit.

One last potency is building out your entire system, and leaving some panels off, and wait to pair them with IQ8+. With IQ, you can mix IQ6, IQ7, IQ8 or IQ6+, IQ7+, IQ8+. In Europe, you can mix M-. S- and IQ-INT since all are based on L-N PLC communication. In USA, you have the division of M- and S-series and then IQ. IQ7PD, IQ7PD-215, IQ7PD-250 are all replacement IQ parts which work with the Enphase Trunk cable; they are L-N PLC communication models. The USA IQ6/7/8 will all be L-L PLC communication so you should be able to mix and match them, too. In this way, you would be able to take full 30% credit, then just add the micros to complete the microgrid. Ask your Enphase rep though. For a string of 13 micros, if 7 are IQ7+ and 6 are IQ8+, then would that extra IQ7 be incorporated into the microgrid??!! Either way, the flexibility microinverters provide is going to set the standard for MLPE in rooftop solar.

Good luck.

[Will792]

I cannot find IQ7PD units you mentioned. Are these available in the US?

I am asking because I am planning to extend my existing system with 21 215s to 80 with IQ microinverters. I can replace existing M215s and Enphase trunk cable with IQ but if I can keep some of the existing infrastructure it will reduce overall cost. I somewhat doubt that it is possible to sell M215 and Enphase trunk cable. Renvu is listing non IG M215 for $29 for several years and still cannot sell their inventory.

[tyab]

Welcome Agile.Please take the time to educate yourself about residential solar and the requirements you will be under in Idaho. For general education there are lots of resources on this site. Please have a chat with your AHJ at your county building department to make sure you understand their requirements for DYI and to follow their permitting process. You will be responsible for following all NEC requirements so be aware that there are many with numerous subtle aspects. Many of these requirements are not just government BS, they are there to ensure the safety of your home and family from shock and fire. You brought up possible future storage - be aware that in the vast majority of cases storage is negative ROI.

One of the reasons I stay around on this site is because the regulars and mods are no-hold's honest without any skin in your game - they will tell you what you don't want to hear and what no sales folks will tell you and if you read what they say and research you will be far more informed than before. Enphase has both positive and negative aspects so before you purchase anything (not just enphase) - research.

If you give us more information about your layout and electrical usage folk here will be able to give you much more relevant information.

[jflorey2]

VDo any more experienced solar people have an estimate as to when these will be available to purchase?

At SPI I was told "summer 2019" but those things have a way of slipping.

If it slips too far, there are other solutions that give you backup power (like the SMA secure power option.) Is there a specific reason you want microinverters, like a shading issue?

[JSchnee21]

Something I've always wondering for folks with Enphase systems that are adding on string after string. How do you avoid going over your 120% bus bar loading limitation with all of those additional load side taps (Enphase string circuits). Or are you using a combiner box and then tying into a line side tap? Or is this not rigorously inspected in the same way that a load side tap is inspected when installing a 7600W or larger SolarEdge inverter, for example?

Well, good luck on waiting for the IQ8. But I wouldn't hold my breath.

RenVu is saying Q3
(www).renvu.com/Learn/When-will-the-Enphase-IQ8-will-be-released

I'm not sure if the IQ7 shortage has been addressed yet or not
(www).renvu.com/Learn/Enphase-Shortage-2018-Why-What-To-Do?website=solar

While the Enphase IQ8 Micro-Islanding concept is very cool -- in practice, at least where I live (very cloudy), it would just be brownout city with lots of consumer electronics likely to get fried in the process from the resulting voltage transients. Without real battery storage to act as a buffer between production and demand the real time output of most PV arrays is much too variable to count on to run any real loads other than perhaps lighting. Not to mention needing to balance demand across the phases with an autotransformer.

(nowww)pv-magazine-usa.com/2018/08/20/enphase-going-einstein-with-iq8-solar-power-inverters/

As others have said, real storage is not yet cost effective, except perhaps, in some areas of California, Hawaii, and Australia. Natural gas or propane generators are usually more cost effective.

-Jonathan

[jflorey2]

Something I've always wondering for folks with Enphase systems that are adding on string after string. How do you avoid going over your 120% bus bar loading limitation with all of those additional load side taps (Enphase string circuits). Or are you using a combiner box and then tying into a line side tap? Or is this not rigorously inspected in the same way that a load side tap is inspected when installing a 7600W or larger SolarEdge inverter, for example?

I don't see that as much different than using a string inverter. I have two inverters on my system, for example, that feed a subpanel before feeding back into a single breaker on the main panel. What if I added a third string inverter in one of the spare spaces in the subpanel? Same problem.

While the Enphase IQ8 Micro-Islanding concept is very cool -- in practice, at least where I live (very cloudy), it would just be brownout city with lots of consumer electronics likely to get fried in the process from the resulting voltage transients. Without real battery storage to act as a buffer between production and demand the real time output of most PV arrays is much too variable to count on to run any real loads other than perhaps lighting.

Or phone/laptop charging, or fans.

For people who are going to rely on such a supply I recommend they get a cheap $99 UPS to buffer the unreliable power.

Not to mention needing to balance demand across the phases with an autotransformer.

I haven't seen any system out there that will run any 240V loads, so I don't think that's generally an issue.

[sdold]

Enphase is truly the symbol of reliability, safety and longevity, so you're making a wise choice..

I see by a brief Google search that you are in the solar business and are very much on a pro-Enphase mission. You're welcome to join in and contribute to the discussions, but don't use this forum as a platform to promote your business or Enphase, which in only one post you are already doing almost to the point of evangelizing. There are pros and cons to microinverters, they aren't for everyone, and we're not going to tolerate what a former moderator called "salesman's blather."

[JSchnee21]

I haven't seen any system out there that will run any 240V loads, so I don't think that's generally an issue.

So, the issue I was referring to is that Enphase Micro output is 240 VAC (aka 120V split phase). So let's say that each Micro can harvest 300W continuously under full sun, and maybe you have 24 panels for example (7.2kW). So that's 7200W / 240V = 30 AMPS. BUT that 30 amps is split half and half between the two phases. So that's 15 amps max per phase (aka per 120V circuit).

Now in your load center half of the breakers are on one leg (aka one phase) and half are on the other leg. Each Load/Line Side tap feed in (be it from Enphase, Solar Edge, Tesla, ABB, Fronius or other) is 240V for 99% of US residential installs so each leg only gets 1/2 the current. I suppose it is possible that the micro inverter circuity allows for some minor imbalance but I'm sure it's not more than 10% or so.

But here's the problem, the circuits in your house -- that is to say the ones you want to use during a blackout -- are spread willy nilly throughout the panel box. And even if their breakers were round-robin'ed. Your use of those loads is not even. No matter how careful and thoughtful you are. In the end, one leg will always be loaded more than the other. And this relationship changes dynamically as you turn stuff on and off (or it tries to do it for you -- remember all that stuff that was on when the lights went out?). And the amount of current you have available per leg changes throughout the day, weather, and time of year.

Normally, in the grid connected case, this small imbalance is inconsequential as extra current (produced or consumed) per phase just flows to/from the PoCo. BUT, in the storage or Micro islanding case (just like for the larger (100's of kW) UPS'es I have at work) it is the load of the highest leg that determines the total usable capacity. Just like for a generator. Though most storage/inversion solutions are a bit more tolerant to imbalance than a spinning dynamo.

Yes, you can move around the circuit breakers you most frequently use together to try and balance the load -- and this will help some -- the only true solution is an Autotransformer (installed between the loads and the storage/generation device) which will balance the uneven legs for you. Most serious off-grid and better grid connected storage solutions have them (Tesla, LG, Panasonic). Otherwise, worse case you're giving away 30-50% of the battery capacity you purchased. For generators, they are so cheap, comparatively, most people just usually oversize. Or for portable gasoline generators they wonder why the see high voltage on one leg while the other sags and the frequency is all screwed up.

Great, so let's say you're willing to accept only 15 amps per phase from your Enphase system. Great, have at it, just keep in mind that your loads and your insolation values vary second by second and this power source will only be available during the when you don't need lights (usually) and when most people are at work. It also doesn't work during heavy rain or snow storms or any other time when its cloudy.

Yes, it's nice for "free." But it's really nothing more than a propaganda tool. You'll still need to buy local UPS'es for all of your critical equipment. Yes, it may charge them to some extent during the day. But you'll still need flashlights and blankets.

Nowadays most appliances (microwave, fridge, increasingly hot water heaters, furnaces, ovens, washers, dryers, let alone TV's and computers) all have sophisticated and fairly delicate controller boards. They really dislike rapid and frequent power transients (brown outs, sags, abrupt losses, abrupt returns of power).

Good luck.

[Ampster]

.........
I haven't seen any system out there that will run any 240V loads,......

I am not sure I understand your comment My only experience is with Outback products and I know they will run 240v loads without the need for an auto transformer

[jflorey2]

I am not sure I understand your comment My only experience is with Outback products and I know they will run 240v loads without the need for an auto transformer

Off grid or hybrid inverters will indeed have no problem running 120 or 240V loads. I was referring to grid tie inverters (like SMA and now Enphase IQ8) that will provide some power during an outage without battery storage.

So, the issue I was referring to is that Enphase Micro output is 240 VAC (aka 120V split phase). So let's say that each Micro can harvest 300W continuously under full sun, and maybe you have 24 panels for example (7.2kW). So that's 7200W / 240V = 30 AMPS. BUT that 30 amps is split half and half between the two phases. So that's 15 amps max per phase (aka per 120V circuit).

Right. Per Enphase you will need something else, some device that separates the inverters from the grid, to allow generation of backup power. I very strongly suspect that device will provide you with 120 volts rather than 240, since there just aren't that many 240V loads that are useful connected to an unreliable direct-solar system.

How could they do that? I have no idea; there aren't too many details of the system available yet. They could provide half of the inverter's output on one side of the 240V line. They could switch modes and provide 120V (in phase) on both phases. They could switch modes and provide 60V out of phase on both sides. Or as you suspect they may incorporate a large autotransformer to transform the 240V to 120V (and balance the inverter's output at the same time.)

But as I said they haven't released too many details yet. They have said they want to support a "microgrid" which suggests their system may be more capable than the SMA system.

[ButchDeal]

I am not sure I understand your comment My only experience is with Outback products and I know they will run 240v loads without the need for an auto transformer

This is not quite correct. OutBack makes many inverters that are 120V only. I have one and to get 240V I have an auto-transformer. You can stack these 120V inverters or configure them to work together to make split phase 240V but even then it is HIGHLY suggested that you include an auto-transformer in off grid situations.
Outback has some new (Radian & skybox) inverters that will provide split phase 240/120V now but they include built in an auto-transformer in the systems.

[gbynum]

So, the issue I was referring to is that Enphase Micro output is 240 VAC (aka 120V split phase). So let's say that each Micro can harvest 300W continuously under full sun, and maybe you have 24 panels for example (7.2kW). So that's 7200W / 240V = 30 AMPS. BUT that 30 amps is split half and half between the two phases. So that's 15 amps max per phase (aka per 120V circuit).

Think that through ... 30 amps in the 240 volt pair of wires ... 30 amps through each breaker and bus. It will be almost perfectly balanced, so just mA through "neutral" or center tap conductor.

[JSchnee21]

Actually, gbynum you're right. Thank you for catching my math mistake. 7200W / 240V is 30 amps (2 pole). Which is actually 30 amps PER 120V phase -- not 15 Amps as I said before. I stand corrected. What I was trying to say is that it is NOT 60 Amps @ 120V (aka 60*120V=7200). But rather (X*120V) + (Y*120V) = 7200W. Where your ability to load X and Y depend on the location of your branch circuit's single pole circuit breakers in your panel board (e.g. odd or even)

While the PV production has the potential to be perfectly balanced when there is somewhere for all of that current to flow to (aka the Grid). In the Micro-Islanding / backup power situation, this is not necessarily the case. The Micros must dynamically scale their conversion from DC to AC such that production matches consumption in pseudo real time. The PV system cannot run at full production unless there is somewhere for the electrons to go. Given that your consumption will be unbalanced between the phases -- perhaps a lot, perhaps a little (unless you have all 240V loads). One leg will be able to take more or less current than the other. Unless you place an Autotransformer in between the 240V output from the Micros and the 2x 120V input of your load center.

The question is how smart the DC to AC inverter is, and how much spare design capacity it has in its circuity to tolerate this misbalance. It must have some headroom.unless as @jflorey2 indicated there is some additional device you need to buy (like an Autotransformer with a fairly large capacitor bank).

For example
(www).victronenergy.com/upload/documents/Datasheet-Autotransformer-32A-and-100A-EN.pdf
(www).outbackpower.com/products/integration-products/auto-transformer

Note that these have no Caps so very little ability to buffer variable production and consumption.

[Ampster]

This is not quite correct. OutBack makes many inverters that are 120V only. I have one and to get 240V I have an auto-transformer. You can stack these 120V inverters or configure them to work together to make split phase 240V but even then it is HIGHLY suggested that you include an auto-transformer in off grid situations.
Outback has some new (Radian & skybox) inverters that will provide split phase 240/120V now but they include built in an auto-transformer in the systems.

My recent experience is with Radian & Skybox so I should have clarified my comment. Your comment helped me remember back in 2015 when I was designing a my first back up/load shifting system. I had some circuits that ran with a common neutral so I used a Radian instead of some other workaround with the less expensive 120 volt AC inverters. It was overkill and I learned a good lesson, which I apparently forgot until now. LOL