SunPower AC w Microinverter or SunPower DC w SolarEdge

[jnook]

Hey guys,

New to posting but this board has already been is a great resource. I'm interested in getting a system installed soon, likely 45 SunPower X22 panels, after some debate I thought the efficiency was great and space is limited. I'm now debating between the AC panels with Microinverters and DC with SolarEdge inverter/optimizers. The installer is saying both are the same cost and he's giving me a reduction on the AC panel price, in fact there's also a SunPower rebate this month for an extra $1,033 and the Microinverters are warrantied for 25 years unlike the SolarEdge inverters which are 10 years (I read you can buy an extended SolarEdge warranty for $250 each inverter = $750). Ultimately the DC system seems like it will cost me about $1,750 more between inverter warranty and loss of rebate.

Unsure on how accurate the above details are... but my larger worry is the AC panels mean SunPower monitoring which doesn't have the panel level detail. The installer did say SunPower will have the consumption detail though, which the SolarEdge monitoring will not have. (I read you can install a SolarEdge consumption meter fairly inexpensive to get SolarEdge to show consumption also, need to investigate more)

So please let me know your thoughts and suggestions. Paying an extra $1,750 seems high to get panel level detail but I've heard SolarEdge monitoring is much better overall, and without panel level detail you don't really know if there are issues with a panel. I'd also always heard the AC panels were more costly so this is a strange situation.

[ButchDeal]

Hey guys,

New to posting but this board has already been is a great resource. I'm interested in getting a system installed soon, likely 45 SunPower X22 panels, after some debate I thought the efficiency was great and space is limited. I'm now debating between the AC panels with Microinverters and DC with SolarEdge inverter/optimizers. The installer is saying both are the same cost and he's giving me a reduction on the AC panel price, in fact there's also a SunPower rebate this month for an extra $1,033 and the Microinverters are warrantied for 25 years unlike the SolarEdge inverters which are 10 years (I read you can buy an extended SolarEdge warranty for $250 each inverter = $750). Ultimately the DC system seems like it will cost me about $1,750 more between inverter warranty and loss of rebate.

Unsure on how accurate the above details are... but my larger worry is the AC panels mean SunPower monitoring which doesn't have the panel level detail. The installer did say SunPower will have the consumption detail though, which the SolarEdge monitoring will not have. (I read you can install a SolarEdge consumption meter fairly inexpensive to get SolarEdge to show consumption also, need to investigate more)

So please let me know your thoughts and suggestions. Paying an extra $1,750 seems high to get panel level detail but I've heard SolarEdge monitoring is much better overall, and without panel level detail you don't really know if there are issues with a panel. I'd also always heard the AC panels were more costly so this is a strange situation.

SolarEdge Inverters come with a 12 year not 10 year warrantee and can be extended to 20 or 25 year.
SolarEdge can add a consumption meter as well.

[littleharbor]

I've heard about the Sunpower bumper to bumper warranty. Let me ask you this.... When the microinverters or optimizers start failing is Sunpower going to pay for labor to replace the failed parts? This will not be a one time event. Optimizers have less electronics to fail and have a pretty good track record. Personally I'd take the optimizers. Also do you have shading issues that warrant placing these electronics on the roof to begin with?

[jnook]

Thanks guys. Good to confirm on the consumption meter. And yes we'll have some partial shading during the day which led me to the micros or optimizers. The SunPower warranty does cover labor to replace the failed parts also... I guess in the end if the results will be fairly similar it comes down to the monitoring, is panel level monitoring worth paying extra for? Would love your guys thoughts on the monitoring for anyone who has experienced SunPower vs SolarEdge monitoring.

[fslipcam]

but my larger worry is the AC panels mean SunPower monitoring which doesn't have the panel level detail.

Sunpower has panel level monitoring for their AC panel https://www.solarpaneltalk.com/forum...020#post381020

[ButchDeal]

I guess in the end if the results will be fairly similar it comes down to the monitoring, is panel level monitoring worth paying extra for? Would love your guys thoughts on the monitoring for anyone who has experienced SunPower vs SolarEdge monitoring.

I have monitoring on both and the SolarEdge mondule level monitoring is much nicer and much better presented. Enphase doesn't give it out easily and even when they do it just is an awkward site to deal with.

Is it worth the difference? thats up to you.

I find it strange that the installer is charging more for SolarEdge on a 45 module array. Generally around 10 modules and solarEdge is cheaper for the equipment.

[bcroe]

Would love your guys thoughts on the monitoring

Some of us see no need for individual panel monitoring, all the complication it requires
lowers system reliability. Simple strings are about as reliable as it gets, and a fault
can be detected by comparing string currents (on your handy DC clamp on meter)
occasionally on a sunny day. I am still waiting for a panel issue after 3 million panel sun
hours. Bruce Roe

[adoublee]

Some of us see no need for individual panel monitoring, all the complication it requires
lowers system reliability. Simple strings are about as reliable as it gets, and a fault
can be detected by comparing string currents (on your handy DC clamp on meter)
occasionally on a sunny day. I am still waiting for a panel issue after 3 million panel sun
hours. Bruce Roe

Unfortunately strings are not a code compliant solution for new installations unless rapid shutdown electronics are installed on the roof. These have just as much complication and reliability concerns if not more. So we are left with what is the best that remains viable after a poor code provision. My opinion is that if the Enphase grid-independent operation promised for IQ8 turns out to be legitimate (and backward compatible to light up current IQ6/IQ7 micro-inverters), Enphase will move to the front in value proposition. If SolarEdge announces something similar, look for it to be available in 3+ years.

[JSchnee21]

I've not done a lot of digging on the supposed ability of the IQ8 to be grid independent. How would this work without storage? Having sufficiently large storage and enough dc to ac inverter capacity is what makes PowerWall's, Mercedes, LG and other grid tie storage options cost prohibitive (or at least not very cost effective) compared to generators. What will make the IQ8 so special?

Not trying to be negative. Just curious. IMHO, I always thought it was disappointing that StoreEdge didn't pan out. You've already bought the inverter, all you would need are some batteries.

Seriously though, a hybrid solution would really be best. It shouldn't have to be so hard to enable multiple battery charge options (PV and/or generator):

1) Storage with Inverter large enough to power entire house (or house minus Air conditioner)
2) Storage has two input chargers -- ideally both could work concurrently, but if not, then software to control.
3) Normally, Storage and PV on grid. Storage charges, offsets consumption, or is idle, PV offsets consumption and/or feeds back to grid
4) Power loss, storage feeds house. PV charges storage
5) PV output insufficient to keep up, battery drains to xx%, send signal to generator to start. Generator runs, charges storage, and or offsets consumption
6) Storage controller/interver connects to grid, supports rapid export shutdown in the event of grid loss as required. All other devices sit behind storage controller and have no need to interact with grid.

I understand there are hybrid, islanding inverters that do this today (at least I think that is what they are called). But this is an expensive, niche product, which (my opinion) seem to be designed in an FLA era, and hasn't kept pace with modern grid tied storage options from Tesla, LG, others.

IMHO, all modern grid tied storage solutions should support multiple concurrent charging options. This seems like a very minor optional upgrade to an already expensive appliance.

[JSchnee21]

Ok, as expected, storage -- while not technically required -- is needed to make the IQ8 system "useful." While I agree it is pretty slick that you can continue to run small loads automatically provided their power consumption is less than or equal to (or perhaps slightly over with voltage sag capability) your current PV output. Unless you live somewhere dry, sunny, and have no clouds/trees at all, your demand could easily outstrip production any time a cloud passes over causing the entire microgrid to collapse unless supplemental storage was also installed.

Interestingly, there appears to be little batteries or really large capacitors on the new IQ8 micro modules. I wonder how reliable they will be under real world conditions.

https://electrek.co/2017/11/09/solar-inverter-enphase-to-works-without-batteries-grid/

https://runonsun.com/~runons5/blogs/blog1.php/residential-solar/what-i-saw-at-enphase-mind-blown

https://pv-magazine-usa.com/2018/08/20/enphase-going-einstein-with-iq8-solar-power-inverters/

https://instylesolar.com/blog/enphase-iq8/

Where I think this could be really useful would be a small hunting cabin, boat, or similar where power is not needed most of the time (aka more of a luxury item). In this scenario, a small Microinverter system would be ideal assuming your consumption demands (lighting, charge your phone, etc.) were very modest and tolerant to an unpredictable power supply (clouds, weather, time of day). You'd save a lot of cost if batteries were not required and without the grid tie requirement, combining multiple micro outputs into a small load center would be a snap.

[ButchDeal]

I understand there are hybrid, islanding inverters that do this today (at least I think that is what they are called). But this is an expensive, niche product, which (my opinion) seem to be designed in an FLA era, and hasn't kept pace with modern grid tied storage options from Tesla, LG, others.

IMHO, all modern grid tied storage solutions should support multiple concurrent charging options. This seems like a very minor optional upgrade to an already expensive appliance.

Why do you think Tesla has a technologically superior solution to bimodal inverters.
It is just an AC coupled solution. You can do that with almost ANY bimodal inverter and any battery attached to it.

AC coupling has been around a lot longer than Tesla has had the powerwall 2 and lithium batteries have as well.

As for them only be a niche market in FL, there are bimodal inverter installs all over the US.

Also almost All bimodal systems support multiple concurrent charging, pretty much the default.

Some support generator boost which allows the inverter to help start loads that the generator is not capable of starting.

[adoublee]

I've not done a lot of digging on the supposed ability of the IQ8 to be grid independent. How would this work without storage? Having sufficiently large storage and enough dc to ac inverter capacity is what makes PowerWall's, Mercedes, LG and other grid tie storage options cost prohibitive (or at least not very cost effective) compared to generators. What will make the IQ8 so special?

I would highly suggest taking the time to read this.

Think of the SMA secure power supply that runs without batteries. However, it will supply full value of the PV production (or micro inverter ratings). It also will feed into normal house wiring - it is not a single outlet or circuit for a load that has to be plugged in the secure power supply. One the system becomes overloaded, it shuts down and then just comes back on when load has been reduced (or production increased). The only thing I don't know is how the devices know they are isolated from the grid - I hope that they can sense an impedance fingerprint and when you open the main breaker (or install an "automatic isolation switch") it just works. Batteries can be integrated to the scale of a better buffer for when clouds are rolling by (via one or more of their same IQ8 inverter) or more significantly for after dark operation. Supposedly some amount of wattage from IQ6/IQ7 series devices will ac-couple into some amount of IQ8 installed in the home microgrid.

This is all speculation of a future product getting UL listed and available for purchase, but it is encouraging to hear of this working demo.

[JSchnee21]

Thanks Butch, I'll have to look into these (bimodal inverters) in more detail.

Sorry, by "FLA" I meant flooded lead acid -- not the Sunshine state. I wasn't intending to suggest that Tesla was the bees knees from a technology perspective. But rather that grid connected, residential storage was a relatively new and fledgling product offering which was only just starting to come into its own. Companies like Tesla, LG, SolarEdge, Enphase, etc. with their brand recognition, all in one turnkey solutions, and modern, compact high energy density storage offerings are what is needed to drive the necessary consumer adoption to bring these technologies into wider acceptance and implementation. Additionally, my expectation is that a novel bimodal system from a company like any one of these would be an AC coupled solution which could co-exist with the homeowners existing PV investment be it Micro, Optimizer, or String.

My concern with a conventional bimodal solution is that these are all / mostly string inverters, correct? Typically with large, heavy, expensive battery banks for off grid / rural / or unreliable grid environments. To which you would then need to add rapid shutdown solutions as needed to meet the various NEC revision requirements. yes, it can be done. But you end up having to piece together a number of different partial solutions to make the whole.

For simplicity and cost effectiveness (and the high volume of units needed to make this a reality) you really want a simple all in one solution from a single vendor. I had hoped that StoreEdge would pan out. But SE seems to have dropped it like a hot potato. Perhaps Enphase will eat there lunch in this regard with there AC coupled solution.

At the end of the day, one can implement a wide array of natural gas, propane, and even gasoline whole house generator solutions for anywhere from $5K to $20K so until PV storage provides a similar offering, with extended run times, for the same or less money then one might as well just buy a generator -- and most folks that need them do.

[adoublee]

Where I think this could be really useful would be a small hunting cabin, boat, or similar where power is not needed most of the time (aka more of a luxury item).

I couldn't disagree more - especially if there is anywhere near cost parity with other optimized or micro-inverter grid-tie (only) systems. But to each their own.

[adoublee]

For simplicity and cost effectiveness (and the high volume of units needed to make this a reality) you really want a simple all in one solution from a single vendor. I had hoped that StoreEdge would pan out. But SE seems to have dropped it like a hot potato. Perhaps Enphase will eat there lunch in this regard with there AC coupled solution.

Just to be clear - what is being suggested for the Enphase function goes well beyond AC coupled. It becomes a GRID FORMING "voltage source" without requirement for a battery. Other things can AC couple to that if desired.

So Sunpower (or LG or any other panel) with separate Enphase microinverter is my vote for the original poster.