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DNAinaGoodWay
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Re: Microinvertors vs. Single invertors, what's the differen

Wed Oct 08, 2014 2:00 am

Warranty on string inverter is typically 10 years, and I was told I might have to replace it in 12-15 years @~$4000.

Warranty on micros is 25 years and Enphase monitors them, if one goes down they contact you and your install company to fix it, and pay you for lost production.
'12 SL last reading @ 2 yr, 22k, 260 GIDs, 62.35 Ahr

'15 SV w/QC, Mfd 5/14, Leased 8/14, 292 GIDs, 64.38 Ahr when new
@ 36 months, 34k, 270 GID, 57.49 Ahr

'17 Bolt LT



6.72 kW Array

Weatherman
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Location: Weston, Florida

Re: Microinvertors vs. Single invertors, what's the differen

Wed Oct 08, 2014 5:30 am

DNAinaGoodWay wrote:Warranty on micros is 25 years and Enphase monitors them, if one goes down they contact you and your install company to fix it, and pay you for lost production.


Sure... good luck there.

I've had eight out of my thirty micros fail in the past year and Enphase hasn't once contacted me or my installer. I always have to open a case with them, and, even then, they are slow to offer replacements. In addition to the eight, complete failures, there are six others which are defective (producing low power output during the day). Enphase refuses to replace those, because they aren't completely dead.

They, definitely, have never offered to compensate me for lost production.
2013 Crystal Red Volt
2012 SV Glacier Pearl LEAF; turned in 5/12/2015:18.6K Miles:50.13 AHr:10 bars, 24% gone

BrockWI
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Re: Microinvertors vs. Single invertors, what's the differen

Wed Oct 08, 2014 6:16 am

As Nekota noted another advantage or disadvantage of a single inverter system is the ability to supply power even if the grid goes down. It requires a battery setup and that is added cost, so if you main goal is just to recover the cost of installation then go with battery less single inverter since it will be the least expensive and fastest payback. If you want battery backup, think HUGE UPS powered by solar, then go with a battery setup, be aware that a battery system may never break even because of battery replacement, but it may pay for itself over time, and a genset will never do that :)
3 kw solar pv - XW6048 - 8 L16's
4 ton GSHP
2003 VW TDI 170k miles - 52 mpg lifetime
evse level 2 - Clipper Creek HSC-40
2013 S model with QC package Mar of 2013
@60k miles - 61.72Ahr - 94 SOH - 95.61 Hx - 268 GID

Smidge204
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Re: Microinvertors vs. Single invertors, what's the differen

Wed Oct 08, 2014 7:11 am

Re: battery backup;

AC coupling can be used to keep grid-tie inverters operating when the grid goes out, by using a battery-based inverter to provide the "clean" AC source that a grid-tie inverter is looking for in order to activate. You need a few extra gubbins to make sure the whole thing is properly isolated from the grid (e.g. blackout relay) and a way to control the PV system and/or a dump load in case you're producing more energy than you can use with the batteries fully charged.

This scheme should work regardless if you use traditional or microinverters.
=Smidge=

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DNAinaGoodWay
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Location: Central Massachusetts

Re: Microinvertors vs. Single invertors, what's the differen

Wed Oct 08, 2014 9:02 am

Weatherman wrote:
DNAinaGoodWay wrote:Warranty on micros is 25 years and Enphase monitors them, if one goes down they contact you and your install company to fix it, and pay you for lost production.


Sure... good luck there.

I've had eight out of my thirty micros fail in the past year and Enphase hasn't once contacted me or my installer. I always have to open a case with them, and, even then, they are slow to offer replacements. In addition to the eight, complete failures, there are six others which are defective (producing low power output during the day). Enphase refuses to replace those, because they aren't completely dead.

They, definitely, have never offered to compensate me for lost production.


Sorry to hear that. I don't know the details, but if I had that experience, I could bring it to the attorney general's office and get some resolution. Are you saying they have breeched your warranty? Or, do you have older micros, from when the warranty was less than today's? First negative I've heard of Enphase.

My two year old system has never lost a micro. I've had to shut off off some notification settings as it would notify me for trivial stuff like low voltage at sunset. My biggest problem is when Enlighten can't report because my cable is down (Charter Sucks!) but that doesn't affect production. I've gotton calls from my installer to check, when that happens, so I know the communication lines are working.

I hope you can get it resolved.
'12 SL last reading @ 2 yr, 22k, 260 GIDs, 62.35 Ahr

'15 SV w/QC, Mfd 5/14, Leased 8/14, 292 GIDs, 64.38 Ahr when new
@ 36 months, 34k, 270 GID, 57.49 Ahr

'17 Bolt LT



6.72 kW Array

Weatherman
Posts: 916
Joined: Tue Aug 30, 2011 12:03 pm
Delivery Date: 08 Jul 2012
Leaf Number: 20922
Location: Weston, Florida

Re: Microinvertors vs. Single invertors, what's the differen

Wed Oct 08, 2014 9:23 am

They have never failed to replace a completely dead micro. The fuzzy part of the warranty language is what they consider to be "defective". Here's the wording from the warranty:

"During the Warranty Period, Enphase will, at its option, repair or replace the Defective Product free of charge, provided that Enphase through inspection establishes the existence of a defect that is covered by the Limited Warranty. Enphase will, at its option, use new and/or reconditioned parts in repairing or replacing the Defective Product. Enphase reserves the right to use parts or products of original or improved design in the repair or replacement of Defective Product."

http://enphase.com/warranty/15-year-warranty/

There's nothing in the warranty, which defines what "defective" means. Obviously a micro which produces no power is defective, but one which cuts power back and runs about 8% less than its neighbors? Apparently Enphase doesn't consider that "defective".

There's nothing in the language of the warranty which says Enphase is obligated to compensate customers for lost production and nothing says they are obligated to monitor customer systems and take action on their own to correct "defects".


The m190 and d380 models have been shown to be very unreliable. I'm not the only one having problems with m190s. I fully expect a majority of my m190s will be replaced in the next five years and none will survive the entire 15-year warranty period.

I've read that the m215 and later models are more robust, so I wouldn't write off Enphase completely. It's just that a lot of us m190 owners got bad batches.
2013 Crystal Red Volt
2012 SV Glacier Pearl LEAF; turned in 5/12/2015:18.6K Miles:50.13 AHr:10 bars, 24% gone

kaikara
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Location: Ontario, Canada

Re: Microinvertors vs. Single invertors, what's the differen

Wed Oct 08, 2014 10:04 am

Just to add to the confusion there are also power optimizer systems like Solaredge provides. Basically a power optimizer is installed on each panel like with a micro inverter but you also have a main inverter like with string system. You get the benefit of being able to monitor each panel and it also deals with shading issues better then a single inverter system.

LKK
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Re: Microinvertors vs. Single invertors, what's the differen

Wed Oct 08, 2014 10:34 am

kaikara wrote:Just to add to the confusion there are also power optimizer systems like Solaredge provides. Basically a power optimizer is installed on each panel like with a micro inverter but you also have a main inverter like with string system. You get the benefit of being able to monitor each panel and it also deals with shading issues better then a single inverter system.


The SolarEdge system is basically a DC to DC converter attached to each panel. If a panel is shaded the DC to DC converter raises the panel's output voltage to match the rest of the string. By keeping the voltages consistent the shaded panel does not drag down the output of the rest of the array. The other advantage is the DC to DC converters allow the panels to kick-off earlier and stay on a bit longer. This is possible because the DC to DC converters are able to raise the output voltage so the string inverter can operate longer.

asimba2
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Location: Northern CA

Re: Microinvertors vs. Single invertors, what's the differen

Wed Oct 08, 2014 11:13 am

The Enphase M190s were unreliable, but they did pay the bill for my friend's installer to replace the failed inverters, they upgraded them to the better M215s, replaced ALL of them (not just the failed ones), paid for the lost power AND extended the warranty from the day of the new install.

I really want solar, but I generally use less than 500kW per month, which barely keeps me in Tier 1 at 11.8 cents per kW. Hard to justify the cost of solar with those numbers, but I hope for a solar breakthrough that increases efficiency and lowers cost to make it easier to justify.

Smidge204
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Joined: Wed Nov 24, 2010 1:42 pm

Re: Microinvertors vs. Single invertors, what's the differen

Wed Oct 08, 2014 2:23 pm

kaikara wrote:Just to add to the confusion there are also power optimizer systems like Solaredge provides. Basically a power optimizer is installed on each panel like with a micro inverter but you also have a main inverter like with string system. You get the benefit of being able to monitor each panel and it also deals with shading issues better then a single inverter system.

You also seem to get the worst of both worlds, IMHO.

Outside of service and initial cost, I don't see any advantage to having a single inverter. Having remote optimizers means you still have to pay for the single inverter but also each optimizer on top of that. You still have all the HVDC wiring so installation isn't simplified at all. You can't even retrofit the optimizers to an existing system as it needs the inverter with the "smarts" in it to work properly.
=Smidge=

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