Microinverter for LG315

[posol]

Hi,
I am decided to go with 11 x LG315 panels due to limited roof space. Now I have two options for inverters (I have some shading):
1) SolarEdge 3800
2) enpahse M250

I have a slight preference towards microinverter for three reasons:
a) my garage is crowded and central inverter and its related boxes will make it really ugly.
b) I am using a contractor to install the system so I think micro inverter installation will be easier for him
c) microinverter will be cheaper

First question: do above reasoning for micro inverter make sense?
Second question: which microinverter should I use for LG315? some are using M250 but the problem is that M250 is 250w whereas LG315 is 315w. so doesn't M250 clip the output of LG315?

Thanks a lot in advance,

[J.P.M.]

Hi,
I am decided to go with 11 x LG315 panels due to limited roof space. Now I have two options for inverters (I have some shading):
1) SolarEdge 3800
2) enpahse M250

I have a slight preference towards microinverter for three reasons:
a) my garage is crowded and central inverter and its related boxes will make it really ugly.
b) I am using a contractor to install the system so I think micro inverter installation will be easier for him
c) microinverter will be cheaper

First question: do above reasoning for micro inverter make sense?
Second question: which microinverter should I use for LG315? some are using M250 but the problem is that M250 is 250w whereas LG315 is 315w. so doesn't M250 clip the output of LG315?

Thanks a lot in advance,

Since you ask:

1.) IMO, not as much as possible, but opinions vary.

a) If your garage is already crowded, a central inverter may not make it that much more cluttered. Beauty is in the eye. Cleaning the garage is always an option.
b) Most folks do use contractors. I'd not do a contractor's thinking, especially and unless I know more about the contractor's job than the contractor does.
c) Usually, and if recent history is any indication, string inverter systems are less expensive than micro inverter systems.

2.) If your heart is set on micros, depending on location and orientation, you may get some clipping, but probably not a whole lot. Read the PVWatts help screens and review DC to AC size ratio. Try 1.26 (315/250) for that # and run PVWatts for an output estimate. Then, do another run w/ a 1.00 ration. Subtract the second run from the first for an est. of annual clipping. Like everything else, a SWAG.

[posol]

Since you ask:

1.) IMO, not as much as possible, but opinions vary.

a) If your garage is already crowded, a central inverter may not make it that much more cluttered. Beauty is in the eye. Cleaning the garage is always an option.
b) Most folks do use contractors. I'd not do a contractor's thinking, especially and unless I know more about the contractor's job than the contractor does.
c) Usually, and if recent history is any indication, string inverter systems are less expensive than micro inverter systems.

2.) If your heart is set on micros, depending on location and orientation, you may get some clipping, but probably not a whole lot. Read the PVWatts help screens and review DC to AC size ratio. Try 1.26 (315/250) for that # and run PVWatts for an output estimate. Then, do another run w/ a 1.00 ration. Subtract the second run from the first for an est. of annual clipping. Like everything else, a SWAG.

Thanks JPM for your help.
When you say "not as much as possible", could you explain that which part is not possible? I thought that SE3800 with optimizer can be used for LG315.

To me both optimizer and microinverters have the same problem; if they go bad you have to get on the rough and fix it. In fact optimizers are newer so they may not have been tested as those enphase microinverters. Any thought on this?

I also like the idea of microinvertor panels being easily replaceable and extendable

[J.P.M.]

Thanks JPM for your help.
When you say "not as much as possible", could you explain that which part is not possible? I thought that SE3800 with optimizer can be used for LG315.

To me both optimizer and microinverters have the same problem; if they go bad you have to get on the rough and fix it. In fact optimizers are newer so they may not have been tested as those enphase microinverters. Any thought on this?

I also like the idea of microinvertor panels being easily replaceable and extendable

You're welcome.
For the not as much as possible: that does not imply not impossible, just, IMO only, not the best way to go or very good reasons for going there.

For the rest of it, I do not think micros as good for most applications as string inverters. More failure points that are harder to get at placed in an environment less friendly to electronics than a garage or under cover. Micros usually add to system cost more than string inverters and the warranties, while longer, seem not to cover as much.

[cracovian]

I get clipped for a couple of hours in the full sun with my LG300s. M250s are rocking at 256 watts on a good southern exposure

[randomuser]

All the contractors who have proposed the LG315 for me used S280, not M250 micro-inverters. After going back and forth, over and over about Enphase vs SolarEdge, I'm leaning towards SolarEdge. An argument I've not heard much about is the cost of the Envoy gateway. It's a 2 year warranty and about $500 for it. I think that's the weak link in the Enphase solution. If that box lasts on average 8 year, I'm buying 3 of them. If it's 6 years, I'm buying 4 of them. People talk about the 25 year Enphase warranty vs the 12 year SolarEdge one. Is Enphase going to be around 25 years from now? Both companies are public and looking at the financials of both companies and comparing them, Enphase scares me. SolarEdge may also be gone before the warranty runs out. I'm looking at solar, thinking the electronic components won't last 25 years, so there will be maintenance costs assosciated with this.

[sensij]

S280's are new, they weren't an option when the thread was started. The scary thing about SolarEdge to me is that their system is proprietary... if for some reason they were to fall out of the market, an inverter replacement also means going up on the roof and pulling out all the optimizers. I have SolarEdge, and am willing to live with the risk, but at least with a standard microinverter, it can be exchanged for any other microinverter on the market at that time (trunk cable compatibility notwithstanding).