Which micro inverter would be best for a 250 Watt solar panel?

[foo]

Solar Panel
Electrical Specifications
Optimum Operating Voltage (Vmp): 31.64V
Optimum Operating Current (Imp): 7.9 A
Open - Circuit Voltage (Voc): 37.78 V
Short- Circuit Current (Isc): 8.35 A
Maximum Power at STC: 250 W
Maximum Series Fuse Rating: 15A
No. of cells: 60 (6 x 10)

The Enphase M250 or the Enphase M215?
The Enphase 250 I see supports up to 300 watts but I can't find what the 215 supports up to. I do see that the closer to range you use the more efficient your system will be.
$50 difference in price.

Thanks in advance.

[Shockah]

The Enphase M250 or the Enphase M215?
The Enphase 250 I see supports up to 300 watts but I can't find what the 215 supports up to. I do see that the closer to range you use the more efficient your system will be.
$50 difference in price.

Thanks in advance.

Apparently you are attempting a DIY on-grid...

Easy answer:
Which ever device your POCO authorizes...
ask them which device YOU can wire into THEIR grid

[Ward L]

I have 250W panels and Enphase 215 microinverters. I think the microinverters clip the power from the panels a little, but the payout on the more expensive 250W microinverters isn't very good. Maybe there are cheaper 250W microinverters around that might be a better choice? It hurts to see your panel power being clipped by the inverter.

[russ]

Figure out how much clipping - in most cases it is a very nominal amount - a few minutes a fay at solar noon and when the ambient temperature is low.

[MGE]

I have 260 watt panels and use the m215's and I can't see any clipping. Looked at my monitoring today and saw 228w at peak at a few panels. 85% of 260 watts is only 221w so I feel lucky.

[OliverHevvy]

I have 250W panels and Enphase 215 microinverters. I think the microinverters clip the power from the panels a little, but the payout on the more expensive 250W microinverters isn't very good. Maybe there are cheaper 250W microinverters around that might be a better choice? It hurts to see your panel power being clipped by the inverter.

Not much. You might clip a little on June 22, but all the designs I've done show essentially no benefit to sizing the inverter for the absolute max power you might get someday from your panels if you're lucky.

JMHO.

[russ]

I have 250W panels and Enphase 215 microinverters. I think the microinverters clip the power from the panels a little, but the payout on the more expensive 250W microinverters isn't very good. Maybe there are cheaper 250W microinverters around that might be a better choice? It hurts to see your panel power being clipped by the inverter.

Your 250 watt panels may put out 250 for a few minutes at solar noon on a perfectly clear, cool and bright summer day. Normally they are less and well less.

[enersonmx]

Hi guys, I'm a little confused, hope you don't mind me asking here.

I'm quoting a 3. kW plant, I was going to go with a central inverter, but since the system is small, I'm considering micro inverters.

When I do quick calculations, I take the power of the system and multiply it by .8, and use that as the generating power.

My question is, since the enphase inverters give out an output of 215 W nominal, it's pretty much the same that a central system would, right?

I believe microinverters make a cleaner and simple installation.

What are your thoughts?

[J.P.M.]

Hi guys, I'm a little confused, hope you don't mind me asking here.

I'm quoting a 3. kW plant, I was going to go with a central inverter, but since the system is small, I'm considering micro inverters.

When I do quick calculations, I take the power of the system and multiply it by .8, and use that as the generating power.

My question is, since the enphase inverters give out an output of 215 W nominal, it's pretty much the same that a central system would, right?

I believe microinverters make a cleaner and simple installation.

What are your thoughts?

Try PVWatts and some reading prior threads.

[sdold]

Apparently you are attempting a DIY on-grid...

Easy answer:
Which ever device your POCO authorizes...
ask them which device YOU can wire into THEIR grid

They should allow either one, not sure why they would care as long as the rest of the system is designed for them...

I have 250 watt panels and M215 microinverters that I've just installed, and have been running for a week in the Sacramento Valley on average 90 degree days. They saturate only occasionally, not enough to bother me. I'm glad I went with the 215's.

Here's something that Enphase wrote up on the subject that might be helpful: http://enphase.com/global/files/Enph...ightsizing.pdf