Which micro-inverters

[willingtolearn]

I am planing a 3kW PV system on a garage roof. Due to the structure of the building I need to place them at different angles and form Oct to February there are some partial shading issues. For this reason I would like to use either micro-inverters or optimizers. This is for an installation in Europe.

I like the idea of micro-inverters. This way I could use 4x600W and 2x300W for the the 10panels I would like to use. I would like to integrate the monitoring feature for micro-inverters so that additional cost needs to be considered too.

Now the question is which brand to use.

- ABB and APS are nice but too expensive
- enphase
- Northern Electric NEP
- WVC Kaideng WVC


What speaks against choosing the Kaideng WVC micro-inverters. Sure, the platform to monitor is not very well designed but is there another reason not to chose this low cost Chinese brand micro-inverter.

I've also been looking at planning the system with optimizers with SE, SMA inverters.

Purely from a cost persepective that meets the functionality I like WVC micro inverters.

What's the case AGAINST going with these?


thank you for your help.

[Mike90250]

Historically, micro-inverters have had high failure rates with roof top mounting and the thermal excursions (hot/cold/hot/cold/....).

Optimizers that locate more of the power electronics at ground level, in the shade, seem to fare better.

[willingtolearn]

I see your point about the changes in temperature that a micro inverter is exposed compared to a string inverter that is inside the house.

A micro-inverter can be placed like an optimizer and is therefore equally protected or exposed.

it would be interesting to see the failure rate of MI vs. String inverters.

[Mike90250]

One pioneer microinverter company is having a lot of early models failing. Optimizers are much lower power and fewer parts count and have lower failure rates, and their string inverter is at ground level and easier too work on.

[solarix]

Solar PV panels are super reliable and will last for decades. Do you really want to compromise that by putting electronics under them that will fail one by one sooner or later (probably sooner) requiring you or some poor soul to have to replace them one by one. Replace a string inverter once or replace micro-inverters one by one as they fail - your choice....

[willingtolearn]

Solar PV panels are super reliable and will last for decades. Do you really want to compromise that by putting electronics under them that will fail one by one sooner or later (probably sooner) requiring you or some poor soul to have to replace them one by one. Replace a string inverter once or replace micro-inverters one by one as they fail - your choice....

Thank you, I see your point and taking this into account it makes a huge difference where it is installed. Having this information now, I would certainly not want to have that type of setup on the roof of our house which is difficult to access. On the flat roof of the garage it would be an option IF the there were a cost advantage.

[Mike90250]

The only advantage I see to microinverters, is in a shaded area, where sunlight moves from one panel to another, and even then, I suspect the lighting is bad enough to not bother with solar at that location

[willingtolearn]

I have a complex garage roof structure and therefore need micro inverters or optimizers to help the yield from nov to March. Optimizers are another option so I will re-evaluate those (tigo /sma , solaredge) for another price comparison.

[Tdjj93]

Long Enphase! Their new IQ series are extremely something something something

Tdjj93 is banned till he tones this down a notch.