Failure rate of Micro-Inverters vs. Optimizers

sunnyboyo

Hello,

Calling all people with experience in optimizers, micro-inverters, or both.
Starting with all the environmental conditions being the same, which would you expect to fail first... a micro-inverter or an optimizer? Our customer wants panel-by-panel monitoring but neither I or my company has much experience with anything besides string inverters. Other factors like cost and production have already been discussed.

Any insight would be greatly appreciated.
Thank you

boB

Re: Failure rate of Micro-Inverters vs. Optimizers

Either one has a good opportunity to fail because they are mounted outside in fairly harsh hot-cold-hot-cold temperature cycling environment.

If there are more optimizers on the system than there would be micro-inverters, then statistically, I would expect an optimizer to fail first.

I do know a lot of the older Enphase micro-inverters have failed. Problem is that when one or the other does fail, it is harder
to replace because you have to go back up to the roof to troubleshoot the problem.

boB

BB.

Re: Failure rate of Micro-Inverters vs. Optimizers

My brother in law designed a component for one of the optimizers--He said there is not much in them. More or less the switching circuit, a micro processor, and a communications chip (he did the power switching circuit element).

I did not talk with him about reliability, but I don't think there are any "wet/filled" capacitors in them--So optimizers should be relatively rugged (if packaging is well designed and manufactured correctly).

-Bill

solarix

Re: Failure rate of Micro-Inverters vs. Optimizers

Converting from Solar DC to grid AC is a 2-stage process. 1st stage is a DC-DC converter that takes array DC and outputs a stable DC voltage for the 2nd stage which is the AC inverter converting the DC to 6ohz AC. Micro inverters do both stages up on the roof. Optimizers just do the 1st stage. The second stage runs at the low frequency of 60Hz and as such needs large filter caps usually of the electrolytic type which are especially prone to failure at rooftop conditions. Optimizers ought to be more reliable as a result.

sunnyboyo

Re: Failure rate of Micro-Inverters vs. Optimizers

Thank you all for your input. Logically it seems optimizers will fail less often, based on the fact they have less work to do and fewer parts.

Luigi chinè

Re: Failure rate of Micro-Inverters vs. Optimizers

[QUOTE=sunnyboyo;

Any insight would be greatly appreciated.
Thank you[/QUOTE]

It's difficult to say, see thw warranty that different manufucters give. Howevere if an optimizer fails this damages all the string, while if a microinverter fails, it will have an effect only on that panel, while the rest of the Pv plant continues to work properly

Luigi chinè

Re: Failure rate of Micro-Inverters vs. Optimizers

Failure rate doesn't depend on numer of component but how these components are stressed respect their rated parameters. Aurora Micro doesn't have electrolitic inside, this is just for your information