Micro-inverter boom ahead? What do you think?

[Apxteck]

Hi

I come from the PV inverter industry, witness the whole development from very begining, and experienced many of the strories among the industry. Today, the micro-inverter become more and more popular, the successful cost control let it compete string ones. The features: high reliability, easier design & installation, more yield... seems it's the best option for the rooftop users, and will replace the string inverters in the coming years. What do you think? What's your opinion or experience? Just air your voice freely! It might be useful for the new system user or manufacturer.

thanks

 

[Marvo]

Welcome to the forum Apxteck. Please don't post any advertising or links.

 

[SolarCity]

The concept of optimisers and micro-inverters is fundamentally flawed.

Customers expect long guarantees from their installers - during which time, numerous units may fail. A disastrous scenario for installers.

 

[Apxteck]

The concept of optimisers and micro-inverters is fundamentally flawed.

Customers expect long guarantees from their installers - during which time, numerous units may fail. A disastrous scenario for installers.

Thanks for this.
To some extent, more point means more failure rate, but with average lower operating Volt., temperature, under the same manufacturing process, micro-inverter and optimizer will lasting longer. The right business(service) model will figure out the scenario.

 

[Ian-LS]

Enphase claim to have a failure rate of 0.2% so a 16 panel system less than 1 inverters will fail. So i guess about every third installation will have a inverter fail over the 20 year warranty it has

 

[Pascaleto]

Hi,
On theory it is very good. For very small applications I use them, from 6 months.
But I don't think that those Micro Inverters will work 25 years. And the cost for replacement will be very high. If we compared on cost per watt. More electrical connections - more trouble.
For roofs it will generate more heat to the panels - less generation.
For installations less than 1,5kWp I will use them, for bigger installation maybe not.
Thank you

 

[SolarCity]

On the vast majority of installations, the inverter is the item which is likely to fail. Changing a standard string inverter is relatively simple to do - and most manufacturers will actually pay the installer for his trouble.

So why don't the micro inverter/optimiser manufacturers back up their product with the same support?

I can see a lot of companies folding over time and some customers, or warranty companies, forking out a fair bit for essential maintenance.

 

[Matt_M]

Enphase cover cost of access for the first 5-years of their warranty

 

[SolarCity]

That's handy to know. Do you know of any other manufacturer that does the same?

For us, it is a deal-breaker.

 

[Pascaleto]

Did they give an amount of money (like 100 GBP), or have to represent invoice or something, to prove your expenses?
Because usually to replace a micro inverter is hard and take more time, then a string inverter. Because you have to go up on the roof and unmount a PV panel, and if this panel is in the middle of a row of PV panels is not very easy. And after that have to mounted it again.

 

[Matt_M]

Enphase have a service partner who they work with - basically if an inverter fails they will either send their service partner out to swap it (costing you nothing) or give the installer £150 to swap it.

We have installed circa 60 Enphase sites now and haven't had a single one fail. On the other side of that coin we have installed a dozen or so Enecsys sites which have been nothing but trouble. We've also put in circa 70 SolarEdge sites and only had 1 PowerBox fail.

The Enphase product is actually very good, you can tell it's a very well bolted together bit of kit.

 

[SolarCity]

£150? Why not the cost of the scaffold too? £150 would barely cover the labour costs on most installs.

 

[Matt_M]

I can only presume they are encouraging use of the service partner or assume that some kind of access system is used (roof anchor type thing)

 

[Worcester]

Maybe Easi-Dec

 

[Pascaleto]

Very nice!!!
They send somebody to do something after my work. To go on the roof and to remove panels and attach them again in the system.
Did they handle from this moment the guarantee on the construction works that my company is done - cabling, attachment of the panels, leakage in the roof and so on.
Who will take the responsibility if something happened after "Enphase" replacement team .
If they take it all - no problem even better. If not, it is a big problem for the original installer and even for the investor, if the both sides say that the problem is not on them.
What do you think?