AC Modules

[SibertSolar]

Anyone worked with, or had a good look at AC output PV modules as yet?

 

[Donk]

Aren't the AC modules just standard DC modules with a built-in micro inverter?

 

[whinmoor]

I heard rumours Phonosolar we're teaming up with Enphase on this kind of technology.

Phono Solar partners with Enphase to launch new AC series of modules | Solar Power Portal

 

[Donk]

I visited Ecobuild last month and noticed a few panel manufacturers teaming up with EnPhase, most notably Solarworld. I had a brief search for AC modules but couldn't find anything. I personally think DC modules with the Enphase are a fantastic package. We've installed a few of these already and the customers are very happy with the way it works and they way they can monitor it.

A 4kw system we installed in Colchester, 30 degree pitch, SE (130) facing is consistently generating 21-23 kWh a day, this is in late March, early April!


Sorry for going off subject a bit there, got a bit excited!

 

[The Solar King]

LG launching products in Q3 in USA. Should come to Europe in 2015. As a major player moving quickly in terms of product development this should put cat among the pigeons.

There has been talk of panels with either optimisers or micro inverters, but nothing has materialised.

 

[Donk]

You know what I think?

Pretty soon we'll be saying "R.I.P, string inverters"

 

[jason121]

Enphase are good. They have there place but only when shade becomes an issue. Until Enphase drop there price a single string inverter is hard to beat. Problem with single string high voltage on roof.

 

[Donk]

When Enphase first pitched me their product, they made a few positive points I couldn't ignore, best point is that if in the first 5 years a unit goes down, they will fix it themselves. Production on a roof with no shading will out-perform most chinese string inverters, only the big boys (SMA, Aurora) seem to beat it (from personal experience).

 

[SpitfireW'sale]

I agree there are lots of good points to micro inverters but by "Only the big boys" would you presumably include the likes of SolarMax, Fronius or Stecca who all have high efficiency string inverters at a much lower price? Either way - the issue I have that persists is that you increase the maintenance liability. Fixing the inverter if there is an issue when it is on a roof could be very expensive. I understand they offer to fix it if it fails in the warranty period, but what if you make a mistake, or some other unforeseeable occurs where the manufacturer does not consider themselves liable? A repair to tighten a connector or something equally basic goes from fuel costs to hundreds of pounds or more. I would prefer to have all the technology possible installed somewhere easily accessible, leaving just the modules and framework on the roof.

 

[Donk]

but by "Only the big boys" would you presumably include the likes of SolarMax, Fronius or Stecca who all have high efficiency string inverters at a much lower price?

Yes definitely, the three you quoted (Swiss, Austrian and German) are all of an exceptional quality. We used to use Fronius on most of the PV systems we installed and they gave fantastic results with little to no faults, with the exception of the time/date resetting on a few.

If the roof is simple enough, it is possible to mount the inverters inside the loft, providing the dc cables are all brought into the roof correctly. Whilst this may seem counter productive, it does make maintenance easy. We used "Enecsys" in the past which unfortunately were unreliable so my teams began installing them in the roof space (where available) and it really helped.

If a fault comes in it has been identified as a loose connection/plug, I'll send the offending team back in their own time to fix it and they don't mind.

 

[jason121]

We are not a big company but have not a lot of faith with some of the inverter manufactures. We have had trouble will Fronius, Powerone and SMA. Each of them have asked me to repair there own inverters. They have never ever sent one of own engineers out to repair them. Steca are the only one who have done and that was to upgrade the firmware.

 

[Donk]

They generally will do that and I'm yet to see a penny for replacing THEIR faulty unit. We're installing an enphase system today as it goes, I always enjoy designing the system on the website and chatting with the customers about the monitoring system included. Time consuming but well worth it!

 

[Gavin A]

We are not a big company but have not a lot of faith with some of the inverter manufactures. We have had trouble will Fronius, Powerone and SMA. Each of them have asked me to repair there own inverters. They have never ever sent one of own engineers out to repair them. Steca are the only one who have done and that was to upgrade the firmware.

I've started including an amount for future warranty work in our pricing for installations, with the idea that we'll build up a pot of money to cover the costs of these sorts of call outs ourselves.

tbh I mostly prefer to do it ourselves as I don't like the idea of having random technicians doing work on our systems, and dealing with our customers - the situation with power-one updating the firmware for the remote display units was a complete farce, made a lot worse by their insistence on dealing direct with the customers and not keeping us in the loop. Personally I'd prefer to be trained as maintenance engineers for the key inverters we use, keep stocks of spares and do it that way, at least that would save time going to site twice if it were just a varistor or a fan needing replacing.

 

[SibertSolar]

Thanks for the replies guys, I was aware of the Phono and Canadian AC modules, was just curious as to whether anyone had any experience up close and personal. I will be discussing closely with Phono Solar in any case and will provide updates.

I have my own opinions on the pros/cons of micro technology and the challenges faced when integrating them into PV modules but I can't help feeling that the distant future will reveal this as being mainstream, IF certain aspects are carefully considered and resolved.

Ta