GRID INVERTERS , (GCI) Which do I buy?

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GRID INVERTERS , (GCI) Which do I buy?

Postby Tracker » Mon Dec 21, 2009 4:55 pm

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The average user has access to just one inverter - The one on their wall, and they all seem to do a job.

We know from other threads that total systems can deliver different outputs, despite their having been bought as a specific output.
Some have complained that their 2Kw design system, never attains that output, and only ever produces eg. 1.6Kw peak output.. ie. 20% Loss
Others declare that their system exceeds the design output, producing 2.2Kw. ie. 10% gain.

Yet others have complained - "I was to get ModelA, but was supplied ModelB, but I was told they are exactly the same?"

Many factors will determine which category a new system will fall under.

The number and variety of Grid Connect Inverters on the market, means that selection of an inverter is complex and confusing, and so when buying a complete installation, it is natural to just accept what is offered by the Installer..

These INVERTERS are all claimed to be the Latest design and the highest quality.

Elsewhere, the comment was made that Transformer-Less GCI's tended to be more efficient ( no transformer loss ) but were possibly not as robust as the transformered variety, which were noticeably noisier because of transformer hum.

So - the $64,000 question is - " What is the BEST inverter to be the proud owner of ? "

( here we are looking at typical 1Kw and 2Kw (output) systems )

Are there any installers out there who have tried various brands and models, and developed a strong preference for certain devices.
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In answering, you might assist by declaring the motive for recommendation.. eg. Reliability, Value (cost vs performance), Performance (ie. lowest LOSS)..
.
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Last edited by Tracker on Sat Jan 30, 2010 4:16 pm, edited 1 time in total.
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Re: The BEST Inverter (GCI)? Which do I buy?

Postby Joey » Wed Dec 23, 2009 3:01 am

Not sure if this will help your research Tracker , When I started looking around for my inverter I called a few companies and then an independent designer / Tech teacher , The later had no vested interest in any company but said if I didn't want to install high quality components he would not sign off on my system.
He told me though a bit over priced the SMA inverters are first class as far as efficiency , reliability and monitoring options.
One of the companies I called and asked to speak to a technician , he advised me that although they didn't stock SMA that he personally would not use anything else. , I also called Energy Matters and asked if price wasn't a deciding factor what is the best inverter? Again SMA and Second Fronius .

It was made painfully obvious through all my research that grid packages are built to a price and sold to people that are clueless , where the quality and components are quite often compromised to meet a competitive price range., unfortunately the inverter being a major system component this is usually the first thing that suffers the cut. , there can be $1000 difference between the correct model for the Job and one that will be screaming for air! , no guessing where that $1000 goes.
Being a clueless purchaser still should be no excuse for companies to rip people off with outrageous performance claims and inferior products.
I strongly believe whether you know a lot or nothing at all about this technology you should be sold and treated the same.
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Re: The BEST Inverter (GCI)? Which do I buy?

Postby zzsstt » Wed Dec 23, 2009 6:39 pm

Joey wrote:It was made painfully obvious through all my research that grid packages are built to a price and sold to people that are clueless , where the quality and components are quite often compromised to meet a competitive price range.


Sad to say that this statement covers just about anything that you might ever want to buy, in any market! The only thing that I would add is that PV systems (and just about everything else) are sold not only TO people who are clueless, but often BY people who are clueless! It is very rare to find a salesman who actually knows as much as they pretend, and the salesman who genuinely knows his subject AND is not swayed by the chance of making an additional buck is even rarer......

I always suggest you do all your own research and ask the salesman if he/she can see a problem with your proposal, or better still do your own research and propose a "bad" (preferably an over priced and under performing combination) system and see if the salesman picks up on it. If they don't point out the problem, walk away! Keep in mind that most solar salesmen will simply have downloaded the design tools from the inverter manufacturer and punched in the numbers. You can do that yourself!

Experience has taught me that you very rarely "pay for the name" as such, and far more frequently pay for the reputation that the name has gained. If the company can charge slightly more because they have a good reputation, it is very likely that the reputation is deserved.

With inverters, or anything else with a long anticipated life, a company with a reasonable history is likely to still be in business in a few years time (not always, but more often than not). A 50 year warranty from a new company that is likely to have vanished by next year is worth far less than a 5 year warranty from a solidly based enterprise. Also worth noting if they garauntee parts availability, that's worth a great deal after the warranty expires!

Having lived and worked around the world, I must admit to having a liking to German equipment. It tends to be designed and built at least on a par with aything else, more often it's better. As has been frequently pointed out, they also have a large installed base of PV systems so a manufacturer that is established in the German market can probably be "trusted".

On the basis of all the above, and my own research, my vote for a new system would probably go to SMA, unless there was a reason to g with another brand (like monitoring or intercommunication with an existing system). More specifically, probably one of their transformerless systems. The only exception to this would be if any specific requirements were present. For example, Fronius inverters seem able to deal with a wider range of string configurations, so have a much smaller granularity with regard to the number of panels which could be important if you were "growing" a system a couple of panels at a time. SMA inverters tend to have big jumps between the numbers of panels that can be utilised.
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Re: The BEST Inverter (GCI)? Which do I buy?

Postby rg767 » Sun Jan 03, 2010 12:21 pm

Tracker wrote:.
The average user has access to just one inverter - The one on their wall, and they all seem to do a job.

We know from other threads that total systems can deliver different outputs, despite their having been bought as a specific output.
Some have complained that their 2Kw design system, never attains that output, and only ever produces eg. 1.6Kw peak output.. ie. 20% Loss
Others declare that their system exceeds the design output, producing 2.2Kw. ie. 10% gain.

Yet others have complained - "I was to get ModelA, but was supplied ModelB, but I was told they are exactly the same?"

Many factors will determine which category a new system will fall under.

The number and variety of Grid Connect Inverters on the market, means that selection of an inverter is complex and confusing, and so when buying a complete installation, it is natural to just accept what is offered by the Installer..

These INVERTERS are all claimed to be the Latest design and the highest quality.

Elsewhere, the comment was made that Transformer-Less GCI's tended to be more efficient ( no transformer loss ) but were possibly not as robust as the transformered variety, which were noticeably noisier because of transformer hum.

So - the $64,000 question is - " What is the BEST inverter to be the proud owner of ? "

( here we are looking at typical 1Kw and 2Kw (output) systems )

Are there any installers out there who have tried various brands and models, and developed a strong preference for certain devices.
.
In answering, you might assist by declaring the motive for recommendation.. eg. Reliability, Value (cost vs performance), Performance (ie. lowest LOSS)..
.
.


Hi Tracker,

I have some distinct preferences based on efficiency, cost, and number of failures experienced.

Fronius in my view are highly overpriced and inefficient in the smaller sizes, but haven't used them much recently, nor have I seen any of the IG plus units used. I will be using about 10 plus models in January, so I will let you know. I have seen the tech specs and features on the plus series and they sound really interesting.

Latronics: interesting in that you can add batteries. I don't recommend them because they are painful to wire and they aren't terribly efficient/pretty/feature packed, but I will say that I have never seen a fault on one that wasn't cause by an electrician. Scratch that - I have seen one fault - a broken cooling fan. Easily fixed though. Bargain priced usually.

Same for SMA, but they are great in larger units say from the 3000TL/SB3800 size (the 1100 is abysmal with respect to efficiency and faults, and also getting it on to sub optimal sections of grid. The 1100 of course is being replaced with the 1200).

I would generally steer clear of the 1100, 1700 (one and the same) and probably even the 2500. I can honestly say I have never used a 3300, and I cant even remember if it is a down specced 3800 (3800s are pretty good btw). All the rest I would, and do use, but someone here mentioned string limitations, aside from the dual MPPT models this is usually always the case. Used everything up to 11000TL and 6000SMC and they are fairly solid, with the odd fault. Quickly replaced without question though when one does arise - I think that is SMAs great strength, they back their product to the hilt.

SMAs are usually pretty well priced.

The SEA Orion, whilst not outdoor rated, is fantastic value, and I haven't seen a single fault yet. The one thing that annoys me about this unit (aside from its indoor only status) is the lack of daily output data, it only does an aggregated total, but I love this inverter for its reliability and efficiency.If you have somewhere to put it, 5 stars. Fantastic price for the package.

By far though, if you have slightly more cash in the smaller range : for value, efficiency, aesthetics, and of course reliability I would look at the Power One Aurora, especially in the 3.6-6kW range. These things are great, and most of the larger units have dual MPPTs. Some of them even look beautiful! Fantastic price, especially above the 2.2kW units.

Transformerless units are definitely more efficient, but I cannot think of a reason that they would be less robust. They do throw up a new set of technical problems for everyone that I wont bother to go into, but unless you have Sunpower modules this probably wont matter to you at all.

I suspect that when the word robust is used, it sort of means solid, chunky and boring.
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Re: The BEST Inverter (GCI)? Which do I buy?

Postby Bthree » Mon Jan 04, 2010 12:20 pm

rg767 wrote:Latronics: interesting in that you can add batteries. I don't recommend them because they are painful to wire and they aren't terribly efficient/pretty/feature packed, but I will say that I have never seen a fault on one that wasn't cause by an electrician. Scratch that - I have seen one fault - a broken cooling fan. Easily fixed though. Bargain priced usually.

I suspect that when the word robust is used, it sort of means solid, chunky and boring.


A bit of info here, I have a Latronics PV-1200 grid connect inverter = robust but.

Just did a test on the actual efficiency of this unit.

986 watts DC input gave 915watts AC output averaged two readings 1 min apart = 92% efficient @12:10PM

Original spec from the book says Max efficiency 93% and the web site now says 94%

They are very boring and a little noisy but are cheap ... definately worth considering
Network = Powercor .. Retailer = Origin .. Installed Christmas 2008
Latronics PV-1200 feed by 8xTrina TSM DC-01 .. 170watt = 1360watts DC in .. 1096watts AC out .. 5+years later 990watts ac out
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Re: The BEST Inverter (GCI)? Which do I buy?

Postby Icarus » Sun Jan 10, 2010 4:50 pm

Hi rg767 ,
"I would generally steer clear of the 1100, 1700 (one and the same) and probably even the 2500. " Why would you aviod a SMA 2500 ? , thats what Iam being given in my 2kW system thou Iam think of asking for a transformerless one now any way .
Edit ; also I can get only 2kWs on my nth roof when later I want to put 2Kw on my west roof , should i just get a bigger Inverter now say a SB5000TL or will I be better getting another inverter ?

Cheers Dave
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Re: The BEST Inverter (GCI)? Which do I buy?

Postby rg767 » Sun Jan 10, 2010 6:17 pm

Hi Icarus,

I guess with the 2500 I suspect it is of similar vintage and technology of the 1100/1700. I will look for a technical review of the 2500 to confirm this either way.

I find 2500s usually quite expensive in comparison to other options also, usually they provide less features than much cheaper units.

If you are seriously looking at another couple of kW then a different inverter might be advantageous. It saves:

* Doing the entire AC side of things again;

* Saves getting a second grid connection approval;

* Aesthetically better (possibly);

* If you are on single phase it saves potential network issues.

The larger (4 and 5kW), twin MPPT inverters from SMA would be a great option, as would the Aurora versions of the same (3.6kW, 5kW and 6kW).

rg.
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Re: The BEST Inverter (GCI)? Which do I buy?

Postby Icarus » Sun Jan 10, 2010 9:38 pm

Hi rg ,

Do you mean the SB 5000TL ,is that a twine MMPT inverter is hard to find where it says it , even thou nearly twice the price you seem to get alot more for your money .

Ok I found an Aurora PowerOne PVI-5000-OUTD-AU sounds real good .

OK another edit is this it " Maximum of MPP trackers - 2 " and "strings Parallel 2X2 " ?

Thanx

Dave
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Re: The BEST Inverter (GCI)? Which do I buy?

Postby rg767 » Sun Jan 10, 2010 10:00 pm

Yes both the 4000TL and 5000TL have dual MPPTs.

2 by 15A inputs. They are certainly getting up there in price

The Auroras are cheaper by a fair way though. Both outdoor, both Dual MPPT again.
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Re: The BEST Inverter (GCI)? Which do I buy?

Postby Joey » Sun Jan 10, 2010 10:11 pm

rg767 wrote:Yes both the 4000TL and 5000TL have dual MPPTs.

2 by 15A inputs. They are certainly getting up there in price

The Auroras are cheaper by a fair way though. Both outdoor, both Dual MPPT again.


Don't know much about the Aurora inverters , are these transformerless ? do they have communication / logging options ? Bluetooth , how efficient are they ? also notice that EM don't sell them even though they do stock all the other well known high quality inverters., where are they made and how does pricing compare to SMA ?
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