Hi guys

I recently signed up for a deal with one of our big name installer/contract solar companies.

They advertise a 6,5Kw system, with 10Kw batteries, and 12 panels.

I managed to get a good look at the system before their custom closed box was fitted over it, and I noticed that it contains a Goodwe GW5048D-ES and four Pylontech Us2000c batteries. 

I'm not very clued up on these things, but I looked it up and this Goodwe inverter offers 4,6 Kw backup, while the four batteries only offer 9,6Kw of storage. 

Am I being pedantic and is there some magic calculation I am missing, or am I being ripped off?

When I queried it with the installer, they claimed that the inverter's rating is due to it offering a mix of AC and DC, and there is a calculation which brings it to the advertised 6,4 Kw, despite the below specs:

• Model	GW5048D-ES
  Battery Input
  Battery Type	Li-ion or Lead-acid
  Nominal Battery Voltage	48V
  Max. Charging Voltage
  Max. Charging Current	100A
  Max. Discharging Current	100A
  Battery Capacity	50 to 2000Ah
  PV String Input
  Max. DC Input Power	4600W
  Max. DC Input Voltage	580V
  MPPT Range	125 to 550V
  Start-Up Voltage	150V
  Nominal DC Input Voltage	360V
  Max.Input Current	11/11A
  Max. Short Current	13.8/13.8A
  No.of MPP Trackers	2
  No.of Strings Per MPP Tracker	1
  AC Output (On Grid)
  Nominal Apparent Power Output to Utility Grid	4600VA
  Max.Apparent Power Output to Utility Grid	5100VA
  Max.Apparent Power from Utility Grid	9200VA
  Nominal Output Voltage	230V
  Nominal Output Frequency	50/60Hz
  Max.AC Current Output to Utility Grid	40A
  Output Power Factor	1
  Output THDi	<3%
  AC Output Data (Back-up)
  Max.Output Apparent Power	4600VA
  Peak Output Apparent Power	6900,10sec
  Max.Output Current	20A
  Nominal Output Voltage	230V (+/-2%)
  Nominal Output Frequency	50/60 (+/-0.2%)
  Output THDv	<3%
  Efficiency
  Max/Efficiency	97.6%
  Max.Battery to Load Efficiency	94.0%
  European Efficiency	97.0%
  Protection
  Anti-Islanding Protection	Integrated
  PV String Input Reverse Polarity Protection	Integrated
  Insulation Resistor Detection	Integrated
  Residual Current Monitoring Unit	Integrated
  Output Overcurrent Protection	Integrated
  Output Short Protection	Integrated
  Output Over Current Voltage Protection	Integrated
  General Data
  Operating Temperature Range	-25 to 60 degrees Celsius
  Relative Humidity	0 to 95%
  Operating Altitude	<4000m
  Cooling	Natural Convection
  Weight	30kg

7 hours ago, justchecking123 said:

 they claimed that the inverter's rating is due to it offering a mix of AC and DC, and there is a calculation which brings it to the advertised 6,4 Kw.

What a bunch of hogwash! 

You're right its a 4.6kW inverter...it may handle 6.4 with AC passthrough, but DC to AC is 4.6kW

A 6,5kW Inverter will be able to supply 6,5kW either from Solar or batteries. This inverter can only only supply 4600W. Whatever the AC throughput is from grid is not part of the Inverters own generation/conversion. 
The max PV input is also limited to 4600W, so what 12 panels are they including in this deal? 380W perhaps?
this all sounds very devious marketing and slick sales talk to bamboozle the uninformed.
Did they give you the spec sheet that you posted?

I just checked the Goodwe datasheet and the model you specced is 4600W as well but the solar DC input is actually 6500W.
So your data sheet seems to be a mix of the two.

Still, this inverter is not a 6,5kW. The only thing that is 6,5kW is the max solar input

Edited October 19, 20232 yr by zsde

Thanks, guys.

 

This is what I suspected.

I assume this is how they trick people, since they usually do the installation and then stick the whole thing into a box that prevents you from seeing what equipment is actually in there.

 

I'm now torn between demanding they bring me what I paid for, or cancelling the entire deal, since I don't want to deal with untrustworthy companies.

 

The worst part is that this is supposedly one of the top rated companies in the country for solar contract deals.

What’s the name of the company? If they advertise it as 6.5kW system, it’s a scam. 

So, I just took a good look at the contract and this is how it is specced in there.

Does this qualify for what was delivered?

The second pic is how it is advertised.

Edited October 19, 20232 yr by justchecking123

They will have to show you the official datasheet where precisely it states that it's 4600W + 1900W for battery charge over and above.
I see nothing like that in this spec sheet.
A 6500W Inverter will supply 6500W, thats the industry standard.

6 hours ago, justchecking123 said:

So, I just took a good look at the contract and this is how it is specced in there.

Does this qualify for what was delivered?

The second pic is how it is advertised.

Usually when we speak of a XkW system, we understand that it can backup X.

The Goodwe that you mention can back up 4.6kW and can charge at 100a. 

The screenshot doesn't mention any brands and doesn't show a Goodwe inverter or pylontech batteries. Ok... That's just illustrative. 

If you've already paid and you are sure about the inverter then you can have a steady 4.6kW backed up. I don't see how they get to 6.5, but also they haven't promised that you can backup 6.5.

Its all a bit vague. 

To be fair, they don't advertise anywhere on that flyer that it is a 6.5kW backup system. They only specify 6.5kW AC and DC charge which is correct for that inverter.

It's a case of obscure marketing and clients not paying attention what the numbers on the advert really mean.

8 minutes ago, PowerUser said:

To be fair, they don't advertise anywhere on that flyer that it is a 6.5kW backup system. They only specify 6.5kW AC and DC charge which is correct for that inverter.

It's a case of obscure marketing and clients not paying attention what the numbers on the advert really mean.

I agree ,as consumers we should be doing more research about the capabilities of these systems before purchasing them. Basically every company uses marketing tricks like these in this day and age (sadly).

"Hybrid inverter 6.5kW combined AC load & DC charge"

This is extremely devious marketing. I would not do business with them. Walk away, if you still can. 

6 minutes ago, PierreJ said:

"Hybrid inverter 6.5kW combined AC load & DC charge"

This is extremely devious marketing. I would not do business with them. Walk away, if you still can. 

Absolutely agree!

While many companies do use sly marketing, this is completely devious and dishonest...

9 hours ago, justchecking123 said:

Thanks, guys.

 

This is what I suspected.

I assume this is how they trick people, since they usually do the installation and then stick the whole thing into a box that prevents you from seeing what equipment is actually in there.

 

I'm now torn between demanding they bring me what I paid for, or cancelling the entire deal, since I don't want to deal with untrustworthy companies.

 

The worst part is that this is supposedly one of the top rated companies in the country for solar contract deals.

Before cancelling the deal, I would first check what they charged me and compare the prices with other suppliers. It might shock you to see that the price they gave you is deal of a life time and you might reconsider. On the flip side, they might have over priced their package and if that is the case then you can demand that they supply what you have paid for, or cancel the deal. 

10 hours ago, zsde said:

A 6,5kW Inverter will be able to supply 6,5kW either from Solar or batteries. This inverter can only only supply 4600W.

This is not correct. It can invert DC to AC 5kW+..BUT only invert 4.6kW on backup side.

I have seen 5,5kW on occasion, but it seems to sit at around 4.8kW nominal.

When charging the battery, DC bus, + DC to AC it will go over 5kW easily.

However, the goodwe comes out in a 6kW version as well, so maybe the wires got crossed there.

Frankly, are you sure it's a new inverter because they're more expensive than a 5kW sunsync..

I think your installer is not to be trusted.

28 minutes ago, FixAMess said:

I have seen 5,5kW on occasion, but it seems to sit at around 4.8kW nominal.

It can only output 20A. Everything it reports above that (4600W at 230V) is internal losses. (the only exception is for periods shorter than 10s).

Edited October 20, 20232 yr by P1000

2 hours ago, markus_m2 said:

Absolutely agree!

While many companies do use sly marketing, this is completely devious and dishonest...

It's maybe devious in not stating the performance in the format that the average customer would have expected to see it, but they are not lying outright either.

On 2023/10/20 at 11:24 AM, P1000 said:

On 2023/10/20 at 10:56 AM, FixAMess said:

I have seen 5,5kW on occasion, but it seems to sit at around 4.8kW nominal.

It can only output 20A

Correct, and 20Ax240V = 4.8kW, not 4.6kW..When pushing back to grid I've seen 250V x 19A-20A over an extended period. At 255V the inverter restarts..

 

So I had another look today and found something rather interesting on the Goodwe reporting...

On the power flow diagram it shows 4764W from panels and 4790W (Battery+25W) into loads BUT on the details page it shows only converting Output Power 4595W!! Maybe @P1000 has a point! Seems not even Goodwe can make its mind up as to just how much power it can deliver to loads...

Edited October 22, 20232 yr by FixAMess
Clarification

Thanks very much for everyone's comments and input.

I raised all this with the company, and they agreed that the marketing was misleading but assured me that it was not intentional, but rather a matter of tech people writing the marketing material. Their site has been updated and they've committed to replacing my inverter with a 6 Kw (AC load) model.

Edited October 20, 20232 yr by justchecking123

1 hour ago, justchecking123 said:

Thanks very much for everyone's comments and input.

I raised all this with the company, and they agreed that the marketing was misleading but assured me that it was not intentional, but rather a matter of tech people writing the marketing material. Their site has been updated and they've committed to replacing my inverter with a 6 Kw (AC load) model.

That is a refressing response

Edited October 20, 20232 yr by I84RiS

3 hours ago, justchecking123 said:

Thanks very much for everyone's comments and input.

I raised all this with the company, and they agreed that the marketing was misleading but assured me that it was not intentional, but rather a matter of tech people writing the marketing material. Their site has been updated and they've committed to replacing my inverter with a 6 Kw (AC load) model.

Make sure you get a 6kw Inverter.. That AC load text is just misleading. They should tell you the model number of that inverter.

To meet the specification they are selling, you need the Goodwe GW6000 ES20 installed. The Goodwe GW5048D_ES is the older model from this series and it is about to be discontinued. 

 

https://en.goodwe.com/Ftp/EN/Downloads/Datasheet/GW_ES G2_Datasheet-EN.pdf

Very late late response, the GW5048D-ES was a good buy back in 2020 given what was available back then. The ad might have been misleading, but it can blend power when the grid is on and give up to 40amps at 230v which is where the 9200W comes from. Mine has run on close to 8000W on grid without issues. The down side is off grid it's only rated at 22amps which is atound 4800W. Depending on the price and your need you can't go wrong with it and 5 x 2000W pylon techs!

These days a Dye or sunsynk is probably a better option since they allow generator input which is a bonus if you want to go off grid and top up with a genny.