Microinverters for high-output panels?

[fafrd]

With the new generation of high-power panels exceeding 500W and even 550W, I’m interested in understanding whether there are any Microinverters out there compatible with these new high-power panels?

For example, Santan Solar is currently offering this 530W panel from JA: https://www.prosunsolar.com.au/news...7/JAM72S30-MR-510-530-Global_EN_20200429A.pdf

Voc is 49.65V @ 25C and after calculating for a minimum of 0C, increases to just over 53.0V, so a maximum voltage limit of at least 55V if not 60V seems like the trickiest requirement.

Is anybody out there using a Microinverter with a maximum voltage of at least 55V or higher and output level of 500-600W?

NEP has announced their ‘Macroinverter’ which is targeting exactly this application: https://northernep.com/blog/nep-mac...-the-first-microinverter-for-next-generation/

It was announced last year but I’ve not yet seen it available anywhere, hence the thread to understand whether their are any other ‘high-output-panel’ Microinverters that anyone on the Forum is already using…

 

[meetyg]

I have the Deye SUN 2000W G3 microinverter, which has 4 individual MPPT inputs (actually mine is a rebranding, but exactly the same as the Deye).

I have 2 Lingo 455w panels connected to it (one on each input) and another 4x100w flexible panels connected to the third input (these 4 panels are connected 2s2p).

It works great for now (running for about two months now) and the app/web site can show you current and historical power output of each input. Lots of info can be displayed (amps, volts and power/wattage) on the app.

Previously I had problems with another (cheaper) microinverter (GTB-1200W). It was rated for 1200w total (also 4 separate inputs) and 50v max voltage per input, but for some reason it didn't play well with the 455w panels (tripped the overvoltage protection, even though voltage was less than 50v per panel).

The Deye is rated for max of 60v per input, suitable for 60-72 cell panels.
I'm really impressed with it for now, I hope it will have a long lifetime.

Here are some specs (as mentioned I have the 2000w version for EU) :


You can get more info here:

SUN1300-2000G3-US-220/EU-230 | 1300-2000W | Single Phase | 4 MPPT | Micro-inverter | Rapid Shutdown Inverter Company, Supplier | Deye Inverter Technology

NingBo Deye Inverter Technology Co.,Ltd is China SUN1300-2000G3-US-220/EU-230 | 1300-2000W | Single Phase | 4 MPPT | Micro-inverter | Rapid Shutdown inverter company and supplier。 The SUN 1300-2000G3 is a new generation grid-tied microinverter with intelligent networking and monitoring sys...

www.deyeinverter.com

BTW, there are rebranded versions of this microinverter on Aliexpress. If you are interested I will send a link from where I bought mine.

 

[fafrd]

I have the Deye SUN 2000W G3 microinverter, which has 4 individual MPPT inputs (actually mine is a rebranding, but exactly the same as the Deye).

I have 2 Lingo 455w panels connected to it (one on each input) and another 4x100w flexible panels connected to the third input (these 4 panels are connected 2s2p).

It works great for now (running for about two months now) and the app/web site can show you current and historical power output of each input. Lots of info can be displayed (amps, volts and power/wattage) on the app.

Previously I had problems with another (cheaper) microinverter (GTB-1200W). It was rated for 1200w total (also 4 separate inputs) and 50v max voltage per input, but for some reason it didn't play well with the 455w panels (tripped the overvoltage protection, even though voltage was less than 50v per panel).

The Deye is rated for max of 60v per input, suitable for 60-72 cell panels.
I'm really impressed with it for now, I hope it will have a long lifetime.

Here are some specs (as mentioned I have the 2000w version for EU) :
View attachment 69648

You can get more info here:

SUN1300-2000G3-US-220/EU-230 | 1300-2000W | Single Phase | 4 MPPT | Micro-inverter | Rapid Shutdown Inverter Company, Supplier | Deye Inverter Technology

NingBo Deye Inverter Technology Co.,Ltd is China SUN1300-2000G3-US-220/EU-230 | 1300-2000W | Single Phase | 4 MPPT | Micro-inverter | Rapid Shutdown inverter company and supplier。 The SUN 1300-2000G3 is a new generation grid-tied microinverter with intelligent networking and monitoring sys...

www.deyeinverter.com

BTW, there are rebranded versions of this microinverter on Aliexpress. If you are interested I will send a link from where I bought mine.

That s for the recommendation - exactly what I was hoping for when I started the thread.

So no problems operating with US 240V / 60Hz grid, right?

And quality of build seems roughly on a par with that of other Microinverters?

I am interested in your AliExpress vendor if you were happy with them. Feel free to PM me if you don’t want to post here.

 

[meetyg]

I am using the EU version (230v, 50hz) but it seems they have a US version too.

It's build quality seems good, and has massive heat dissipating fins.
It took me some time to setup the WIFI connection and get the app setup, but it's worth it. The details you get are on another level compared to those cheap no-name microinverters.

I forgot to mention that I keep mine a few meters from my panels, where there is shade. The reason that I didn't mount it directly under the panels is because my panels are lying fairly flat on my pergola, and there is little airflow. Having that during the summer it can get very hot here in the Middle East, I prefer it be more ventilated and in the shade, just to prolong its lifespan.

It will still heat up a bit during peak hours, but it works with no problem, and doesn't stop producing power.

I got it from here:

294.69US $ 30% OFF|2000w Inmetro Grid Tie Solar Inverter 4 Mppt Micro Inversor Solar Panel 230vac 240v 60hz With Built-in Wifi Microinversor - Solar Inverters - AliExpress

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

Thus is the EU version, but maybe the seller also has the US version.

It's around $400, but if you compare it to other microinverters, that have only one MPPT input, I think it's a good deal.
You may want to get the "original" Deye branded one, depending on its availability on Amazon or Ebay.
I got mine from Aliexpress because I couldn't find it elsewhere with shipping to my region.

Good luck and keep us updated!

 

[fafrd]

I am using the EU version (230v, 50hz) but it seems they have a US version too.

The ‘EU’ version of the G3 is 230VAC but supports a range of 184-265VAC and 45-65Hz, while in addition to a similar ‘EU’ version, Deye seems to be offering 2 ‘US’ versions of their previous-generation G2:

SUN1200G-230-EU
184-265VAC
45-55Hz

SUN1300G2-US-208/240
183-264VAC
55-65Hz

SUN1300G
176-242VAC
55-65Hz

Compared to the 1300W version of the G3 model you have:

SUN1300G3-EU-230
185-265V
45-65Hz

This is basically the same as the SUN1300G2-US-208/240 with an expanded frequency range to also support the 50Hz grid of Europe.

They also list a US model of the G3;

SUN1300G3-US-220
176-242V
45-65Hz

So this seems to basically be the same as the SUN1300G with the same expanded frequency range to also support 50Hz grid signal.

So it appears to me that the G2 generation primarily differentiated US from EU versions based on frequency and since the G3 EU version seems to encompass the full frequency range needed to suppport either EU/50Hz or US/60Hz grid, I’m wondering whether the EU model you have will work fine here in the US is not…

The grid where I live in the US is 240V, so the ‘EU’ version of the SUN-G3 is actually a better fit for me than the lower-voltage ‘US’ version which would be maxing-out to support my grid voltage…

It's build quality seems good, and has massive heat dissipating fins.
It took me some time to setup the WIFI connection and get the app setup, but it's worth it. The details you get are on another level compared to those cheap no-name microinverters.

Not a big priority for me but if it is built in and ‘free’ (just an app), nice to have.

My existing mucroinvetter array (NEP) needs a ‘gateway’ to communicate with the Microinverters through PLC and it cost about $350…

I forgot to mention that I keep mine a few meters from my panels, where there is shade. The reason that I didn't mount it directly under the panels is because my panels are lying fairly flat on my pergola, and there is little airflow. Having that during the summer it can get very hot here in the Middle East, I prefer it be more ventilated and in the shade, just to prolong its lifespan.

I’m actually considering setting mine up in the basement ~20 meters from the panels, so overheating should not be an issue.

Depending on cost, I’m also planning on oversizing (so up to a 2000W Microinverter for a single 550W panel. The unused inputs will give me an expansion path for the future…

It will still heat up a bit during peak hours, but it works with no problem, and doesn't stop producing power.

What is the peak output you are getting from your unit? A full 2kW?

I got it from here:

294.69US $ 30% OFF|2000w Inmetro Grid Tie Solar Inverter 4 Mppt Micro Inversor Solar Panel 230vac 240v 60hz With Built-in Wifi Microinversor - Solar Inverters - AliExpress

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

Thus is the EU version, but maybe the seller also has the US version.

It's around $400, but if you compare it to other microinverters, that have only one MPPT input, I think it's a good deal.

Thanks for the link. $400 is more than I’m hoping to spend but between stepping back to the 1300W or 1600W model of the G3 could get me closer to my budget.

You may want to get the "original" Deye branded one, depending on its availability on Amazon or Ebay.
I got mine from Aliexpress because I couldn't find it elsewhere with shipping to my region.

Good luck and keep us updated!

I appreciate to info and will report back when I have news, but it could be a while. I’m just starting the research phase for an expansion I’m planning for ~2023.

I have NEP Microinverters and saw their announcement for their ‘MacroInverter’ which had been the only option I had found (and has not yet reached the market).

These Deye G3 Microinverters mean I can start planning for a Microinverter-based architecture confident that there should be at least 2 quality products to choose from once the time comes.

If cost and power is equal, the NEP Macroinverter (600W) offers compatibility with my existing gateway, so that’ll probably be the way I’ll go. But if for the same price I can purchase a single-input 600W Microinverter from NEP I can get a 4-input or even 2-input Microinverter from Deye (or rebadger) with double or more the peak output level (meaning more headroom), that sounds like a wiser investment.

I just need to understand whether there is anything more to the whole ‘US’ versus ‘EU’ comparability thing other than voltage range and frequency…

 

[meetyg]

The ‘EU’ version of the G3 is 230VAC but supports a range of 184-265VAC and 45-65Hz, while in addition to a similar ‘EU’ version, Deye seems to be offering 2 ‘US’ versions of their previous-generation G2:

SUN1200G-230-EU
184-265VAC
45-55Hz

SUN1300G2-US-208/240
183-264VAC
55-65Hz

SUN1300G
176-242VAC
55-65Hz

Compared to the 1300W version of the G3 model you have:

SUN1300G3-EU-230
185-265V
45-65Hz

This is basically the same as the SUN1300G2-US-208/240 with an expanded frequency range to also support the 50Hz grid of Europe.

They also list a US model of the G3;

SUN1300G3-US-220
176-242V
45-65Hz

So this seems to basically be the same as the SUN1300G with the same expanded frequency range to also support 50Hz grid signal.

So it appears to me that the G2 generation primarily differentiated US from EU versions based on frequency and since the G3 EU version seems to encompass the full frequency range needed to suppport either EU/50Hz or US/60Hz grid, I’m wondering whether the EU model you have will work fine here in the US is not…

The grid where I live in the US is 240V, so the ‘EU’ version of the SUN-G3 is actually a better fit for me than the lower-voltage ‘US’ version which would be maxing-out to support my grid voltage…


Not a big priority for me but if it is built in and ‘free’ (just an app), nice to have.

My existing mucroinvetter array (NEP) needs a ‘gateway’ to communicate with the Microinverters through PLC and it cost about $350…

I’m actually considering setting mine up in the basement ~20 meters from the panels, so overheating should not be an issue.

Depending on cost, I’m also planning on oversizing (so up to a 2000W Microinverter for a single 550W panel. The unused inputs will give me an expansion path for the future…

What is the peak output you are getting from your unit? A full 2kW?

Thanks for the link. $400 is more than I’m hoping to spend but between stepping back to the 1300W or 1600W model of the G3 could get me closer to my budget.

I appreciate to info and will report back when I have news, but it could be a while. I’m just starting the research phase for an expansion I’m planning for ~2023.

I have NEP Microinverters and saw their announcement for their ‘MacroInverter’ which had been the only option I had found (and has not yet reached the market).

These Deye G3 Microinverters mean I can start planning for a Microinverter-based architecture confident that there should be at least 2 quality products to choose from once the time comes.

If cost and power is equal, the NEP Macroinverter (600W) offers compatibility with my existing gateway, so that’ll probably be the way I’ll go. But if for the same price I can purchase a single-input 600W Microinverter from NEP I can get a 4-input or even 2-input Microinverter from Deye (or rebadger) with double or more the peak output level (meaning more headroom), that sounds like a wiser investment.

I just need to understand whether there is anything more to the whole ‘US’ versus ‘EU’ comparability thing other than voltage range and frequency…

There may be some differences of earthing/grounding methods between the EU and US versions.
This could affect some of the microinverters safety measures.
I have seen that sometimes in the US, the earth/ground is bonded to neutral. If you did that in EU type systems, that will cause a ground fault.

Maybe you should contact Deye to better understand the differences.

I only have around 1300w DC peak of solar (STC rating) on my pergola, but the most I got momentarily from the inverter was around 800w AC. But it's not the inverters fault. It's actually better than I got with other cheap ones.

The problem is my setup:
1. My pergola is facing East, and so are my panels. I get sun on my pergola during morning and noon hours, but after that I get shading from my building.

2. My 455w panels lay almost flat on my pergola so they get less airflow and therefore heat up during peak hours, producing less power. I could have mounted them at an angle, but then they would be more shaded by the building on afternoon hours.

3. My 4x100w panels are flexible panels, which are mounted at about a 45° angle (which is good) but these panels are no where near their STC rating. They also have some airflow but not enough.
Because these panels and the glass panels are at different angles, I don't get peak of both at the same time of day.

But I'm pretty happy with the daily production of ~3.8KWh. I installed the 2000w microinverter just two months ago, so I'm guessing that during the summer I will be producing maybe close to 5KWh daily, with those longer summer days.

BTW It is often recommended to "overpanel" your system. Meaning that if the inverter can handle 2000w, your panels ratings should be around 2400 on order to actually get that 2000w. As long as you don't go over the recommended voltages and amps for the microinverter you should be fine.
Deye even states this by saying that max output of a panel can be 600w.
600 times 4 is 2400w.

In general, inverters are most efficient when they run at a higher percentage of their max rating, rather than lower.
For example, if you run an inverter with 50% load, it will run less eficient than if you were to run it with 80% load.

 

[fafrd]

There may be some differences of earthing/grounding methods between the EU and US versions.
This could affect some of the microinverters safety measures.
I have seen that sometimes in the US, the earth/ground is bonded to neutral. If you did that in EU type systems, that will cause a ground fault.

Maybe you should contact Deye to better understand the differences.

That’s good advice (or at least wait until I’ve found confirmation of other US-based DIYers successfully using those products here).

I only have around 1300w DC peak of solar (STC rating) on my pergola, but the most I got momentarily from the inverter was around 800w AC. But it's not the inverters fault. It's actually better than I got with other cheap ones.

Yes, the only way you can rate the efficiency of your inverter is to characterize the incoming amperage (and current). I pretty much never exceed 85% of nameplate rating on my existing 4kW Microinverter-based array…

The problem is my setup:
1. My pergola is facing East, and so are my panels. I get sun on my pergola during morning and noon hours, but after that I get shading from my building.

2. My 455w panels lay almost flat on my pergola so they get less airflow and therefore heat up during peak hours, producing less power. I could have mounted them at an angle, but then they would be more shaded by the building on afternoon hours.

3. My 4x100w panels are flexible panels, which are mounted at about a 45° angle (which is good) but these panels are no where near their STC rating. They also have some airflow but not enough.
Because these panels and the glass panels are at different angles, I don't get peak of both at the same time of day.

But I'm pretty happy with the daily production of ~3.8KWh. I installed the 2000w microinverter just two months ago, so I'm guessing that during the summer I will be producing maybe close to 5KWh daily, with those longer summer days.

BTW It is often recommended to "overpanel" your system. Meaning that if the inverter can handle 2000w, your panels ratings should be around 2400 on order to actually get that 2000w. As long as you don't go over the recommended voltages and amps for the microinverter you should be fine.
Deye even states this by saying that max output of a panel can be 600w.
600 times 4 is 2400w.

Yes, my existing array is 34% over-paneled (335W panels on 250W Microinverters) and at most, I clip ~14% of potential energy for the highest-production ~hour of the day…

In general, inverters are most efficient when they run at a higher percentage of their max rating, rather than lower.
For example, if you run an inverter with 50% load, it will run less eficient than if you were to run it with 80% load.

I did not know that and based on that input, a 500W NEP ‘Macroinverter’ will be a better fit for my needs than a 2kW Deye (so I need to forget about the ability to increase number of panels in the future).

If Deye offers an equivalent 500-600W microinverter, I might consider it but only if it’s ~half the cost and proven compatible with the US grid.

Thanks for all your insights.

[EDIT: and by the way, where did you get the information that Microinverter efficiency drops when input power drops to ~50% of rated maximum?]

 

[fafrd]

This paper seems to suggest that Microinverter efficiency varies more as a function of temperature (higher is better) than as a function of input power: https://www.osti.gov/servlets/purl/1146323

 

[meetyg]

This paper seems to suggest that Microinverter efficiency varies more as a function of temperature (higher is better) than as a function of input power: https://www.osti.gov/servlets/purl/1146323

That's interesting...
Most microinverters will have a high temperature threshold, were they will either lower the output, or stop altogether for a few minutes, to cool down.
So we need to stay below that threshold.
Running and inverter at high temperatures will also shorten its lifespan, so that's another thing to take into consideration.

 

[meetyg]

by the way, where did you get the information that Microinverter efficiency drops when input power drops to ~50% of rated maximum?

Well, I wasn't exact with the numbers, but it's fairly well known.
You can see this guy's tests for example. He shows that at different load levels, the efficiency changes.

Some sites state that below 15% load, the efficiency is affected most.
This site also shows a graph, although the peak they show is around 30% load.
I still thinks that's a low load for peak efficiency. But then again every inverter has its own specs.
[Source: https://www.e-education.psu.edu/eme812/node/738]

I believe that efficiency at higher load rates goes down a bit, more due to excessive heat, rather than conversion efficiency.

 

[meetyg]

Another disadvantage to larger "MacroInverters" or string inverters that have only one two MPPT inputs, is that they won't be able to optimize the output for each panel.
If you have some shading at times of the day on some panels, total output maybe affected more on a string/macro inverter.

Also, some string inverters have a higher minimum voltage, so you will need to connect panels in series in order to reach those voltages, which may not be optimal, depending on your setup (panel placement, shading, etc...).

 

[fafrd]

That's interesting...
Most microinverters will have a high temperature threshold, were they will either lower the output, or stop altogether for a few minutes, to cool down.
So we need to stay below that threshold.
Running and inverter at high temperatures will also shorten its lifespan, so that's another thing to take into consideration.

Yes, Microinverters cannot overheat and generally have protection circuitry to avoid overheating. My NEP BDM300x2 Microinverters have 600W peak output but only 500W sustained output rating,

On a very high-productivity day, I can see my Microinverters creep past 500W approaching 600W of output but they are only able to sustain that output level for ~1 hour before I can see them throttle-back to 500W.

But that is only cutting back output to avoid overheating / damage. Conversion efficiency itself may well increase with increasing temperature (as that paper suggested)…

 

[fafrd]

Well, I wasn't exact with the numbers, but it's fairly well known.
You can see this guy's tests for example. He shows that at different load levels, the efficiency changes.

Some sites state that below 15% load, the efficiency is affected most.

Below 15% or even 30%, I agree with you. It was your earlier statement that efficiency was lower at 50% than 100% that had me curious. I’m considering getting a Deye 2kW inverter for a total only one 550W panel of input (for now), so efficiency at 25-50% of rating is what is most important for me.

This site also shows a graph, although the peak they show is around 30% load.
I still thinks that's a low load for peak efficiency. But then again every inverter has its own specs.
[Source: https://www.e-education.psu.edu/eme812/node/738]

I believe that efficiency at higher load rates goes down a bit, more due to excessive heat, rather than conversion efficiency.

So first, thanks for the link and the graph.

But second, that graph indicates conversion efficiency at 50% is roughly ~103% of conversion efficiency at 100%. And in any case, for my needs, anything within 90% of peak conversion efficiency is ‘good enough’ so that graph suggests I’ll be OK with anything above 10% of peak output levels (0.2kW).

But lastly, I suspect that data may be for a PSW inverter where output level is limited by load demand, not available input power.

For a non-grid-tie PSW inverter, standby power consumption is a consideration that especially impacts conversion efficiency at very low output levels (meaning very low load demand).

Grid-tied Micro-inverters are different because they essentially convert as much incoming power as they can and send it to the grid, so I suspect conversion efficiency at very low output levels may actually drop by less than that graph suggest…

But in any case, if I can be reasonably confident that conversion efficiency of a quad-MPPT Deye Microinverter with only one 550W panel connected will be within 90% of max efficiency rating of 95% (meaning no lower than 85.5%), that’s good enough for me to invest in the ‘headroom’ for if/when I want to add another panel or two…

 

[fafrd]

Another disadvantage to larger "MacroInverters" or string inverters that have only one two MPPT inputs, is that they won't be able to optimize the output for each panel.

Actually, NEP coined the term ‘Macroinverter’ to refer to single-MPPT Microinverters designed to handle the new larger-format panels rated for 500W or above.

They essentially took the 300x2 Microinverter designed to connect to 2 300W panels and redesigned it to handle a single panel of up to 600W instead.

So it is not a string inverter.

String inverters typically handle much higher string voltages than Microinverters.

So a ‘Macroinverter’ is not a string inverter, it is a Microinverter designed to handle max voltage of 60V (compared to typical Microinverters which handle max voltage levels of 50 or 55V) as well as max output levels of 500-600W per panel/input (compared to typical Microinverters which max out at 250W or at most 300W per input/panel).

If you have some shading at times of the day on some panels, total output maybe affected more on a string/macro inverter.

Also, some string inverters have a higher minimum voltage, so you will need to connect panels in series in order to reach those voltages, which may not be optimal, depending on your setup (panel placement, shading, etc...).

Yes, don’t worry, I’m well-versed in the advantages of Microinverters over string inverters for shading.

My AC-coupled 4kW grid-tied array is Microinverter-based (NEP) and my new DC-coupled 1kW array is based on a 1S string of 3 half-cut panels (so it is essentially a 6P1S array of half-panels) precisely to maximize output in the presence of partial (and moving) shade.

I’ve now basically got the battery-charging backup-power side of the equation solved now and so I’m thinking that any new panels I add in the future would be more affective as additional AC-coupled output.

With a quad-input 2kW Deye Microinverter (or ‘Macroinverter’ to adopt NEP’s parlance), I can add a single panel to start and have the headroom to add another 1-3 panels in the future (once we actually have our new EV and understand how much our consumption has increased).

I’ve not seen any other Forum members using Deye Microinverters, so I appreciate your inputs…