Solar Power Austria | SolarEdge 3680 HD Wave & LG Chem Resu

Here in Austria the photovoltaic system is fairly “heavy” supported by state. You could get a subsidies for the complete system. Quite a bit for the battery part (50% of costs), panel parts approximately 20%.
One might be lucky and get the subsidies, but might also happen that you won’t get them. There is quite bit of bureaucracy behind, so it might be quite comfortable to outsource it elsewhere. You also get 12 - 25 year warranty.

I have been explained that the 5kWp & 10kWh are a good combination for a 4 person family :slight_smile:

I am not much familiar with the systems and how are they all called, But the offer is system 1. panels 5kWp (the rest of not used electricity is sold back to the distribution grid) or also combined with the 2. battery system 10kWh that will charge the battery and than the rest will be sold back to grid

So I would like to review the quotes and get inside if the quotes are feasible.

  1. Panel System 5kWp
  • Hardware … … … … … … … … … 5610 €
    18x GCL P6/60 275W
    18x SolarEdge P300-5
    1x SolarEdge 3680 HD Wave
  • Installation costs… … … … … … … 2270 €
  • Subsidies … … … … … … … … … -1240 €
    Sum … … … … … … … … … … … 6640 €
  1. Battery System 10kWh
  • Hardware … … … … … … … … … 6700 €
    LG Chem Resu 10H / 9,3kWh
    StorEdge Sesti S4
    SolarEdge Modbus 50-100A
  • Installation costs … … … … … … … 730 €
  • Subsidies … … … … … … … … … -4650 €
    Sum … … … … … … … … … … … 2780 €

So the total costs for the both systems 9480€ + 20% Tax, so roughly 11 400€

Is this the win win situation or would I be ever able to get something similar with reduced costs. Only the installation costs are 3000€. I am not sure about the component costs if the provided prices makes sense.
How much of those % of those 5kWp / 10kWh I would be able to use and how much I would have to sell back to grid. Are there any comparable systems that I would not have to be selling back to grid?

Another detail is that Austria has not so much sun as Australia or even Spain. So would the investment be worth and renting within X years?

thanks a lot for any help!!!


Hi there @hramat

Thanks for posting, that’s very interesting insight into the Austrian solar market. I am surprised by how heavily the battery system is subsidised, compared to the solar system.

Regarding sunlight, I think you’ll get enough. You won’t get much over winter of course, but probably 15kWh a day on average with a 5kWp solar system. The sizing seems fine, but @Svarky would be better to answer that.

I think pricing for the battery system is very good, and the components are all good. The solar system price is higher than we would pay here, but our subsidies on the solar panels are higher. It is not too expensive I think, and the SolarEdge products are good, useful to have the optimisers. My only concern would be with the panels, I am not very familiar with GLC. If you are going to spend ~ 10k€ I think it’s worth getting some top quality panels. See if you can get an option that is on our top 10 list:

Is it worth the investment? There’s a lot to weigh up there. But assuming that you can offset every kWh that your system generates, you could do a (very) rough calculation by assuming a 15kWh reduction per day from your electricity bill and see how long that would take to pay off the system.

Hope that helps. Please keep us updated, very interested to hear how it turns out.

By the way, have you read our Guide To Buying Solar? It’s a good place to start.


hello Marty

Thank you very much for you fast response.

Yes, the batteries are highly subsidized mainly this year, it seems that someone have made a mistake and they have not change it afterwards. The panels are lower subsidized because the subsidies are running already for some year and they are getting lower each year. I guess battery systems are fairly new and therefore higher subsidized. It is for sure that next year would be both lower again.

I have been checking our electricity usage and we had those years we live in this house 22 & 28 kWh/Day (<10 000 kWh/Year). So if I would be able to save 15kWh. Which would mean a 55 - 70% saving. Bringing the investment roughly in 14 years back.
When I submit the higher usage, they have reviewed the quote and would rather propose 7kWp / 14kWh.

Thank you for the link to the panels review, I saw the document already, printed it also out and went through, I have also printed from this forum the other component guides. I am not sure why they chose the GCL panels (he said something about QCell but do not remember what), and on internet I found some information about them (cheap, big firm,…). Yes I would also rather go to some well known marks.

Anyway on the new quote for 7kWh he used already QCell Plus G4.3
I will definitely ask details about panels and components, I am also not sure why in Austria some chose other components than Fronius (as Austrian firm).

Earlier mentioned GLC was a typo, sorry for that, should have been GCL

thanks a lot again for help

Yes good point! When I think of Austria, I think of Fronius. It’s funny you have not been quoted with Fronius. Do you have shading issues? SolarEdge has panel level optimisation, which is good if you have any shading issues, or your panels are in an areas where they might get dirty.

QCell should be a good option.

Keep us posted.



good questions, Yes probably we have more shades than in Australia. In summer we have a lot of sun with a little clouds but the winter is fairly cloudy. As you wrote I’ve seen the Solar Edge having some kind of trick. I would also rather like to go with QCell

Anyway, He gave me some discounts on installation but on the other hand submitted a reviewed quote with Solar Edge 5k Battery Inverter for 2000€ which I found on Internet for 1200€, similar way, LG Chem Resu 13 quoted for almost 8000€ which I found on internet for 6000€

will probably search someone else or do it by my self




I am commig for a help again with some more questions.
I am progressing “slowly” further with preparation for the photovoltaic system. I have been checking some details with few more companies in the reqion, to get more technical detail and also some price levels. I would not go for the Baterr for the moment. I would probably go for it later on. (the heavy subsidies I provided earlier seems to be more a marketing tool of politicians as a reality :slight_smile:

I am most probably going for the Fronius Inverter. Some of the companies seen no reason for going for SolarEdge power optimizers (P300-5) as the roof has not shades from trees or other buildings, is directly accesible by sun light. They have told me they have also better experience with Fronius Inverter and the warranty support :slight_smile: better to say little warranty issues.

I am having quite a flat roof - only with 10% - SouthWest oriented. One of the seller has adviced me to take panel without frames (e.g. Trina Dual Glass Panels - Frameless Panels) that the water and dirt would freely float down from the panel. Does this make sense?

Regarding the slope of the roof they adviced me rather to take +1 +2 panel instead of increasing the slope of the panels. Would increasing the slope of the panels improve the performance in winter months or would +1 +2 panels achieve the same? I would like to install the panels direcly on the roof without increasing the slope as it is quite windy in our area.

What makes more sense for such a flat roof - Austria has not so many hot sunny days as Australia so what type of panels would fit better? Roughly said Panels with higher efficiencies? Does the efficiencies increase 19,x -> 20,x makes much differnece in power gain? So in the system is able to produce 15-30kWh/day would the gain be 1% more with higher efficiency panels?

I can install up to 7-8kW (highr kW is not appreciated by state distribution) but my roof area is bigger. Does it make sense to install rather cheaper lower Wattage panels e.g. 13x 270W or the higher Wattage 11x 320W panels. The 13x270W should still be bit cheaper in comparison with 11x320W. Any advantage in reliability or efficiency?

Seems like in the Austria region is the performance during winter months (December, January, February) very low - negligible. So as I am having enough roof area I would rather go for the reliability and performance on lower sunlights rather than efficiency. Are my thoughts correct? Does it make sense???

I have reviewed prices from 5 companies and short comparison for fairly similar ~7kWp PV performance:
Company 1 8500€,
Company 2 9600€
Company 3 11650€

thanks a lot for your help and any thoughts


Well that’s true, but I think it’s both with Fronius, less issues and better support. Unfortunately, even the best inverters still get issues sometimes.

Yeah that does make sense actually, the area around the frames can get pretty funky if low angle, but depends on the environment (trees near by, dust, fungus growing, maybe you don’t have these issues anyway).

You would need to do the math on that, but yes I think it would achieve about the same. The issue is that in winter not only is there less sun, but it’s lower in the sky of course. So a lower angle would increase your summer production, and decrease winter. Does that matter? Do you use more electricity in summer or winter? Maybe you can save more money in summer, and spend more in winter. It’s complicated, but in theory I personally prefer to put more panels than use tilt frames, because of a) aesthetics and b) tilt frames cost as much as 1-2 panels, but don’t produce power themselves. They improve the winter yield, but not the overall yield if that makes sense.

It’s only worth it if you have limited roof space. The panels are priced per watt not per panel. 10kW at 19% will take up a little less space, but cost a fair bit more. However, the more efficient panels, are often also better quality. In the end it’s a cost benefit thing. It’s worth it probably if it doesn’t cost you a lot more. Sorry, I haven’t given any numbers there, but it probably wouldn’t help at this stage.

I sort of answered this above. Higher efficiency often means better quality, but if you have more roof space then efficiency in itself doesn’t matter. But aside from that it makes no difference, you are still installing ~3.5kW based on what you’ve said. Which is a bit confusing, you are talking about being limited to 7-8kW, and considering going higher, but are being quoted for only 3.5kW? Or is it actually 2 x strings of panels, i.e 3.5kW + 3.5kW?

Another point here is important. Are you limited by the output of the system (i.e. the nominal inverter size) or the generation capability (i.e the total panel wattage)? This is important because if it’s output (which it should be, most Australian distributors limit by output, but a couple by generation) then it makes a lot of sense to oversize the inverter, especially in respect to your question above - If you’re worried about output in winter or the angle of the panels, just oversize the inverter. You can and should I think oversize it by about 30%. So if you’re limited to 7kW inverter, get about 9kW of panels. That way in winter, and even in summer when the sun isn’t directly over the panels on a blue sky day, you will generate closer to your maximum amount. This will not negatively effect the inverter, you can check the Fronius specs, it clearly says this is fine.

Sure, it makes sense, but in reality they go together. Really if you want the best low light performance etc, you need to be looking at LG and Sunpower, which also offer best efficiency overall. Their technology is by far the best for these conditions. However, they are expensive, you might find a good balance with REC, or you mentioned Trina, you’ll get good value for money with Trina I think.

Let us know the products that Company 1,2,3 are offering, that might help too.

Good luck!

hi Marty

thank you for your response again, appreciate the help and time you spend!

I have been thinking about my question bit more when I submit them.In general I would probably like to understand if the efficiency means more power gain from similar - or low sunlight. Meaning with higher efficiency panel I would gain more power on winter months as they would be able to transfer more sun light on the electric power. Which you answered on your response. Thanks a lot again,

I use definitelly more power in winter when the temperatures get so low that you just need to heat up the complete house. In summer it is only airconditioning which is not so much a need as the temperatures and humidity are quite ok. Still it is quite nice to have airconditioning for summer months. With earlier years experience we need:
in Total 10 000 kWh/Y
for airconditioning 2 000 - 3 000 kWh/Y in summer (this might be fully covered by PV system)

I started to record in February the daily power usage. In February when temperatures been lower (<-5°C) we had 40kWh. Now in May we got lower usage to 15-20kWh

coming in detail to your answers:

Yes indeed, I was planing to start with 3.5kW and later to add 3.5kW but as the price difference is not that heavy I might go to 7kW from start.Meaning as you wrote 2x strings with 3.5kW+3.5kW. The 8kW is only a option in future if I would like to extended or not - most probably not anymore. I have two roofs (55qm + 20qm) I could use, both heading SW. So I could install more which I might not even need, but due to power grid limitations. Austrian distributor is not allowing officially more than 5kW in reality it is not more then ~7-8kW (or you would have to install voltage monitor :slight_smile:) This is, what you later mentioned as that I am limited by output of the system. This might mean that in summer months I would be producing more than allowed and killing the distribution. Or I could simply plus the one row off in summer :slight_smile:

The cheapest company I am planing to take offered me not Trina but Jinko Cheetah 320W for 210€. I would probably go for them thou having lower efficiency than Trina. I am not sure if the company 1 offers frameless panels. Trina frameless 290W was offered by second company for 225€. I will upload the two quotes later.

Fronius or SolarEdge support might be just a land specific. Fronius should be providing good support in their home country :slight_smile:

Based on your response (good points) and on other suggestions I would leave the 10% slope of the panels and go for 1+2 panels more.

My area might be dusty, it is a village but still 100m from street. The concern I have is that it is quite windy, quite often get up to 100km/h. So not sure if the frameless modules would withstand the winds (for 15-20 years)

looking forward to your response and suggestions

Hi @hramat

Ah, bifacial Trinas. Do you have a white roof? They will generate power on the reverse side as well if you have a light roof. If dark, not so good.

I don’t think that would be a problem if you install flat on the roof. The biggest factor for wind is how far off the roof it is. If you use tilt frames, the panels become like sails, and then you need to be careful about fixtures. I would be interested in what type of racking they use for these frameless panels though. The installers should have clear instructions from racking manufacturer on whether the racking will withstand different wind levels. I’m sure it will be fine, we get cyclones in northern Australia, they just need to use a lot of clamps.


Hi @Marty

The roof is a steel coated plates. Unfortyunately I have not made it white or light or Aluminium (e.g. company Prefa). I have them dark grey but as they are just steel coated plates I could use some mirror like - aluminum foil to improve the power gain :slight_smile:

For fixing they have proposed fixing system IBC TopFix 200 unfortunately only available in German language.
Not sure of the details but for 14 panels they have proposed 14 rails + 48 clamps. I believe this is just similar to any comventional racking (clamping). The rails - racks would in any case be bolted directly to wooden supporting frames of the roof. Attaching that only to roof plates would not be enought.
I might use a frame which I would leave open on the bottom side (so that the panel would be enclosed only on sides and top part) that the dirt and water could freely from out of the panel

I any case I would rather use the panels with frames that the frameless panels would not get deformed by the forces emitted by wind.