Question regarding solar edge product

[wyrepullr]

In one of the earlier posts i saw some info on a product by solar edge called there power optimizer. seems like it is used to stabilize voltages on modules/string lines, by doing max power tracking on individual modules. i checked out the website and think i have an understanding of how they work. my question is for anyone with experience using this product or strong knowledge of it.

I was recently called to a project that was installed by another company. the owner doesn't feel like they are making the kind of power they should.Save the drama they were less than happy with the quality of the install and are concerned the design is not right. It is a 28 kw system roofmounted, In an attempt to be fair to the previous installer i will give only details that are neccesary. these are yingli 230 watt panels, in a 3x13 string config and 3 sma 8000's. there is no documentation available to me so this is the info i have collected. After running this setup thru the sma config tool it does seem to be on the low side of nominal power ratio and gives their conditionally compatible rating. but as i assumed it shows that the minimum voltage is below the inverter starting voltage. i have seen this be an issue when the ambient temps get hotter and the resulting voltages get lower. so i am figuring based on the power usage that they showed me that the system isnt making it's starting voltage on the hot summer days. My question is....is this product by solar edge something that would help fix this issue? thank you inadvance for your thoughts and info.

 

[jaggedben]

I don't have direct experience with Solar Edge. cpicard is the one on this forum who I think has that experience. But I will offer a couple comments:.

- Solar edge optimizers require using a Solar Edge inverter, and switching inverters might not be what you want. Tigo optimizers might be another option to look at. They would work with the SMAs. But I don't know if they would solve your low voltage problem.
- In my opinion, the main purpose of such optimizers is to deal with shading issues and module mismatch. If that is not the problem with this system, it might be more economical to figure out a way to re-wire the system to a better design.
-A quick calc on the yingli 230 voc temp coefficient suggests you must be getting ~90C module temps to miss the start voltage spec. Maybe there is a much simpler and cheaper solution to this problem, i.e. increasing the distance between the panels and the roof to allow better air cooling.

 

[c_picard]

I agree, Solar Edge is probably not the best solution. The only thing you'd get to keep would be the modules.

Those seem like good suggestions, even adding a few modules if you have the space, and re-configuring the strings to better match the inverter? Heck, even less modules in the right setup would get you more power than you're getting when the inverter isn't starting, right?

And boy, 90c is HOT for New Jersey! The hottest I saw in NY was around 70c.

Does this system have a data aquisition setup? On a good day what is it producing? Sometimes customers think that just because they bought a 28Kw system, that's what it will produce, which we know isn't the case.

 

[wyrepullr]

solar edge

solar edge

Thanks guys, i have already reconfigured the string setup, and without changing # of modules i have to already change out the inverters. the 3x13 config just doesn't work well with this sma set-up. i could go to 2x13 with 6000's and leave one set up of 3x13. thats where i ws hoping to use an optimizer type product. The previous installer is no longer in business, and i'mtrying to find an effective solution for the customer.They already have close to a $150,000 into to this.I've discussed removing modules, and they just dont seem to be willing to do this. I understand the concept of less modules more production based on specific design, but having a hard time selling it. Some of it is that they had a bad experience with initial installer and now aren't very trusting or open to solutions.Just a bad situation all around.:happysad:

 

[ggunn]

Thanks guys, i have already reconfigured the string setup, and without changing # of modules i have to already change out the inverters. the 3x13 config just doesn't work well with this sma set-up. i could go to 2x13 with 6000's and leave one set up of 3x13. thats where i ws hoping to use an optimizer type product. The previous installer is no longer in business, and i'mtrying to find an effective solution for the customer.They already have close to a $150,000 into to this.I've discussed removing modules, and they just dont seem to be willing to do this. I understand the concept of less modules more production based on specific design, but having a hard time selling it. Some of it is that they had a bad experience with initial installer and now aren't very trusting or open to solutions.Just a bad situation all around.:happysad:

Having to come in and fix a flawed design where some parameters cannot be changed and the customer is already unhappy is much harder than starting from scratch. I feel your pain.

Consider it part of your education. I am ramping up a project where I had to face similar conditions, and I feel like I should be paying tuition to someone.