Possible SolareEdge Inverter Upgrade

KozmoK

Need some advice from the pro's.

My installer installed a SolarEdge SE-6000 last March, and in the summer months I clip/cap out at 6kw for 6-7 hours all summer long.

Here is a typical view of a summer day:

Attachment not found.

Would it be worth it for me to upgrade to the SE7600 Inverter to get those extra kw's I am missing. I know they will add up over years, but does that justify the $2000 + Install pricetag? My installer says its not worth it.

Then I would be left with a backup inverter I can install in case it fails, or somehow resale it (its 9 months old) - or Anyone know of a company that would do this and give me some credit for the turned in inverter?

Thanks!
Scott

solarix

Re: Possible SolareEdge Inverter Upgrade

Without figuring the numbers, I would say its not worth it. Most of the year, its not clipping right? You are losing maybe about 3kWH on a good day, figure with weather that's for 60 days at 12cents per is between $20 and $30 a year. You do the math. Even maybe hard to justify the bigger inverter initially as the 7.6kW SolarEdge is a lot more $$ than the 6kW. At least with SolarEdge you can upsize by just replacing the inverter which is only half the cost of a regular string inverter, but even that would take a long time to pay back. Plus, the existing inverter isn't very marketable as anyone wanting it for a grid-tie is subject to their utility's interconnect rules which require new equipment to be used. Maybe you can find someone with a smaller system with your same problem that wants to upgrade to 6kW, however they would also need to upsize their existing wiring to handle it. There is a real tendency in the solar field to undersize inverters. Yes, the array rating is ideal and is virtually never seen so going 10% undersize on the inverter is ok, but I've seen some real corner cutting with inverter sizing in order to save a few bucks on the quote.
Don't fret - as your system ages you will slowly lose power (.8%/yr) and after a while you won't be clipping.

KozmoK

Re: Possible SolareEdge Inverter Upgrade

Solarix,

I knew in the back of my mind the answer you gave I am in AZ - and its going to clip March-November.

I guess I will have someone come out and tell me if I can add a few more panels with the new inverter to make it worth my while (another row) I have plenty of roof space, and possibly need a breaker panel derate to 150a service to go along with a upgrade.

My winter APS bills have been Nov $45, Dec $48 - most of it was the stupid regulatory fees, other fee's and such, last summer they were $180-200 with two 13 year old AC units running (being replaced in a few months)

Note to others: go with the bigger system to begin with.

solarix wrote: »

Without figuring the numbers, I would say its not worth it. Most of the year, its not clipping right? You are losing maybe about 3kWH on a good day, figure with weather that's for 60 days at 12cents per is between $20 and $30 a year. You do the math. Even maybe hard to justify the bigger inverter initially as the 7.6kW SolarEdge is a lot more $$ than the 6kW. At least with SolarEdge you can upsize by just replacing the inverter which is only half the cost of a regular string inverter, but even that would take a long time to pay back. Plus, the existing inverter isn't very marketable as anyone wanting it for a grid-tie is subject to their utility's interconnect rules which require new equipment to be used. Maybe you can find someone with a smaller system with your same problem that wants to upgrade to 6kW, however they would also need to upsize their existing wiring to handle it. There is a real tendency in the solar field to undersize inverters. Yes, the array rating is ideal and is virtually never seen so going 10% undersize on the inverter is ok, but I've seen some real corner cutting with inverter sizing in order to save a few bucks on the quote.
Don't fret - as your system ages you will slowly lose power (.8%/yr) and after a while you won't be clipping.