Opinions on Inverters

Hey guys, 

New to this forum.  Thought I'd introduce myself and see if I can garner some opinions...

I have a 19.34kW array in Louisiana that was installed in 2009. 92x Kyocera 210W panels connected to 4x Fronius IG-Plus 5kW inverters (long story with crazy early Louisiana politics).  System has been working great and has recovered it's Capex...Ya!!!  No performance problems at all.  It's starting to see a lot of service degradation over the years, which is normal, so I'm looking to augment the system in light of my utility (Entergy) has begun hammering North Louisiana residents with recovery fees following the hurricanes.

I plan to move my south panels to my west roof and add about another 15-18kW.  Still shopping panels.  What I'm really studying now is inverters.  I thought I made my mind up that I was going with a Sol-Ark 15K, but the price tag has me saying...let's shop a little bit more.  I like the ability to add batteries and a generator.  My house is wired for a 12kW generator, which you can see my setup on YT.  I set this up and made the videos to help some fellow Louisiana friends who were impacted by Hurricane Laura.

So my Q...what are the best options for inverters in the 15K-20K range with battery/generator connectivity that is comparable in price or better to Sol-Ark?  


  • BB.
    BB. Super Moderators, Administrators Posts: 33,533 admin
    I don't have any recommendations for inverters... But a question about service degradation.

    Are you talking about utilty service issues (more brownouts/blackouts recently)?

    Or are you saying that your solar power system is harvesting less energy than it has in the past? If this, you might want to check your solar array wiring for any failed electrical connections, failing panels, dirt on panels, or shading from growing trees.

    A quick method is to purchase an AC+DC current clamp DMM (digital multi-meter). During the middle of the day, you can set to DC mode and measure the current from each array (very handy if you have two or more strings in parallel going to a single solar input on your inverter). All it takes is for one panel to fail, or one electrical connection to corrode/come loose to kill the current for that string and reduce your overall solar output.

    https://www.amazon.com/UNI-T-Digital-Handheld-Resistance-Capacitance/dp/B0188WD1NE (low cost meter)
    https://www.amazon.com/Auto-Ranging-Resistance-Klein-Tools-CL800/dp/B019CY4FB4 (mid-cost meter)

    Note that there are AC only current clamp meters, and AC+DC clamp meters. Both types are fine meters, but the AC+DC is very handy to use on solar power systems (DC for solar panels+battery systems, and AC for standard 120/240 VAC circuits).

    With multiple strings, it is pretty quick and easy to see which string(s) may be failing to provide its power.

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SolarCzar
    SolarCzar Registered Users Posts: 2

    No, let me clarify.  My current system is working fine. I test regularly and I keep the panels clean, etc..  Solar panels will naturally degrade in performance over time.  No panel will operate at 100% efficiency forever.  Most manufacturers guarantee 80% performance around 20 yrs.  Most tell you to expect ~1% degradation loss Year over Year.  My Kyocera panels when new were a 14% efficient panel.  Most panels today are closer to 20% efficient.  No, My system is 14yrs old and it's doing the best it can.  When installed, it provided ~70% offset of my annual $$ power billing.  Now with working more from home, inflation, fuel increases, hurricane recovery, etc...that number is closer to 50% and continuing to drop as the system ages.  It's not worth replacing the panels/inverters and discarding them, as there is still some life left in them and I plan to ride them to the end or until a better deal comes around.

    In the meantime, I have already decided to augment my system to rejuvenate my overall power production and use the cost paid to the utility as the business case justification to offset the capital for the new system.