What % usage from panels?

System

I have installed 3300 kw of panels, but can only get @ 50% through the inverter. I am going to install sufficient number of panels to increase it to 6000 kw. Any thoughts or help as to why I am only getting @ 50% power output to the inverter.Thanks. L. Dee Oliphant

RCinFLA

Re: What % usage from panels?

6000 kW, that's quite an array!

You need to better define what you mean by 50%. If you mean at high noon you are only getting 50% of rated panel power then that is a bit lacking.

niel

Re: What % usage from panels?

you may need to give more info like the pvs used, wire gauge and length, inverter(s) and if battery backed then the controller(s) and batteries with the total ah and bank voltage.

icarus

Re: What % usage from panels?

We assume you mean 6000 watts of PV, not 6000 kw.

Assuming off grid, you should be in the 75% of name plate rating at solar noon on a good day. How are you measuring? Remember a lot of stuff will have a significant effect yield. For example, in series wired array, a slight shadow on one panel can have a huge effect on total series output.

BB.

Re: What % usage from panels?

Another possibility is you have two high voltage strings in parallel (200-400+VDC), and one of the strings is not providing any power at all.

The simplest check is to purchase a clamp-on DC Amp Meter. Note, an AC clamp current meter is very common but will not work for measuring your DC current from the solar array to the inverter.

For example, this one costs ~$100 new (EBay you may find for 1/2 price).

You may find an open panel, wire, connector, fuse/breaker (if installed), etc.

On a hot sunny summer day, it is not unusual to see only 75-80% of solar array mfg. rated power. Hot days, humidity in the air, hot panels, and highly optimistic solar panel specifications all tend to knock off ~23% or so of noontime rated power.

-Bill