PV output on my 2430w array

[Flunkyboi]

The tilt on my fixed array is set to average year round. Spring Equinox was over a week ago, but because of being busy and weather, etc, I've not really been able to observe it's performance during this optimum time until today.

The particulars:

Six 405w Trina bifacials, seriesed to feed the MPPT controller in an EG4 3kw 48 AIO. My little battery bank is four sereiesed 12.8v 100ah Dumfume LFPs. Temp outside was about 75f at noon. Before noon, I partially Drained battery with PV off before checks to insure the panels were putting out at peak sun. These are bifacial, but get zero back lighting. Sky is sporadic clouds, air is high humidity/tad hazy and the array is a little yellow with the pollen explosion this week. I was taking readings between sneeze fits.

At 12:30, I shut off the draining load (1500w space heater), then turned on the PV. Between the passing clouds, the highest wattage spike from the panels I saw on the EG4 readout was 2150w. Shunt was floating just under 40a going to recharge battery bank.

I'd preferred the panels be squeaky clean, 33° and the sky as cloudless as our Moon, but you take what you get.

Theorectical output is 2430w, but it was 2150 at test time. Is that OK? Thanks.

 

[MisterSandals]

2150W / 2430W = .88

Getting 88% from your panels is great, especially with sub-optimally oriented panels at this time of year.

 

[Flunkyboi]

2150W / 2430W = .88

Getting 88% from your panels is great, especially with sub-optimally oriented panels at this time of year.

I would think if they were set to a tilt favoring the Spring and Fall equinox periods, 29° here, that output would be optimum right now.

 

[rhino]

STC which I'm assuming is what that panel has label on it indicating that 405W is for very specific test conditions of 1000 W/m^2 for solar irradiance and 25°C actual cell temperature, as well at 1.5 air mass. You would not be getting 1000 W/m^2 since you already said it was hazy. Plus the cell temp would have been considerably higher than the air temp especially if they don't have good air flow behind them.

 

[Flunkyboi]

STC which I'm assuming is what that panel has label on it indicating that 405W is for very specific test conditions of 1000 W/m^2 for solar irradiance and 25°C actual cell temperature, as well at 1.5 air mass. You would not be getting 1000 W/m^2 since you already said it was hazy. Plus the cell temp would have been considerably higher than the air temp especially if they don't have good air flow behind them.

The panels are the roof of a purpose built shed. They are well ventilated, but get little or no reflected sunlight from the back.

 

[Glock24]

Well 2150W out of 2430W is very good performance. You can usually expect around 80% of the rates performance, what toy got is higher than that.

Under some circumstances the panel can go higher than their rated output for short periods of time, we're talked a few seconds to a few minutes.

 

[Flunkyboi]

Well 2150W out of 2430W is very good performance. You can usually expect around 80% of the rates performance, what toy got is higher than that.

Under some circumstances the panel can go higher than their rated output for short periods of time, we're talked a few seconds to a few minutes.

A crazy thing like that did happen. I even made a thread about it. One 75° day (one of the warmer days in my testing), I saw the EG4 reporting 2440w. It had been after a day or two of rainy/dreary weather and I'd left the PV off. It was a gin clear day and rain had washed the panels squeaky clean.