Solar Panel Outputs

[Andrew Grace]

Interested to hear feedback on actual real world output from people that are using solar, currently in full sun I am getting around 35 % conversion rate

Ie: if panels are rated at 100 watts the actual power maximum being generated at Midday is 35 watts,

Is this the sort of numbers most are getting near the equator?

[StuM]

Nope, that's very low. Something is wrong, either with your panels or your metering.

A 100W panel in the tropics should be giving you not too far of 100W for several hours in the middle of the day in full sun.

[newhaul]

I'm not in the tropics by any means. ( 49° north ). With sun at a 90° angle we get just over the rated 200 watts of our panels. So if you are only getting 35 watts out of a 100 watt panel there is definately something not right either with your meter or panel setup .

[twinboat]

Here is some real-time data.

At 12:30 today 3/1/16, in Boot Key Harbor, Marathon, FL Keys

I have 675 watts of solar and are seeing 526 watts on my TS 60 MPPT.

[TacomaSailor]

Old (1999) Kyocera 125 watt panels (four) with 1999 Trace C-40 controller (an antique!)

mounted on fixed arch over stern

at 24N (La Paz, BCS, Mexico) April - May
32 amps at 14.4V (460 watts)

29.3N (Puerto Refugio Bahia de Los Angeles, BCN, Mexico) July - September
30 amps at 14.3V (430 watts)

at 18 N (Zihuateneho, Mexico) January - February
29 amps at 14.2V (411 Amps)

[hellosailor]

WRT solar panels, the "conversion rate" actually means what amount of the power falling on the panel is converted to electricity? That is, the energy in the photons falling on the panel, is only partly converted to electrons leaving the panel. 35% would be international news, 20% would be considered grand.


Whether you are getting 35% of your rated maximum output or not...to know if that's a problem, you would have to go over the whole system. Is that 35% being limited by the amount your batteries can absorb? Is there some undersized wiring with poor contacts? Is the measurement itself sure to be accurate, done correctly?


If you put the output form the panels into a load that won't limit them, and it still measures only 35% of the rating, then your panels are failing (or were fraudulently rated) if everything else is eliminated as a possible problem.

[Privilege]

You also have to remember that if your batteries are anywhere close to being fully charged, the controller will only allow a certain amount of amps to flow to your batteries. Are you sure that your controller is showing 'bulk' charging rates?

[TacomaSailor]

The comments about needing a load for the panels are important. All my reported wattage are while simultaneously running:

- 17 amp Spectra water maker
- 5 amp refrigerator
- charging 520 AHr battery bank that was down about 125 AHr

[Rich1950]

I don't look at watts, I watch the amp readings. One 260 panel. And Two 100 watt panels. reading are different all day depending on the suns position, I have two refrigerators, water maker, GPS radio play. at the end of the day my batteries are reading 12.7 , at sun raise my batteries are at 12.5.

[jeepbluetj]

Originally Posted by Rich1950

I don't look at watts, I watch the amp readings. One 260 panel. And Two 100 watt panels. reading are different all day depending on the suns position, I have two refrigerators, water maker, GPS radio play. at the end of the day my batteries are reading 12.7 , at sun raise my batteries are at 12.5.

Y'all do know that amps are directly related to watts?

P = IE

I agree that most folks will monitor the easier to monitor metrics: Amps and volts. But hey, P=IE. (and E=IR) -- and it tells my age for using E.

[s/v Jedi]

Should be measured in kWh per 24-hour period. My record with 660W array is 2.4kWh.

[autumnbreeze27]

I have 8x100w connected to a ms mppt60 and got 3140wh yesterday. Maybe I can run the ac when the sun gets up towards 90? Currently in tenacatita


Sent from somewhere in the Pacific

[StuM]

Originally Posted by s/v Jedi

Should be measured in kWh per 24-hour period. My record with 660W array is 2.4kWh.

That's only 3.6 hours full sun equivalent. Seems low for an average, let along a record.

Whereabouts in paradise are you?

[s/v Jedi]

Originally Posted by StuM

That's only 3.6 hours full sun equivalent. Seems low for an average, let along a record.

Whereabouts in paradise are you?

Panama. Batteries may not have been accepting all the array could give. For tests, batteries should be well down in SOC or a big load.