Solar Panel Output verse rating

[john61ct]

Originally Posted by PacificGreen

So could it then be concluded that a 600v charge controller would allow panels to be more efficient by having one large string of series connected panels? Certainly series connections are more native to STC conditions then parallel connected panels..

What is STC?

soon as you get a square cm of shade, seagull poop whatever, the whole series will drop output by a LOT

Parallel smaller panels deal with partial shade much better.

Or go a lot of small cheap sub-array controllers one per panel feeding a master.

Extreme is embedded mppt controllers on a chip, within the panel or junction box.

>> ​I am looking for US retail suppliers of JinkoEagle MX, or willing to ship in. Or another vendor (Trinapeak, and "ET COM"?) incorporating embedded "MPPT on each cell string" cell-optimizer ICs from Maxim.

>> Apparently greater management of issues around partial/transient shading, eliminate diodes, DC optimizers and microinverters.

[newhaul]

Originally Posted by PacificGreen

Sorry Stu. I am running 2160watts of solar in a configuration like this:

String Calculator » Morningstar Corporation

But not with a tristar 60 for the controller but with a Coleman Air 440HVA shunting charge controller.

Is there a specific.reason you are using a shunt type solar/wind diversion controller. you would be.better served using a good mppt controller for the solar. If you also have wind then use a diversion controller on the wind only.
Heck you would even do better with a cheap pwm controller than a shunt type controller.

[PacificGreen]

Originally Posted by newhaul

Is there a specific.reason you are using a shunt type solar/wind diversion controller. you would be.better served using a good mppt controller for the solar. If you also have wind then use a diversion controller on the wind only.
Heck you would even do better with a cheap pwm controller than a shunt type controller.

The Coleman Air 440HVA http://www.colemanair.us/shared/Dive...VA_CURRENT.PDF isn't a bad controller at all really. So far as charging lithium batteries it really works quite well. It charges it stop right where you set the voltage.

So far as wind I've simply substituted that with my generator inputs into the 440HVA. Far more reliable and always on when I need it. The 440HVA handles my DC generator loads as well. The controller has a max 125amp continuous duty rating and you won't find that in any other controller.

I'd also like to mention all connections within it are done with ring terminals which I really like.

If you have an efficiency curve the depicts standard charge or shunting charge controllers versus pwm or mppt I would find that a most interesting read. Also the price is quite nice as well. If one day I decide to mount a couple of VAWT turbines on the boat then I have the wind option as well with the controller.

[SV THIRD DAY]

My 320W string on a mppt controller has been averaging 78AH per day for the last 2 weeks.

[StuM]

Originally Posted by SV THIRD DAY

My 320W string on a mppt controller has been averaging 78AH per day for the last 2 weeks.

3.5 hours solar equivalent at 14.4V. Where were you and what was the weather like?

[newhaul]

Originally Posted by SV THIRD DAY

My 320W string on a mppt controller has been averaging 78AH per day for the last 2 weeks.

Sounds kinda low have you had that much cloud cover there in la paz the last couple weeks?

[txg]

Two 140Wp Sunpower panels, freshly cleaned and each with is own MPPT (Votronic), connected with thick cabling to reduce losses (Panels are 28V which further reduces losses), Controllers directly at the batteries with short cable. Mounted on the bimini without any shading except for the backstay.

Currently located in the Carib, according to the battery monitor the maximum output at midday without clouds is 21A at 13,33V which is exactly 280W.

[Jeanneau 45.2]

Originally Posted by SV THIRD DAY

My 320W string on a mppt controller has been averaging 78AH per day for the last 2 weeks.

I agree this seems low. I have 200 watts in parallel (2 x Suaoki 100W 18V 12V Solar Panel Charger SunPower Cell Ultra Thin Flexible from Amazon for $179 each) with a MPPT MidNight Solar Kidd charge controller. In Fort Lauderdale FL right now and averaging 55Ah with panels flat mounted on my Bimini (pure ratio to your 320 watts calculates to 88Ah average). I just received 2 more panels and when I have the 400 watts installed I expect to see double that (again, all four panels mounted flat and not optimized for incident angle) 110 Ah average with best output days at 135 Ah. FWIW, obviously YMMV. Alan

[rom]

Solar panels being rated in W we should probably stick to that and avoid A & Ah to prevent us from making wrong assumptions about battery voltage.

I have 4x 330W Benq* panels divided in 2 arrays of 2 panels in parallel, each array connected to a victron MPPT 150/60. Panels are mounted horizontal. I am currently at about 14.5°N (Martinique) and today I saw a steady 725W around noon on the starboard array. I often have shade on the port array as I am pointing West most of the time. The MPPT monitors show a max output for today of 817 W port array, 816 W starboard array, not sure this really happened, or maybe for a very short time I suppose.

The excellent link given in a previous post (Calculation of Solar Insolation | PVEducation) shows that I should expect 1.04 kW/m2 around noon which is close to STC panel rating. So, I guess I should be very happy considering that I am quite far from the zenith and have horizontal panels !

Giving the total output in kW for the day gathered by the monitor would be useless as my batts are usually full before 10am **

*my understanding is that those are the same as the sunpower E21 but I might be wrong.

**edit: I assume people talking about how much energy per day they are producing have batteries that are always below say 80% SOC.***

***edit again: or they just have little solar per batt capacity, sorry.

[buzzstar]

Originally Posted by txg

Two 140Wp Sunpower panels, freshly cleaned and each with is own MPPT (Votronic), connected with thick cabling to reduce losses (Panels are 28V which further reduces losses), Controllers directly at the batteries with short cable. Mounted on the bimini without any shading except for the backstay.

Currently located in the Carib, according to the battery monitor the maximum output at midday without clouds is 21A at 13,33V which is exactly 280W.

Any chance of convincing you to provide follow up reports, in say, 30, 90, and 180 days?

[txg]

Sure, no problem!

The whole system was installed middle of of august 2016 back in germany, so it is in use for about 200 days now. The maximum output we could see back home was 18A, which declined gradually because the summer ended faster than we were able to sail south. After leaving the canary islands in the end of 2016 and sailing south to cape verdes the output started to increase again.

Today, it was very cloudy on Marie-Galante with a lot of squalls and nearly no direct sunlight. Still, according to the battery monitor the bank was back to 94% when the sun went down which means that the daily output must have been somewhere in the range of about 70-80Ah.

panels are these:
https://www.offgridtec.com/offgridte...k-contact.html
because they are the biggest flexible panels i could find in germany

and controllers are these:
VOTRONIC - MPP 165 Duo Dig.
because they are easily configured with a switch, there is a version which is at least a little bit waterproofed (you never know) and most importantly, there is a second output for the starter or aux bank so there is no need for a 2-bank ac-charger or a relay or anything. The second output is only 1A but that's totally fine to keep an unused bank fully charged all the time.

[StuM]

Originally Posted by SV THIRD DAY

My 320W string on a mppt controller has been averaging 78AH per day for the last 2 weeks.

Just had a thought. Is that all your panels could put out or is that all your system could accept because of your daytime house loads plus the acceptance rate of your batteries at their SOC?

At anchor in the afternoon, you would possibly be able to use/store a lot less than your panels were capable of putting out. (If your refrigeration etc is using 8 Amps and your batteries are only accepting 6 Amps, you will only be getting 14 Amps even if your panels are capable of generating over 20 Amps)

[GILow]

Originally Posted by txg

and controllers are these:
VOTRONIC - MPP 165 Duo Dig.
because they are easily configured with a switch, there is a version which is at least a little bit waterproofed (you never know) and most importantly, there is a second output for the starter or aux bank so there is no need for a 2-bank ac-charger or a relay or anything. The second output is only 1A but that's totally fine to keep an unused bank fully charged all the time.

Good to see someone else happy with their Votronic. I installed our Duo 420 a few years ago and it has not given any trouble. I cannot speak for its efficiency because I connected it to two VERY cheap and nasty temporary no-brand panels. And just as well I did because one was partially destroyed by flying debris in a storm less than a year after I installed it. So output now is pretty ordinary, I rarely see 200 watts from the pair of 140 watt panels. Before we set off cruising in three years I'll hook up some REAL panels.

P.S. I can't use the engine charging circuit on our Duo because our engine bank is 24 volts. But it is a good idea.

[john61ct]

Rather than (in addition to) quoting AH per day, which depends on too many outside variables, could people just give peak amps, as actually output from the controller?

[rom]

Originally Posted by john61ct

Rather than (in addition to) quoting AH per day, which depends on too many outside variables, could people just give peak amps, as actually output from the controller?

How would you then translate amps to watts ? As I suggested earlier we should just talk watts as this how a solar panels are rated.