how was parallel solar done before microinverters

[cdoublejj--]

AH-HA!! minimum voltage and best range!

Guys i've seen multiple multiple people say that, i think people are running OG setups. Solar is up against FUD and ignorance. EDIT: one guy in here mentioned a regional thing though.

As far as missouri goes, being under some trees, it sounds like a parallel STRINGS are the way to go? with by pass diodes and or optimizer.

 

[sunshine_eggo]

AH-HA!! minimum voltage and best range!

Guys i've seen multiple multiple people say that, i think people are running OG setups. Solar is up against FUD and ignorance. EDIT: one guy in here mentioned a regional thing though.

As far as missouri goes, being under some trees, it sounds like a parallel STRINGS are the way to go? with by pass diodes and or optimizer.

Remove trees. Shade will destroy production under all circumstances

 

[wattmatters]

Remove trees.

Or place the array in a largely unshaded position instead.

 

[ksmithaz1]

I'm not sure what you have been reading but there is a reason the power company runs at extremely high voltage in high tension wires. Also a reason why telephones used 48vdc (53 nom) instead of 12 or so, which is the same reason 'POE' is 48v not 12, and . . . A reason motors and power supplies are more efficient at 240v than 120v. A reason EV battery packs have moved from 120 to 200 to 400 and now to 800v. And it's all the same reason. The lower the voltage the greater the negative impact of the resistance of your conductors. EE101. I would like to see the DC battery feeds go from 48v to 96, or even higher. Dead dc cells in batteries and panels can cause issues but modern designs mitigate the bulk of those. Running 1000mcm cable at $30/ft is a waste of resource, and difficult to work with. Whenever feasable, push up voltage instead of current.

That being said. . . I'd probably not series more than 10 panels. I'd look at it from a perspective of having to take a string offline to replace a bad panel vs having debris blocking production. For example say you were going to have 18 panels . . . 6x3 for 3 strings of 6 still gives you 67% of your production in the event you have a problem with one of the strings. I myself would never run strings in parallel one mppt per string, protects from parallel voltage variance issues. The other huge issue with massively parallel is a short or other high drain will take the whole thing down. Which is why mag-lites hold a dozen D batteries in series (okay 4 then).

Last note: Its the amps that kill you not the volts. A tesla coil generates extreme voltages, and will light a florescent tube thru your body without you even feeling it. Impractical because you can't keep the electrons on the wire at that pressure, but you should get the idea.

 

[upnorthandpersonal]

Last note: Its the amps that kill you not the volts.

It's neither the volts nor the amps on their own. It's the combination of both (i.e. power). You need to overcome the impedance of the body with enough voltage, and once you do you need to get enough current flowing. Impedance, not resistance since the body equivalent schematic is a combination of pure resistors and capacitors (which incidentally is the reason AC is more dangerous at lower voltages and low frequency than DC).

 

[ksmithaz1]

It's neither the volts nor the amps on their own. It's the combination of both (i.e. power). You need to overcome the impedance of the body with enough voltage, and once you do you need to get enough current flowing. Impedance, not resistance since the body equivalent schematic is a combination of pure resistors and capacitors (which incidentally is the reason AC is more dangerous at lower voltages and low frequency than DC).

Maybe I should have said it's the amps that cook you. You can stop a persons heart with a small battery. Higher voltages at lower current is generally preferable, though there are many factors. OTOH High voltage and current like in an EV battery is a double whammy. Panels are also DC, which to your point can be worse at higher voltages despite what Edison might think. The fatter the wire you have to deal with the harder it is to make a mechanically secure connection.

 

[sunshine_eggo]

Maybe I should have said it's the amps that cook you. You can stop a persons heart with a small battery. Higher voltages at lower current is generally preferable, though there are many factors. OTOH High voltage and current like in an EV battery is a double whammy. Panels are also DC, which to your point can be worse at higher voltages despite what Edison might think. The fatter the wire you have to deal with the harder it is to make a mechanically secure connection.

Are you using ChatGPT to generate answers? Most of what you say is nonsense-adjacent.

 

[Sean Very North]

Are you using ChatGPT to generate answers? Most of what you say is nonsense-adjacent.

I've a feeling the ChatGPT generated responses would make much more sense.

 

[cdoublejj--]

Remove trees. Shade will destroy production under all circumstances

Or place the array in a largely unshaded position instead.

thats not really an option around these parts, we can trim them up good that's about it. it's been an issue with star link.

i WAS hopping that with an ass ton of panels and good chunk of them being 400ish watt panels i'd be able to get a decent output to put a good dent in the power bill. it's two building with one piggy back of the main so i was hoping at worst the piggy back could also have a solarr array and battery bank as well. the main building isn't used very much. just a TV and lights, occasion air compressor usage. mosto fthe power usage at the piggey backed building.

 

[wattmatters]

thats not really an option around these parts, we can trim them up good that's about it. it's been an issue with star link.

You collect the photons you can in such circumstances. Smaller strings in parallel, or microinverters can help a bit. But there's no getting away from the fact shade kills production no matter what you put up.

I have a row of trees which hurts production in the Winter half of the year. I have them lopped annually to reduce the impact. We am permitted to cut them down if we wanted but they look nice and the aesthetic also has value to us, so I accept it costs us production.

I also have outbuildings (two) serviced via sub-boards from the primary dwelling supply.

Plenty of people here installed Starlink thinking it would be their internet saviour (often due to an irrational hatred of the national broadband service), only to realise afterwards that their trees meant poor reliability of signal and worse service than what they replaced.

 

[Rednecktek]

Plenty of people here installed Starlink thinking it would be their internet saviour (often due to an irrational hatred of the national broadband service), only to realise afterwards that their trees meant poor reliability of signal and worse service than what they replaced.

Well when your other options are 9Mbit DSL or Hughs Net... Starlink looks really, REALLY good.

 

[cdoublejj--]

You collect the photons you can in such circumstances. Smaller strings in parallel, or microinverters can help a bit. But there's no getting away from the fact shade kills production no matter what you put up.

I have a row of trees which hurts production in the Winter half of the year. I have them lopped annually to reduce the impact. We am permitted to cut them down if we wanted but they look nice and the aesthetic also has value to us, so I accept it costs us production.

I also have outbuildings (two) serviced via sub-boards from the primary dwelling supply.

Plenty of people here installed Starlink thinking it would be their internet saviour (often due to an irrational hatred of the national broadband service), only to realise afterwards that their trees meant poor reliability of signal and worse service than what they replaced.

so are you saying, i might be on to something here? if install 4000+ watts of panels i can maybe expect 950 watts? i could maybe live with that, sounds like it might be an experiment? sounds like heavy pruning might help.

what counts as a smaller string?

 

[Supervstech]

so are you saying, i might be on to something here? if install 4000+ watts of panels i can maybe expect 950 watts? i could maybe live with that, sounds like it might be an experiment? sounds like heavy pruning might help.

what counts as a smaller string?

It isn't just that...
The panels will only produce when they are not shaded...
So, let's say you have a surrounding of trees, and you have good sun after 12, and it's gone by 2
Your 4000W of panels could produce say 12kWh of power, then nothing...

Trees cut accumulated power... which is kWh's
Watts are an instant reading of output potential.
It's the hours that count.

 

[wattmatters]

The panels will only produce when they are not shaded...

In daylight there will still be production, just at significantly reduced output compared with the no shade condition.

The one time production is less affected (relative to the unshaded scenario) is on cloudy days. The daylight is more diffuse and what normally casts shadows has much less effect. For a PV array which tends to suffer shading through much of the day (e.g. due to tree branches/leaves) then they will probably find production is quite a bit more on cloudy days than on sunny days.

 

[cdoublejj--]

thats what i'm asking but, you both gave opposite answers. i was asking if i get 10 400 watt panels can i get even 25 watts of power from them. Supervstech said they will make no power at all. watt matters, said they will make a little power.

i was thinking i might get at least a few watts and peak power for the strings that are getting full light. thats also why i WAS thinking full balls to the wall parallel but, i still need to read up on by pass diodes.

 

[Supervstech]

thats what i'm asking but, you both gave opposite answers. i was asking if i get 10 400 watt panels can i get even 25 watts of power from them. Supervstech said they will make no power at all. watt matters, said they will make a little power.

i was thinking i might get at least a few watts and peak power for the strings that are getting full light. thats also why i WAS thinking full balls to the wall parallel but, i still need to read up on by pass diodes.

Oh, if there is sunlight out, ambient light will put out some voltage, and some wattage… if it exceeds the charge controllers minimum voltage, it may send some watts to the system, but what should be 4000W will be very little indeed…
My 375 watt panel is shaded all summer… in winter without leaves on the trees, it produces around 250W, in summer it is fully shaded most of the time… I am lucky to get 10 watts from it.
So, you’d likely get 100 watts or so from ambient light.

 

[rhino]

I don't know what the correct terminology is but there are also panels out that are "split" such that either the bottom or top half can be completely shaded and you'd still get 50% of the rated power instead of near 0% for regular panels. The Q.PEAK DUO XL-G10/BFG is example of one but that is bi-facial. I'm sure there are non-bi-facial panels that have same feature.

 

[sunshine_eggo]

I don't know what the correct terminology is but there are also panels out that are "split" such that either the bottom or top half can be completely shaded and you'd still get 50% of the rated power instead of near 0% for regular panels. The Q.PEAK DUO XL-G10/BFG is example of one but that is bi-facial. I'm sure there are non-bi-facial panels that have same feature.

"Split cell" or "half cut"

 

[cdoublejj--]

is that anything current connected or signature solar sell? maybe between that and trimming the trees and doing both sides of the roof and maybe stand some up on the back side maybe i'll get enough to top the batteries off. it sounds kind of like a lost cause on one hand. but, the on the other i'm still looking at getting a rack of batteries and an EG5 18k for power outages, i like it better than a whole home genny, where you have to run them and maintenance and have fuel. i also think newer gennys are sub par quality and designed to fail because they often charge and arm and leg for the inverter boards.

and the whole home units from generac and what not don't look much better (i get chinesesium vibes). then again i guess i could play around with where i put the panels too i guess?

anyone made a carport roof out of solar panels?


EDIT: also anyone seen those face book ads for those cheap 150ish watt solar panels that weigh 75 lbs each that are consist of silicon tubes and are ten year old new old stock?