Your thoughts on signature solar panels on sale.

[squarpeg]

I am buying stuff for an off-grid system. I am going to buy some batteries from signature solar and thinking maybe I would also buy some panels since shipping is a flat rate. There are so many panels out there, I am lost. The ones sale are generally costing about .48 a watt. Does that sound like a good deal? plus no additional shipping cost. Now my situation for the site. I am in Vermont, never gets hot here. We do get a lot of snow sometimes. These are being pole mounted. The site itself is not that great, slopes to the north. Neighbors tree line is going to give me a lot of ever changing shade. Not an issue for 6 months of the year but as the sun sinks it will be a problem so panels that do a better job in shade or diffused conditions, would be best. Already decided I am not going with micro inverters or super expensive panels so whether any of these listed are better choices than another I don't know, some claim to be decent dealing with shade. Can anyone offer thoughts on any of these??

Canadian Solar 400W Mono-crystalline Solar Panel (Black) | CS6R-400MS-HL

SEG Solar 405W Bifacial Solar Panel (Black) | Up to 526W with Bifacial Gain | PERC SIV Series | SEG-405-BMD-HV

Q.CELLS 395W Half-Cell Mono Solar Panel (Silver) | Q.PEAK DUO L-G5.2 395

Boviet 370W Bifacial Solar Panels (Black) | Up to 444W with Bifacial Gain | BVM6610-370-HC-BF

Thanks

 

[sunshine_eggo]

Shade just plain sucks. It will absolutely destroy PV performance. Micro inverters give you the best overall performance. Optimizers help, but cutting down your neighbors trees is the best solution.

Taking into consideration:

1. Northern latitude
2. Shading
3. Snow

• Half-cut bifacial panel is the best option.
• Keep series count as low as possible
• parallel as many strings as you can
• String panels according to the most favorable shading situation, i.e., better to have only one string completely shaded rather than a little shading on all strings.

 

[Supervstech]

Yeah... shade performance just doesn't happen with PV...
as said, the 1/2 cut panels are best for partial shade, parallel as much as possible in the pattern shade hits...

 

[Shimmy]

The 400W Canadian Solar panels are nice since they are "60-cell" format-- a little smaller than the 72 cell panels, esepecially if you are wanting to pole mount them. The downside is they are only 30Vmp, so you need a lot in series to get up to reasonable voltages. Not sure if they are better suited for microinverters vs a hybrid AIO system.

 

[squarpeg]

The 400W Canadian Solar panels are nice since they are "60-cell" format-- a little smaller than the 72 cell panels, esepecially if you are wanting to pole mount them. The downside is they are only 30Vmp, so you need a lot in series to get up to reasonable voltages. Not sure if they are better suited for microinverters vs a hybrid AIO system.

Just curious what you think is a reasonable voltage? Panels are about 150ft from house.

 

[Rocketman]

What voltage is your battery? 48v?
What solar charge controller or AIO are you using?
What are its specs for minimum charging voltage?

How many panels are you thinking of getting?

Then we can help figure out a reasonable voltage…

 

[squarpeg]

Battery 48v, I do not have the charge controller yet. I have a victron 5k multiplus so will probably go with appropriate victron controller. Thinking of about 4k in panels initially. Was thinking of 4 strings?

 

[BenFromSignatureSolar]

Battery 48v, I do not have the charge controller yet. I have a victron 5k multiplus so will probably go with appropriate victron controller. Thinking of about 4k in panels initially. Was thinking of 4 strings?

Check out the EG4 Charge Controller. Solid unit and can save you quite a bit that you can put towards modules.

How much battery backup are you looking to include in your system?

 

[squarpeg]

Check out the EG4 Charge Controller. Solid unit and can save you quite a bit that you can put towards modules.

How much battery backup are you looking to include in your system?

I will probably start with 2-3 of the EG4 lifepower4, ultimately I am thinking about 6 but out of reach for me at the moment.

 

[BenFromSignatureSolar]

Are you basing your battery backup on usage data? Are you trying to make it through the night on straight battery backup? Or is it more a safety net and your primary goal is to offset usage during the day?

 

[squarpeg]

Are you basing your battery backup on usage data? Are you trying to make it through the night on straight battery backup? Or is it more a safety net and your primary goal is to offset usage during the day?

I have no usage data at this point. This is an off grid situation. The batteries will be used as a straight backup. I do have a generator.

 

[Zwy]

Check out the EG4 Charge Controller. Solid unit and can save you quite a bit that you can put towards modules.

I finally finished install on the 2 EG4 SCC's. I purchased these with my own money and will be giving a review on the pair in the future.

I will say they do work.......... Actually one has been running since July 4th.

 

[Rocketman]

The good news for shading is if you are going with a Victron system you only need 5volts over the battery voltage to start - so 63v will cover it - which is 2s on probably any panel you will buy.

our friends in the sailboat will often put one Solar charge controller per battery- this way they get the maximum charge into the battery with all their shading issues - it’s worth it for them.

You will want to make a shade plan, so hopefully one string goes into shade while the other three are in sun, then another string goes into shade. You may even want more than four strings.

It will be a challenge to figure out the optimal setup, with costs (extra wires, and mppt’s), shade, and watts.

Get the BiFacial panels- pole mount and snow will help in the winter.

As you are running the wires to the panel area - you may want to run an extra set or two for future expansion or future smaller strings.

Good Luck

 

[Rocketman]

Also, if you are going with a Victron system - go all Victron- the data you get and history is AWESOME! That may become more important if you play with your string configurations in the future- because you can see what each mppt is producing or not producing.

Edit:sunshine is totally correct-except Victron batteries.

 

[sunshine_eggo]

Also, if you are going with a Victron system - go all Victron-

EXCEPT for Victron batteries...