How to pick solar panels?

[TechRider]

Hello Everyone,

I'm in the final stages of designing my solar system. I've got nearly everything picked out except for the panels. I have a basic idea what I want but I'm really struggling on making a decision. Here's what I have so far:
Inverter: Sol-Ark 15k
Storage: Custom EVE LF280 Battery packs (x4)
Racking: K2 Roof mount system on a brown metal roof.
There's also a lot of other little parts and pieces I've picked. I know I want somewhere around a 400W Panel and I'm going to try to fit as many on my roof as I can up to the limit of the 15k. I do have a little bit of shading to worry about from some trees that exists more through late fall - early spring. I live in NW Ohio so that time of year is pretty grey most of the time anyway. I've looked into optimizers as well and think they'd be a good idea. I like the idea of the Sol-Ark ones but if those are available in time, I was looking at the Tigos.

I've seen so many different kits and styles of cell out there, I'm not sure how to determine what is right for me. I think I like the idea of the half cell panels and the black ones seem to be whats in most of the "kits" I've seen. I've been leaning toward Q.Cell, I've read good things on here about them and have seen some good deals on Santan for them. I wouldn't say I'm doing a true budget build but I'm also not looking to break the bank.

So... How do I pick? Does black really matter in my area? Would I lose too much during the summer? I'm probably over thinking this, I have that habit.

Thanks!

 

[OffGridForGood]

Welcome to the DIY Solar Forum!

Inverter: Sol-Ark 15k
Storage: Custom EVE LF280 Battery packs (x4)
Racking: K2 Roof mount system

Not a buget system by any means, and you are planning a large PV set up it seems.
Panel selection: Used, or New.
Future matching - if you get Used now, will you be able to match them in the future if you expand the system?
All-black panels - generally an asthetic thing, however some have reported the panels will get hotter in the summer with black frames, and hotter=lower efficiency.
Search the forum - solar panel calculators are available to help you design the PV strings to suit your minimum cold temp and the MPPT inputs of your SolArk.
Roof top solar - means you need RSD (rapid shut down) and AFDD (arc fault detection & disconnect) these are supported by the SolArc, but need equipment like the Tigo's - to provide the disconnection function.
I have no experience with optimizers, someone else will be along to comment on these I expect.
Hope to see your post on the install when you get to that part.

 

[seneysolar]

Buy per pallet and youll find your best deal. Check A1 solar store, inxeption and signature.

Black is nice for appearance and melting frost at first light.

Think about your max voc of 500v and the voc of each panel.
Example: pallet quantity of 30. Panel voc of 41v figure 3 strings of 10 panels gets you 410v voc of each string.

Watts are going to be all over the place, you will want to balance watts with quality, physical size, and your budget.

Honestly voc planning is 80% of my decision making when buying panels. Too high and you end up with alot of strings, larger combiner box, more wires and so on. Qcell is a good reputable brand. My favorite is REC.

 

[chrisski]

I think Q-Cells are good, I have those on my roof. I do consider panels a commodity so it all goes with the jigsaw puzzle on the roof.

I also recommend doing some planning about how much those trees affect your output, and whether the trees need to come down or the project stopped. I plan on trees growing 1 - 2 feet per year. There are some apps that you can use your phone, stand at a location, and see what the output is at a given time of year.

I have two strings of PV for my Q-Cells, each set up 4S3P, which that voltage is good for my 300 volt MPPTs, and could be good for shading. The more parallel strings on the roof, the better for shading.

 

[Spunky]

Here's your Panel Calculator .
And some near by used panels listed here on the Forum's for sale page.

I'm located 4-5hrs north of you in Michigan and have panels that have about 40 volts (VOC) each.
My strings were limited to 8 (panels in series), you may find that to be true also after checking the calculator.
Sounds like a nice solid system design

 

[HarryN]

I grew up in that area, so I understand your concerns. The sun is not all that bright even when it is sunny compared to for instance Albuquerque, NM.

For many locations, there is a substantial cost difference in grid electricity for time of use, and there can also be higher rates assigned depending on your "max peak power draw" that month. My father had a business that was subject to this even 50 years ago.

If I were putting up a system in that area, I would strongly consider to use poly panels instead of mono to enhance the gathering of scattered light, low intensity, and somewhat red shifted spectrum of sunlight in that area.

I would also try to face the panels so that they are gathering light as late in the day as possible so that they are producing power during the maximum price vs max total production. This will be more like ~ 4 or 5 pm in August vs the traditional ~ 1 pm. The panels could end up being more or less vertical vs roof top.

It is worth considering the idea of tapping into wind vs solar in NW OH if you have room.

 

[TechRider]

First, thanks for all the replies!!

My property is bordered on 3 sides by trees, then our front lawn (south facing) has a bunch of mature maples. I'm living in the house I grew up in so I saw them when they were planted. There are a few dead branches than I know I can thin out. From when I've started checking it's about the lower 1/3 of the roof that gets the most shade and that's Feb/March time frame.

I'm leaving the Generator portion of the 15k open so I could think about doing AC coupled Wind maybe. It sure is windy today and seems to be a lot lately. I haven't really looked into it much however.

I'm looking to get new panels by the pallet. I wasn't sure if it was more important to pick features first then go with a panel that matched the right specs? This is probably the main area that I'm stuck. A friend of mine has bifacials and I'm pretty sure those wouldn't be good. I spec out hardware for a living for my job so I'm used to the task but there seems to be a lot of competing info and a lot of, this is better for this region, vs that type of info. I'm almost moving fast (probably a little too fast) and haven't given the panels their due research time like I have the other aspects. Partly because of the sheer number of manufactures and the fact they did seem to be more of a commodity.

I think my roof is going to be the limiting factor and I'm going to need to look for a smaller higher watt panel (don't we all want perfection.) I tend to lean towards a, figure out the features and pick something that matches, mindset. I'm not sure if that's helping or hurting in this case.

A couple years ago I was quote a turn-key $72k install with enphase and no battery. They had the panels spec'd "landscape" on the roof. I'm going to try to do "portrait" to saving a little on racking costs.

Here's my house and all the trees, the house is east-west lengthwise:


My plan is to get the bulk of the panels in the middle section of the roof. Then on each of the triangle ends, try to fit 4 or 5 panels and run those in series together. I thought about doing some E-W facing panels to get some of the early morning and later evening but I'm not sure it's worth it.

 

[TechRider]

Oh, I forgot to address the RDS item. Both the optimizers I'm looking at have RSD built in. That's part of the reason I'm looking at adding them.

 

[TechRider]

Well, I decided to just rip the bandaid off. I did some quick measurements and the panels I've been watching at Santan fit my roof nicely in 3 rows so I ordered them today! Model: Q.PEAK DUO BLK-G6+ 340W

 

[SeaGal]

I've got nearly everything picked out except for the panels...
... I do have a little bit of shading to worry about from some trees that exists more through late fall - early spring.

So you've already chosen between Stihl and Husqvarna?

 

[Hedges]

Two problem trees...how should I cut them down?

Two problem trees...how should I cut them down?

forestryforum.com

"I can show you how to put a shaped charge on the bottom tree. That's the most fun way to drop them. I've blown stumps out with properly placed charges before. Other than the slight danger of setting the charge, there is very little danger, the work is being done with you a ways away.


I cut it twice and it's still too short"

 

[TechRider]

That looks like a TON of fun!!! :D