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Would you bother with solar on this roof?

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Hi all. I'm closing on a home in the upstate region of SC and never imagined I'd buy a heavily wooded property. I actually never imagined leaving sunny Colorado, but I missed my chance to buy a dream home at a price I could afford. I'm posting this here instead of the residential subforum because I'm trying to keep the future setup isolated to my new garage and very small scale. Solar and battery stuff is a cherished hobby, so I'm not hyper focused on ROI, cost savings, or efficiency. I enjoy it, and am happy to pay for things I enjoy.

Regular loads:
Chest freezer (~150w running?)
Home networking and security (~150w with modem, router, security camera PC, and the PoE cameras)

Rare load:
1/3hp sump pump in crawl space (800w running, potentially a couple thousand surge watts - I haven't checked it out myself)

I don't imagine power outages are too frequent in this area as it isn't far off the beaten path, but knowing these items can continue to run if we get an overnight blackout would be nice - particularly the sump pump. I figure that an EG4 48v battery with an EG4 6.5kw all-in-one (recently reviewed by Will) would be good for this purpose and allow for some growth - and if I'm not mistaken could accomplish the goal without solar. But hey, I like tinkering with solar.

Roof faces directly south and does get direct sunlight at some point during the day, but I can't imagine it lasts long due to being surrounded by towering trees. So, would you bother with adding any solar here? If yes, any layout ideas? While I'm trying to have the setup in the garage, the panels would be better suited on the main roof of the home - more exposure.

I know shading will be an issue, so I'm thinking a group of panels on the right side of the roof and another on the left. If I understand the EG4 all-in-one correctly, there are two PV inputs and the manual references connecting separate strings, so I'm thinking that'd work. Maybe like 3 x ~400w panels in series per string.

Good times:
facing_south_sunny.png

Bad times:
facing_south_shaded.jpg

And the only other occasionally sunny place on the property - the planting area on the left:
back_sunny.png

From above (google earth slightly rotated, its more directly south)
house_lot.png

Seems like the peak of the south facing slant of the roof could be the best place. Something like this, 3 panels in series per string.
facing_south_sunny_panels.png


Thanks for any egging on
 
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If it's only a hobby, why not. If you are trying to get anything meaningful I'd be chopping down a section of trees for a ground mount system or buying a different house :D
Lol thanks for that, I don't want it to be a complete waste of effort though. I've never had to consider the effects of shading before and am unfamiliar with how extreme the effect really is. Like if I get ~2000w from a 2 x 1200w setup in peak sunshine, cool. If that window only lasts an hour and I get 100w from the system any other time, it's probably not worth it even for the hobby aspect.

I figure at 40% duty cycle on the chest freezer and the constant draw of the home networking stuff, that I'll be using 5kwh in a 24hr period. I'm excluding the sump pump here because there could be periods of time (drought or whatever) where it isn't in use. Covering that 5kwh sounds like enough enjoyment to warrant.

Given your user name, is there some mode on the EG4 all-in-one that lends itself well to the objective? I'd hate the waste the power coming in outside of the peak exposure window since 300w would more than run the freezer and network, but I don't know how these units prioritize charging source. It might work to only allow AC charging at night. Start the morning fully charged and block AC charging, run off solar even if there are periods where it's not sustaining the load, and then charge up again off AC at night or if battery hits a certain SOC at any point
 
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You'd have to over panel and have a larger battery that can cope with the high charging current.

If you are looking to cover outages only, a small generator would be more cost effective.
 
You'd have to over panel and have a larger battery that can cope with the high charging current.

If you are looking to cover outages only, a small generator would be more cost effective.
High charging current? Surely this is configurable? And unclear on the overpaneling recommendation unless it's to just keep the voltage of each PV input on the EG4 high enough (90v I think). I'm OK with the system charging from AC as needed.

Generator would be fine if I'm home but I don't want to dive in to a whole home generator or one with automatic starting if I can help it.. Would be cool to not sweat a 24 hour blackout if I'm out of town.
 
High charging current? Surely this is configurable? And unclear on the overpaneling recommendation unless it's to just keep the voltage of each PV input on the EG4 high enough (90v I think). I'm OK with the system charging from AC as needed.

Generator would be fine if I'm home but I don't want to dive in to a whole home generator or one with automatic starting if I can help it.. Would be cool to not sweat a 24 hour blackout if I'm out of town.
Yeah, it is configurable, but you are looking at an hour or two of sunlight. In that time you'd have to replace the amount you used.
 
I would at least be removing any trees which overhang the home's roofline*, and possibly remove or lop some others to the west, east and south to provide a longer unshaded window. Shade is thine solar enemy. It will cruel output.

If the shade is early and/or late in the day, that's not so big of an issue but if you are only getting a short window of unshaded panels then it will struggle.

* you just end up with gutters and downpipes clogged with leaves which results in inadequate drainage and water ingress damage.
 
Beautiful home and property

Do a loads calculation to determine how big a battery needed to cover them for 24 hours.

Then calculate how many PV watts are needed to generate that many kWh to recharge the battery during a 2-3 hour window when there is no shading by the trees.
 
SC is "southern Canada" or South Carolina? Yes, it would make a difference (angle of sun). I'd only do it if I was going to clear some trees....But that is me.
 
Beautiful home and property

Do a loads calculation to determine how big a battery needed to cover them for 24 hours.

Then calculate how many PV watts are needed to generate that many kWh to recharge the battery during a 2-3 hour window when there is no shading by the trees.
Hard to calculate with the sump pump, so removing that from the equation I'm calculating ~5kwh in a 24hr period for the chest freezer and networking/security stuff. Guess a lot of this hinges on how much unobstructed sun the roof will receive, and how damning the effects of shading are in the hours leading up to and following the full sun window.

Suppose I'll set up a security camera aiming at the roof and have it take a picture every 5 minutes or so, to see how long the full sun window lasts and how the shadows are cast on the roof before/after.

SC is "southern Canada" or South Carolina? Yes, it would make a difference (angle of sun). I'd only do it if I was going to clear some trees....But that is me.
South Carolina. Sadly the home is located near the property boundaries (road to the right/east, neighbors yard to the south - in my satellite pic) so clearing trees to expose more of the roof will compromise privacy. Quite a shame, I'd prefer modestly sized evergreens over the towering trees there now. Would give year round privacy and sound deadening, and the roof would be prime solar location.

I'll scratch my head about clearing some of the lot once I move in (the top left of my satellite pic). Would be a ton of work, but I wouldn't mind a nice half acre meadow area carved out. Only gotcha I can see is that the lot slopes down from the house in to the woods, so all the trees I wouldn't clear to the south are still towering + 30ft higher by default just from the terrain. If I did go through the trouble of clearing this area I'd probably revert to the original goal of a massive setup, but what a drag it'd be to find out it still wasn't enough and the clearing still gets heavy shading.

maybeclearhere.jpg
 
Unless you have a clear area already , Those trees around you provide a lot of cooling effect and wind damping in the winter .
They will provide more kw's of savings , those panels ever will and their free. A panel on the roof for a backup battery power would
charge up the backup in a week or so. I have seen people cut down the trees and their house bakes in the sun and use more kw's to AC it
than the amount of panels they put in . . Just my opinion , Try not to fc Mother Nature , She will get even and one step ahead.
 
Good times:
facing_south_sunny.png
How long does that last?
you are trying to get anything meaningful I'd be chopping down a section of trees for a ground mount
That’s wacked advice, man!

They need a 45’ tall observation tower with three times the proposed panel wattage mounted to it.
And at least twice the battery but I didn’t actually calculate it.

Actually I am partly to mostly serious about the tower. The old fire tower designs with a 10x10 platform on top have often crossed my mind as an expensive but not outrageously expensive solution to trees and terrain where neighboring owner’s trees are an issue. Plus it would be pretty cool lol
 
How long does that last?

That’s wacked advice, man!

They need a 45’ tall observation tower with three times the proposed panel wattage mounted to it.
And at least twice the battery but I didn’t actually calculate it.

Actually I am partly to mostly serious about the tower. The old fire tower designs with a 10x10 platform on top have often crossed my mind as an expensive but not outrageously expensive solution to trees and terrain where neighboring owner’s trees are an issue. Plus it would be pretty cool lol
I mean, if you are going to build a tower anyways for sure. But if not, think of all the live edge river tables you could make cutting down a 50' by 50' section of trees. You'd probably make a profit after you sold them all!
 
x100 on clearing some some trees to help. They would be too close for my comfort anyways due to storms and fires depending on location. If you must keep your trees, do a small scale proof of concept for fun.
 
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