# Any ideas for simulating my Ground mount with shade/sun?



## Meinecke (Jun 30, 2017)

Hello...

I am in the process of buying a property, but while i am waiting i want to simulate shading etc on the Panels, that i want to mount on Ground...
Will be Tracking system, similar to this at this link: https://cdn.instructables.com/FEP/253H/IVHQEG0L/FEP253HIVHQEG0L.MEDIUM.jpg
But i would like to create the system on paper first with knowing how to arange to limit shade etc...

Any ideas of an online or software based designer for such stuff??!

Thx in advance


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## Murby (May 24, 2016)

Solar panels do not do well in even a little shade.

Check this out:


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## Al Yaz (Jun 13, 2017)

The programs I have seen can be a bit pricey (for the good ones). Have you tried something like this: http://www.susdesign.com/tools.php

Also if you go online to ‘Home Power Magazine’ they should have an archive where you should be able to find what programs / apps they evaluated for solar / shading / location determination. I seem to remember an article on this some time back.

Some of us have to pick the best location - based on the most sun / least shade. Not all of us have complete access to a sunny array location. Good luck.


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## TraderBob (Oct 21, 2010)

Do you have a link to the instructable for the picture you posted? Thanks

"Will be Tracking system, similar to this at this link: https://cdn.instructables.com/FEP/253H/IVHQEG0L/FEP253HIVHQEG0L.MEDIUM.jpg"


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## Murby (May 24, 2016)

Meinecke said:


> Hello...
> 
> I am in the process of buying a property, but while i am waiting i want to simulate shading etc on the Panels, that i want to mount on Ground...
> Will be Tracking system, similar to this at this link: https://cdn.instructables.com/FEP/253H/IVHQEG0L/FEP253HIVHQEG0L.MEDIUM.jpg
> ...


I'd like to point out that the tracking system you linked to is not going to work. Even though the panels technically point left to right, the panels are spaced so closely together that the panels closest to the sun will shade those behind them.. Its a bad design. Someone didn't think it through. 

All of the panels need to move together on the same mounting platform so the array stays flat no matter which way its pointing.

I'd also like to point out that I don't think the array in the picture would survive a good windstorm.. it doesn't look rigid enough. 

Buffeting winds will vibrate an array apart..


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## Meinecke (Jun 30, 2017)

Hello and thx for the answer....i thought the same with the distance and mounting of this design...thats why i was wondering if it can be simple simulated...i mean the shading to see which distance it would take and if it is still usefull that far/close away from each other...
I was thinking of a triangle frame with two foundation posts on each holder (meaning front and back of the triangle each concreted to dirt) but the moving part was pretty pleasing...


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## Meinecke (Jun 30, 2017)

The link to the original project on instructables is here: https://www.instructables.com/id/52kW-Solar-Tracker-Controlled-by-Raspberry-Pi/


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## wy_white_wolf (Oct 14, 2004)

Do you just want to simulate the shading areas though out the day or calculate the lost output because of shade?


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## Meinecke (Jun 30, 2017)

No i want to see how much it would shade at all on some different given distances from each other to determine if it is even worth the planing...like when i need a full or even more panel size apart, than my 20 panels would take up to much space anyway and i could dump the idea...but it is just pleasing to have two panels above each other on a turning pipe and 10 of them next to each other on a triangle frame


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## Murby (May 24, 2016)

Meinecke said:


> No i want to see how much it would shade at all on some different given distances from each other to determine if it is even worth the planing...like when i need a full or even more panel size apart, than my 20 panels would take up to much space anyway and i could dump the idea...but it is just pleasing to have two panels above each other on a turning pipe and 10 of them next to each other on a triangle frame


That's just basic high school geometry.. Run your math at an hour after sunrise and an hour before sunset. I think you're going to find that you'll need to space the panels about 8 feet apart (edge to edge) for it to work.. That's why I said the photo of the system you linked to was a very bad design. 

If you want adjustable panels, you need to install a concrete base and embed a pole into the concrete..

This is what you want to build.. and this is the only thing you want to build.. Everything else is nothing more than backyard idiots without any engineering experience.



















These are single or dual axis tracking.. If you just want summer and winter adjustment, you can build a tilting array too.. they look more like conventional arrays like this:









And one other thing.. Stay away from anything made of wood. You need to use Galvanized, stainless, or aluminum and always use stainless hardware on everything.

Don't mess around trying to go "backyard cheap" because your system won't last but a few years that way. You'll put all that money and effort into it and in a few years, things will start to go wrong and your savings will evaporate.


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## wy_white_wolf (Oct 14, 2004)

Meinecke said:


> No i want to see how much it would shade at all on some different given distances from each other to determine if it is even worth the planing...like when i need a full or even more panel size apart, than my 20 panels would take up to much space anyway and i could dump the idea...but it is just pleasing to have two panels above each other on a turning pipe and 10 of them next to each other on a triangle frame


AutoCAD, Sketchup, or just about any 3d drafting/engineering program can do that. Sketchup was free last time I checked.

WWW


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## Meinecke (Jun 30, 2017)

Ok...i got you guys...
Don't do it is what i hear...
Looked at sketch up and for what i am trying to draw, it would probably take more time to draw in sketchup than building it from imagination with same accuracy.
I would need one of these easy cheesy tools, but than i probably dont get shade and so on...
And i definitely have not the patience to draw something from scratch when i have to draw every line of a beam.
So thx for the ideas and answers...
Will try to keep them in mind...


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## Skamp (Apr 26, 2014)

Sketch up does have a shading tool. It will take into account your latitude and you can adjust time of day and day of the year. 

I'd bet there are some models in the 3D wharehouse that you could use and simply assemble.


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## Murby (May 24, 2016)

If I were trying to do what you're doing and save money, I'd find a local scrap salvage yard and see if they have any 6 or 8 inch sch40 pipe laying around for scrap prices. You might be able to find a 12 footer for a couple hundred bucks.. You'd have to clean it up and provide a good corrosion coating, but it might be worth it. 

Expect to spend about $600 bucks for concrete too as you'll need to go down at least 6 feet...


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## Meinecke (Jun 30, 2017)

@Murby...
I really like your answers...but you are no fun when it comes to my DIY solar system...
Just kidding of course...
But it really looks like that i have to get my head around spending serious money for solar...hoped to stay way below 4 grant for everything...incl panels, permits, inverter and mount already...but i think you crushed that dream...


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## Murby (May 24, 2016)

Ya, I know what you mean.. With some projects like building a doghouse, a deer blind, a play set, or various other short term projects, going cheap isn't an issue.. But when you want something to last for time frames measured in decades, and that project is important to your infrastructure, it doesn't pay to go cheap.. In fact, just the opposite.. it pays to go the extra mile and over-engineer things.

For instance.. I'm putting in an 8KW solar system right now.. (pictures to come soon).. it puts out 25 amps @240 volts and has to run 150 feet back to the house. Now I could have gotten away with a 10 gauge wire and ~3.5% loss (voltage drop).... or gone with 8 gauge at around 2% loss.. or even gone to a 6ga wire at around 1.5% loss.. But I went with 4 gauge copper for a 0.9% loss and left myself open to expanding later on. If you do the math, you'll discover that the higher voltage drops add up fast over the course of a decade and the larger wire pays for itself.
After hunting around on Craigslist, I was able to find my 4ga wire, direct burial in copper, for about $150.. My cable actually contains 3 conductors (4ga) power conductors, 4 conductors (12ga) control (bonus!), and a 6ga ground and rated to use in just about any location including direct burial. That wire, with just the bare minimum 4ga-3conductors is around $5 a foot and yet I only paid $120 for the entire spool... 
But the real savings comes from the fact that I'll have only a 0.9% feed loss over the course of the next 25 years minimum.. and probably more like 50 years.. Plus I can add more power to the solar system and not worry about feed line problems.

Create a spreadsheet to manage all your costs... Include everything you can think of and then start on chewing them down.

One idea is to purchase an inverter but only half the solar panels.. (you'll have to consider shipping costs as they can be expensive for solar panels).. 

I actually started out the same way as you.. I just wanted a small system that could knock my $130/month electric bill down to something more reasonable.. I would have been happy with around $100 a month.. Then I started designing the system and laying out my expenses and I discovered it would take almost 10 years for it to pay for itself... OUCH! A ten year payback is a hard pill to swallow.. I started looking at my expenses and noticed that the size of the solar system was inconsequential to a lot of my expenses.. For instance, my permits for inspections and the utility interconnection were the same regardless if I put in a 2KW system or a 20KW system ($500 for permits).... Shipping costs for a 2KW system were only $20 cheaper than it would be for a 10KW system (from $360 to $380).. Connectors for the panels, oddly enough, were also the same.. I'd still have to purchase 30 foot of Unistrut and clamps to mount the inverter and junction boxes.. There were lots of costs that didn't change just because I went bigger.. so going bigger allowed me to spread those costs out.

What I ended up doing was creating a spreadsheet and recording the data from every electric bill for the past seven years.. We recorded monthly KWH used and the total bill and summed up the yearly costs as well as yearly power usage and also created averages..
What I discovered, as a side note, is that our electrical costs go up 1 penny per KWH per year.. In the last 7 years, its gone up 6 cents per KWH.. From 12 cents back in 2010, to a whopping 18 cents today.. And it will probably go up another penny per year for the foreseeable future.

Then I redesigned the system to provide 100 percent of our power requirements, added up all the expenses, and found out the larger system would pay for itself within ~5 years instead of almost 9 to 10 years.. You wouldn't believe how surprised I was when I discovered that...
My solar system is costing me about $1.10 per watt.. complete.. (that's after 30% tax rebates) it will pay for itself in 5.5 years..
As a bonus, I put a lot of the materials I had to purchase locally on my credit card which gives me points... as it worked out, I'm going to get about $250 bucks back in home depot gift cards just for using my credit card. (not included in calculations)

The key is to do all the work yourself and to shop around for the materials you have to purchase... Keep detailed records of your costs (Including shipping)
I bought all my solar equipment (panels, inverter, racking hardware) from a company called Renvu out in California.. We had some issues with shipping damage (not their fault) and some wrong parts received, and they handled it like champions.. The shipping company tried to screw me over and not pay my claim and Renvu put the proverbial screws to them... as it ended up, not only did I get the 5 damaged panels replaced free, I got to keep the original 5 damaged panels which are fully functional! LOL.. I actually ended up with an extra 1400 watts of free panels.. (also not included in calculations)

A solar system is an investment.. treat it like one and it will provide you with power for a long long time. In about a week, I'll be posting photos of my system during construction and the final product... We've taken pictures all along the construction process to document it all...

One other note.. Oversize your panel to inverter ratio by at least 1.25.. So if you get a 4kW inverter, make sure you get 5KW of solar panels.. 
I would forget the tracking system.. they're not worth the expense. (and yes, I did my homework on them) I went with an SMA transformer-less inverter and Solar World panels with a modified Ironridge ground mount.. The best of the best..

I highly recommend Renvu.. ask for Ian Farnsworth.. 

Here's a sneak preview of construction from a month ago... We're just getting all the framework aligned to pour concrete.. (we used 8 yards of concrete) The footings go down 6 feet.


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## Skamp (Apr 26, 2014)

I'm sorta impressed. Your homework is sound. How will you do on test day?


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## Murby (May 24, 2016)

Skamp said:


> I'm sorta impressed. Your homework is sound. How will you do on test day?


I don't understand what you're asking.. How will I do on test day?


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## Skamp (Apr 26, 2014)

Live it. And tell us how it is.


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## Meinecke (Jun 30, 2017)

@Murby...
Thx for this very well meant and complete explanantion...
And i would probablby did the same, if my budget would not be already depleted with purchasing the house...
So when i got my hands on the free stuff, i saw a silver stripe on the horizon to have some solar up years before i can build up enough funds...
You have to understand...i am German...and we dont do debt...meaning, i probably will not sleep well for the next 30 years becasue of having a house mortgage that i cannot pay off in one year...
So adding ANY dept on that is not an option...
But an Inverter here or there, some wood/metal for construction here and there and maybe a few little nick nacks as well...but def NO 10 grant...
But i will try to get stuff build as sturdy as possible...and my yunk yard around the corner is my best freind anyway and i love that place cause i can probably get everything i need for the project there...like walmart...smile...


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## Murby (May 24, 2016)

Ya, going into debt for something like this is not a good idea.. If you don't have the spare cash, I would certainly not recommend doing it.
That said, if you don't have the cash to do it right the first time, how will you get the cash to do it over again?

There are a few things to be concerned about.. The most nasty of them is that most utility meters are NOT bidirectional.. they don't care which way the current is flowing, they just add it to your bill.. That's a real stumbling block because without a permitted installation, the utility company won't install a bidirectional meter and you could end up generating free power for the utility company AND paying them for the free power you are giving them!

To my knowledge, no city inspectors or utility companies will permit a cheap Chinese inverter unless its passed the required UL certifications. 

There are certain ways to get around these obstacles but none of them are cheap. For instance, you could install a "Grid Interactive" inverter that pulls power from your battery bank first, then switches to pulling power from the grid when the batteries run low. Some of these inverters have what they call "Grid Zero" technology where they won't export anything but will allow you to draw from the grid. Again, they are expensive... really expensive.

There is another option that could limit your costs and allow you to grow later.. It will start out a bit expensive but be far cheaper later..
You could get a solar panel with a micro inverter..(about $300), set it up on a single pole (cheap), and get the required permit for the bidirectional meter.. You'll spend about $1000 and you'll only have a single panel installed so you won't get much energy from it.. But once you have that bidirectional meter installed, you can do whatever you want after that... Purchase more panels later and add them to the system as you see fit.

The cool thing about microinverters is that you can continuously grow the system and place the panels wherever you want.. a few panels on the roof, a few panels in the back yard.. a few panels on the chicken coop, etc... and they can all be tied back to your home's electrical system and you can add more whenever you want. 
Microinverters are more expensive but they do have advantages in that they turn each panel into its own MPPT channel.. this way, a single shaded panel won't bring down the others in the same string.. Another advantage is that when a microinverter goes bad, its just one inverter.. the rest keep going. The biggest drawback is they are more expensive.. as in more than twice the cost of going with a central string inverter.


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