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Eg4-18KPV - Troy goes on a new adventure

tmprof

New Member
Joined
Jun 9, 2021
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69
Location
Humble, Texas
I'll try to keep this short and to the point :) Total Newbie, never had solar anything on my house. I live in Houston Texas, new(er) neighborhood with very short trees, nothing blocking roof. I am an avid DIY and do a lot of carpentry work (I've shingled a few houses..etc) I also have dabbled in some electrical (added a 240 sub breaker box for a hot tub). I want to install solar myself without hiring some turnkey solution.
So on to the details:

My average kWh per day is around 60 (even with the 105+ temps!) and my 30 day usage is 1.712kwh
30_day_power.jpg


This will be a grid tie system, but I am not planning on net metering in the beginning. I want to start small and start with just inverter and battery backup. After I feel comfortable with that, I'll purchase solar panels locally and install them at a later date.
For the inverter, I want to start with the EG4 18Kpv + the 30kWh Lithium Powerwall. I understand that this will probably not be enough to power my house and I'll add a 2nd full rack later. So here are my beginner questions!

1. Permits....what will I need to just install the grid tie + battery backup? My thoughts is that I'll get the inverter installed on the wall and hire an electrician to move the lines from the meter to the inverter and then back to my existing breaker box (which is 100A). I keep hearing about online wizards that can step you through the permit process, but I haven't found a link (I don't mind hiring someone to do the permitting either if it's reasonable). Does anyone know of someone in the Houston Area I could contact?

2. Does the 18KPV need optimizers or micro inverters for the panels? I can get Canadian solar 385-400 watt mono panels locally. I was planning on getting 4 to start with and install them above my hot tub. That way I can get comfortable with the mounting setup and wiring back to the inverter.

That's it for now. I'm sure I'm missing some very obvious things but I appreciate any help you can provide.

-Troy
 
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Ok, it seems I found the answer to my 2nd question if optimizer or micro inverters are necessary:
You don't need anything between your solar and the 18kPV's MPPTs to work, just as long as your PV strings are series'd to a high enough voltage to start the MPPT. Depending on where your panels are mounted, you may need MLPEs for 690.12 compliance but that's where the transmitter can help make things plug and play if compatible.
 
You may need Rapid Shut Down modules on the solar panels, its an NEC requirement.
If you are not planning on Net Metering then your system doesn't need to be a grid interactive type of inverter it could be an Off-Grid type which costs less.
The downside of an Off-Grid inverter is that the transition between utility pass thru/charging and Inverting is not necessarily seamless.
 
You may need Rapid Shut Down modules on the solar panels, its an NEC requirement.

Absolutely! When I install the Solar I will add the external shutdown module(s). Based on current reviews, I'm pretty set on the 18KPV. It will give me room to grow in the future as I continue to add.

Being not connected to the grid does not mean you can ignore current building codes.

I would definitely want to follow current building codes! Ok, I found THIS that talks about ESS (which I now know means "Big Battery") I just read through it and I'm not sure what will not meet the requirements. Can you explain further? The only thing I see is the spacing between batteries maybe?
 
It is not possible in a single post to provide all the code information needed. UL9540 is a requirement a battery married to a inverter have been verified to meet the requirements by a recognized testing center. NEC2020 contains in a subset the specifics of required practices which includes things like limitations on maximum storage allowed and where, plus all the electrical.

ESS is energy storage system and has nothing to do with any single vendor ( Big Battery is not what I would use for batteries and nothing they sell is UL9540 listed ), you can search for UL9540 on this forum or internet and that should give you plenty to read, and this doesn't even touch the solar part or the mechanical needs for the racking which usually will required UL listed components as well as a full panel permit package stamped by a PE ( professional engineer licensed in your state ).

One can build systems like the large one you are thinking about, many here have including me, but you need the skills of many trades, building codes, NEC codes to do it correctly and meet permit application requirements.

The internet is full of people willing to sell you parts and / or saying "anyone" can do it yourself solar, they just want to sell equipment or get higher Google rankings. This is a good forum with many knowledgeable members. When you get to the part of ask specific questions, I'm sure you will get good feedback, but must be much more specific in nature.
 
The inverter and battery system I am planning to buy is 9540 listed :
https://signaturesolar.com/eg4-18kpv-hybrid-inverter-system-bundle-30-72kwh-eg4-lithium-powerwall/

I was just joking with the big battery comment and wasn't specifying a particular brand.

The specific question I really need direction on is which permit do I focus on first and any resources to aid in filling it out. This first step does not include me installing any solar panels.

Thanks again for your patience and help.
-Troy
 
The inverter and battery system I am planning to buy is 9540 listed :
https://signaturesolar.com/eg4-18kpv-hybrid-inverter-system-bundle-30-72kwh-eg4-lithium-powerwall/

I was just joking with the big battery comment and wasn't specifying a particular brand.

The specific question I really need direction on is which permit do I focus on first and any resources to aid in filling it out. This first step does not include me installing any solar panels.

Thanks again for your patience and help.
-Troy
Don't forget to shop around spending that kind of money.
 
The specific question I really need direction on is which permit do I focus on first and any resources to aid in filling it out. This first step does not include me installing any solar panels.
That ultimately will always be a question for your AHJ, not a random collection of people spread around the world haha.
There is a lot of advice to be had from this forum, some of it is great and some of it is total rubbish.
I think we are seeing a split between genuine DIY don't give a damn about regulations and professional to the book installs.
 
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