Logistics for a big system

[Dagoof]

First time poster. Thanks for your patience.

I've got a house in the country in Idaho. We use lots of power because I water two acres with a well and have nothing but electricity for heat. Fortunately, I have a big shop (100'x40' metal quonset hut) near my house, and I'm planning to mount my array on it with about 60 panels and four inverters.

Just getting started with design, but my question is about where what goes where.

Since my shop is a bit removed (250' or so) from the breaker panel on the far side of my house, I'm trying to understand what should go in the shop and what should go in the house. My understanding is that I don't want to send DC power that far, so the inverters should go inside the shop. Does that mean that I'll be sending four sets of AC wires to the house breaker panel for grid tie?

Also, I plan to add battery backup but not till later. Can the battery backup go in the house near the panel grid tie? Or will it need to go in the shop near my inverters?

 

[Dagoof]

 

[Dagoof]

Also, this may be a long shot, but is there any way to feed power back through my shop subpanel? Or will I for sure have to tear up the yard to run a new line from the shop back to the house?

 

[Dagoof]

 

[Sebanavila]

Check out this guy, he did something similar at what you want, but off-grid:

https://youtube.com/channel/UCMgHp0p8yXqtUEKSiukQ_jQ

 

[Dagoof]

Check out this guy, he did something similar at what you want, but off-grid:

https://youtube.com/channel/UCMgHp0p8yXqtUEKSiukQ_jQ

Thanks.

At first glance, it looks like he ran DC power all the way back to his electrical room.

 

[toms]

If the AC wiring from your workshop to your house is a suitable size to carry your household current you can use it.

 

[12VoltInstalls]

If the AC wiring from your workshop to your house is a suitable size to carry your household current you can use it.

there any way to feed power back through my shop subpanel?

What size is the breaker(s) in the main panel in the house? And what size is the subpanel feed wire? I’m assuming the shop is also split phase?

Does that mean that I'll be sending four sets of AC wires to the house breaker panel for grid tie?

So you’ll be feeding the grid? If so there’s gonna need to be a transfer switch at the house to disconnect if grid-down occurs. Usually the heavy equipment handles that and it’s located adjacent to the entrance.

Also, I plan to add battery backup but not till later. Can the battery backup go in the house near the panel grid tie?

My understanding is that I don't want to send DC power that far,

You answered your own question. Remote batteries are also DC. So, no.

With that many panels, achieving high DC voltage and sending it to the house where all the equipment would be located is probably where you’re going to wind up

 

[Northernchateau]

In my area if your going to Grid Tie your panels you need to have the electric company come out and do a site survey 1st.
At that time I would inquire about the electric code.

 

[Dagoof]

In my area if your going to Grid Tie your panels you need to have the electric company come out and do a site survey 1st.
At that time I would inquire about the electric code.

Thanks

 

[Dagoof]

What size is the breaker(s) in the main panel in the house? And what size is the subpanel feed wire? I’m assuming the shop is also split phase?

So you’ll be feeding the grid? If so there’s gonna need to be a transfer switch at the house to disconnect if grid-down occurs. Usually the heavy equipment handles that and it’s located adjacent to the entrance.


You answered your own question. Remote batteries are also DC. So, no.

With that many panels, achieving high DC voltage and sending it to the house where all the equipment would be located is probably where you’re going to wind up

My house panel is 200 amp. In it I have a 60 amp breaker that feeds the shop through 1 guage wire I think.

I'll be feeding the grid with a net meter at the house, but not sure if I should put the inverters there or in the shop.

Battery backup isn't going to happen until sometime in the future, and I could put them in either spot. (house or shop)

 

[12VoltInstalls]

So the 60A line could be inadequate
I’d put everything at the entrance, use high voltage from the panels to mitigate losses.

 

[peakbagger]

Standard non commercial arrays can put out in the 400 to 500 volt range. Amps are lower AC or DC for a given wattages at higher voltages. Therefore the wire size will be smaller if you move DC long distances than AC.

If you do grid tie you need to contact the utility to confirm what their break point is between small arrays interconnection and large array interconnection. They have to give you permission to interconnect and most states require the utility to do a "short form" abreviated interonnection application for minimal time and dollars. Once a system is sized to go over that limit then its a standard interconnection process and that can literally take years and significant dollars. I have one client that was told it was minimum of two years before they can an interconnect as there are too many projects in that area.