Designing a new house around my current and future solar system

[terrango]

I am designing a new house around my current and future solar needs.
I am curious as to how many people here are running multiple inverters dedicated to different sections of their homes?

My original plan was to have 4-6 inverters powering different sections of my house.
But i am not sure if that is the best option. I do have access to grid power on my current property.
My thinking was i would use the grid as the "backup", and let the solar and batteries be the primary.
Or put some of the dedicated loads on Grid and the rest on solar.
Selling power back to my utility isn't the best option as they tend to screw you over.
I am perfectly fine wasting all the power i generate.

By the end of 2023 i will have 24kw of solar installed and about 1240 ah of battery capacity.
I am planning on expanding the solar to 40KW in 2024
I am also trying to plan for future electric vehicle needs.

Any advice would be great.

 

[John Frum]

1240 ah of battery capacity.

Is this a 48 volt nominal system?
What chemistry are the batteries?

 

[timselectric]

My system is designed with two separate systems.
10k for the important stuff. And a 30k for everything else.

 

[MichaelK]

Another option is to get inverters designed to be paralleled, and then instead of connecting different inverters to different sections of the house, parallel the output of all the inverters into one main panel. My Schneider XW is an example of one. So is Outback's Radian.

 

[x98myers7]

I (personally) would have multiple smaller systems that way each can be sized for use by season plus if you have equipment issues, you're not completely out of power.

for example; running 10amps continuous for forced air furnace in the winter requires a large array at a very different tilt angle compared to running A/C in the hot sun in the summer.

 

[John Frum]

My original plan was to have 4-6 inverters powering different sections of my house.

Why would you do this?

 

[terrango]

Is this a 48 volt nominal system?
What chemistry are the batteries?

It is a 48V battery system with LFP cells

On the topic of using multiple inverters for different areas of the house.....
My thought was some appliances are very power hungry like stove, AC, heating, so i thought maybe there was some benefit to a dedicated inverter to those loads.

 

[terrango]

My system is designed with two separate systems.
10k for the important stuff. And a 30k for everything else.

what inverters are you running for your separate systems currently if you wont mind me asking?

I have been looking at getting some EG4 units, but still not sold completely on them.

 

[John Frum]

On the topic of using multiple inverters for different areas of the house.....
My thought was some appliances are very power hungry like stove, AC, heating, so i thought maybe there was some benefit to a dedicated inverter to those loads.

Its not commonly done but It could work.
The wiring plant will be complicated.

 

[timselectric]

what inverters are you running for your separate systems currently if you wont mind me asking?

I have been looking at getting some EG4 units, but still not sold completely on them.

Growatt SPF-5000-ES in parallel.
Two for the important stuff. And six for everything else. Keeping everything the same for redundancy. In a SHTF situation. I only need two working units to get by on. Setting everything up for easy swapping.

 

[terrango]

Its not commonly done but It could work.
The wiring plant will be complicated.

Yeah the wiring would be fun lol.
I still have a bit of time to decide what to do for this new build.
Hoping some of the new inverters out there will work out all their kinks.
Maybe ill have to explore paralleling units.

Thanks for all the help guys!

 

[SparkyJJO]

I'd just parallel. Easier than a bunch of sub panels all over, and if you did have an inverter failure, the others could pick up the load only needing maybe some load shedding by you vs having part of the house dark.

 

[Shimmy]

Personally more than two independent systems is a waste of money.

For your stated size I would get two Sol-Ark 15k units in parallel, unless money is not an object in which case I would get three Schneider XW-Pro 6848's. A common bus gives you much more starting amps for motors.

Having a supplemental system for your most critical loads (usually fridge and network) can be nice, but might reduce your actual reliability if not done carefully.