New Home Construction and System help

[bave]

Hi everyone,

I looked and not sure where to start with this as a total newbie in this arena.

I am in middle TN and building a new home and considering a PV system. A friend of mine recently had a large system (~40 panels + 4 tesla powerwalls) installed and it was about 100k. Not looking to spend that much and not sure why it would cost that much from my reading but here are my thoughts.

I don't want to do a roof mount because of both aesthetics and paranoia about poking holes in my roof. I have plenty of room so I can do a ground mounted rack or ballast system. Would like a system that would largely power a 5k heated foot house and possibly an EV in an efficient manner. My electricity price is about .14/kwh. Home will have nat-gas dual fuel systems as primary heat with electric floor element heating in about 1k of the main floor area as well. Would like to have a battery system as well for backup.

So my questions....
1) Is it reasonable to be able to hire someone to do the work while procuring the bulk of your own equipment? Or will installers insist on providing the equipment so they can mark it up and make money on that side as well? Any particular method for finding reputable installers?

2) How far can the PV array be from the home without significant issues? Would like to have the array at least 200' from the back of the home.

3) Batteries. I see a lot of people using these ~$1300 rack mounted batteries. Why would anyone use a branded pre-built battery system like powerwall over those? The price difference seems huge.

4) Grid tie or no. TN has a pretty bad policy related to selling power back to the utility it seems. Looks like the TVA pays something like .03-.04/kwh for excess production which is why I would prefer to operate primarily on my own battery system to consume first and then supplement as needed from grid draw. How does that change the system design/hardware needs?

5) It is my understanding that the basic components of a system would be array > batteries > inverter > panel, is that about right?

Again, I apologize if this is redundant or misplaced. If there is a better source that explains all of this or someplace I can read more about it that would be helpful as well.

Thanks in advance.

 

[dougbert]

Hi everyone,

I looked and not sure where to start with this as a total newbie in this arena.

I am in middle TN and building a new home and considering a PV system. A friend of mine recently had a large system (~40 panels + 4 tesla powerwalls) installed and it was about 100k. Not looking to spend that much and not sure why it would cost that much from my reading but here are my thoughts.

I don't want to do a roof mount because of both aesthetics and paranoia about poking holes in my roof. I have plenty of room so I can do a ground mounted rack or ballast system. Would like a system that would largely power a 5k heated foot house and possibly an EV in an efficient manner. My electricity price is about .14/kwh. Home will have nat-gas dual fuel systems as primary heat with electric floor element heating in about 1k of the main floor area as well. Would like to have a battery system as well for backup.

welcome to the party, I will add what I know, others will hopefully do the same

I found that in retro fitting my 90 year old house, adding solar REQUIRES at least 2 main panels;

1) one for the grid input and grid only loads, including feeding the inverter
2) one for the critical loads that is powered by some sort of transfer switch on inputs: GRID or SOLAR

the transfer switch sits between the sources (GRID and SOLAR) and the critical loads panel

I wish I could have constructed NEW to build space for "THE POWER ROOM"


I prefer the ground mount option for the reasons above plus others, but I don't have land, wish I did then I could add LOTS more panels

watch this West Virgina couple who did off grid solar. They have 20 videos on their solar project

So my questions....
1) Is it reasonable to be able to hire someone to do the work while procuring the bulk of your own equipment? Or will instadon't lllers insist on providing the equipment so they can mark it up and make money on that side as well? Any particular method for finding reputable installers?

don't know that as I did my whole system DIY

2) How far can the PV array be from the home without significant issues? Would like to have the array at least 200' from the back of the home.

if you watch the above couple, their array was several hundred feet

3) Batteries. I see a lot of people using these ~$1300 rack mounted batteries. Why would anyone use a branded pre-built battery system like powerwall over those? The price difference seems huge.

yep, you understand

4) Grid tie or no. TN has a pretty bad policy related to selling power back to the utility it seems. Looks like the TVA pays something like .03-.04/kwh for excess production which is why I would prefer to operate primarily on my own battery system to consume first and then supplement as needed from grid draw. How does that change the system design/hardware needs?

I do not believe in Netmetering. It worked in the early days, but netmetering is going to be phased out eventually. Design your system without it

5) It is my understanding that the basic components of a system would be array > batteries > inverter > panel, is that about right?

yep

at the risk of TMI, here is my basic design diagram.

NOTE: My design had to work within the confinement of the existing house, physical layout and the grid service panel size
Today, I would have a 200 amp service if there is grid to be connected with.
If no grid, then it would be fun to design that......grin

Again, I apologize if this is redundant or misplaced. If there is a better source that explains all of this or someplace I can read more about it that would be helpful as well.

you will have more questions, I suggest you create a SHOW ME thread in the Show Me forum to document your project.
as questions arise, post them there and people who read it will come up with questions and you can have all the Q&As in one place

A link to my build is in my signature below

Thanks in advance.

welcome