diy solar

diy solar

super NEWBIE - wanting to conquer the solar world with a new off grid install.

macmedia

New Member
Joined
Apr 27, 2024
Messages
4
Location
Goshen NY
Howdy. I'm a new member and beyond Newbie in solar knowledge.
I've been procrastinating for years but quickly getting cash-strapped because of my inability to move ahead with a mega project (off grid) that I have been slowly planning.

My background: I have a 10,000 sq ft house with accessory buildings in the NY Metro area. It's been getting exceedingly unaffordable for the utilities last couple of years - especially with my elderly parents that moved in and keeping the heat pump mini splits at 85 degrees and higher. I have 400 amp service coming into the house and my usage can be from 4000-9000 kWh each month and even more.

My equipment: I bought 5 years ago 220 solar panels (265w each Canadian Solar) with Enphase m215 micro inverters. They have been sitting around gathering lots of dust waiting for me to figure out how to install. I bought this from a guy that advised me but I didn't learn too much at the time.

My needs: I'm not a dumb person (well maybe I am..) but I'm going through this somewhat blindly and looking for guidance and even perhaps someone who does this for as an advanced hobby or even as a business. It's one thing to build my own rack to mount the panels but it's a whole complicated story when I'm thinking I will need to go off grid (or at least partially) with a large battery array and what I really need to plan for. I even thought about buying 1 or two EV's (crashed) for doing a homemade Powerwall.

I have done a whole ton of research but I think I am running in circles. I'm not really sure I know what I'm thinking is correct. I have spoken to a few solar professionals locally but not one of them is interested in getting involved since I did not purchase the equipment from them. I reached out to NYS NYSERDA for assistance but the people they referred to are in the business of selling equipment and not operating as consultants.

Anyone that knows where I can turn to discuss and help with planning? Obviously this is NOT a simple system and I know I will have to compensate for help.
 
220? As in Two Hundred and Twenty solar panels that are 265W each?
Just want to make sure thats not a typo
 
With the size of the system you would need (4000 to 9000kWh per month is a lot, the average household in the US has monthly usage of 1300kWh) and the complexity of permitting in a Metro area for grid tie or even Off grid you really do need a professional company.

To be honest with you I do not think it would pencil out as an affordable thing to do. Sadly the panels you bought, even if unused will have lost a lot of value since new panels are selling for very little.
 
Obstacles:

Do you have real estate for doing this size of ground mount?

With this amount of power consumption you are going to be stacking large inverters, do you have a dedicated utility room /building for this?

Return of investment, do you have a budget? $100k? $150K$ Plus a large generator if truly going off grid.

Does local zoning allow off grid? Metro area typically do not. Likely you will be in a grid tie scenario.

Battery storage for this kind of useage will be a challenge to be useful.

If you are cash strapped now, my suggestion would be start reducing consumption. Reduce the square footage that you are trying to climate control. If needed, upgrade appliances to save energy. Reducing consumption saves thousands when building an off grid system. In your case id say tens of thousands.
 
Offgrid or ongrid?
Your panels and microinverters, if M215 puts out 215W, would deliver 47kW, 197A.

Is net metering available? If so, on-grid is the way to go. However, it is likely M215 doesn't have the newer features required for permission to connect.

To have 200A of backfeed in a 400A panel, you would need to either reduce main breaker to 200A, or have no more than 200A of load breakers. Same difference.

Assuming you have to or want to change inverters, 58kW of panels is about right for 40kW to 50kW of inverters. If panels are oriented half toward morning sun and half toward afternoon, peak out put is lower so about 30kW of inverters would fully utilize them most of the time.

2x hybrids like SolArk, EG4 18kPV, Midnight The One could be one option. They can support net metering, grid backup, or off-grid.

For purely off grid, some others are attractive like multiple Midnight Rosie + Barcelona (may support grid as well at some point), Sunny Island + Sunny Boy (what I use), Schneider + their SCC.

What are your electric rates?
Hardware for GT PV will cost $0.025/kWh amortized over 20 years. Turnkey installed, $0.10/kWh.
Batteries will cost $0.05/kWh (or more) amortized over their 16 year, 6000 cycle life.
 
220? As in Two Hundred and Twenty solar panels that are 265W each?
Just want to make sure thats not a typo
No - I'm not lying. Here's a sad photo - my panels were tarped but over the years it blew away and boxing came apart. I said 220 but I think I actually got 225.. The pool in the background will be rebuilt and the roof put back on there. The area is 40x100ft which is big enough to have all of the panels mounted to it.
 

Attachments

  • unnamed-6.jpg
    unnamed-6.jpg
    497.2 KB · Views: 9
  • unnamed-5.jpg
    unnamed-5.jpg
    703.1 KB · Views: 9
Examine MC4 connectors for corrosion before assembling.
They are in the weather, and some may have ended up in puddles. I got some panels with connectors cut off and found water wicked into the wires and corroded to some depth.

Lately we've been buying panels for $0.17 to $0.30/W. At $0.25/W you have about $15k worth.
You'll need mounting hardware including clamps or bolts, typically 4 per panel on 2 rails, sometimes 6 on 3 rails.
In other words, newer panels in the 400W range would cost half as much for clamps. I've been trying to buy up enough for my project on eBay, leftovers for a cheaper price.

If you want to ground mount, that at least won't require RSD electronics per panel (about $50 each, so $10k savings).
I used Unirac ULA. Others here use Iron Ridge. There are also poly tubs to be filled with gravel simply placed on the ground.

Whatever you put in you will be living with for decades, so plan something you'll be happy with. Maybe a large shade structure with usable space underneath. Roof you mentioned, over pool? You're right, 4000sf should fit the panels (flat) with about 25% area to spare. They can probably be given a reasonable tilt without shading each other much of the time. Landscape orientation may use more mounting rail but should allow some production even when each row shades the next (due to orientation of diode-bypassed PV cells strings in the panel.)

If you're up for DIY (including directing hired labor) and you get the necessary insurance to protect yourself as employer, you can assemble something quite cost effectively.

Otherwise, a turn-key complete system install with vendor providing all material is likely the way to go. Which means selling off the panels. Generally, you won't be able to find a legitimate contractor to build a system with your materials.
 
Offgrid or ongrid?
Your panels and microinverters, if M215 puts out 215W, would deliver 47kW, 197A.

Is net metering available? If so, on-grid is the way to go. However, it is likely M215 doesn't have the newer features required for permission to connect.

To have 200A of backfeed in a 400A panel, you would need to either reduce main breaker to 200A, or have no more than 200A of load breakers. Same difference.

Assuming you have to or want to change inverters, 58kW of panels is about right for 40kW to 50kW of inverters. If panels are oriented half toward morning sun and half toward afternoon, peak out put is lower so about 30kW of inverters would fully utilize them most of the time.

2x hybrids like SolArk, EG4 18kPV, Midnight The One could be one option. They can support net metering, grid backup, or off-grid.

For purely off grid, some others are attractive like multiple Midnight Rosie + Barcelona (may support grid as well at some point), Sunny Island + Sunny Boy (what I use), Schneider + their SCC.

What are your electric rates?
Hardware for GT PV will cost $0.025/kWh amortized over 20 years. Turnkey installed, $0.10/kWh.
Batteries will cost $0.05/kWh (or more) amortized over their 16 year, 6000 cycle life.
Thank you for the detailed info. We thought that with the panels it would be enough for my usage but it has steadily increased. I have 1 main 400a panel (single phase) and 10 sub panels. I can put the solar on one new panel and have some of the other panels hook up to it to keep it to 200a (like all my 40 mini splits systems and other high drawing items). My rates are 7-11 cents kWh for electric and another 12 cents for delivery. Welcome to NY.. Net metering is available but I saw the packet one year and nearly gave me a heart attack with the amount of information to fill out.
 
Obstacles:

Do you have real estate for doing this size of ground mount?

With this amount of power consumption you are going to be stacking large inverters, do you have a dedicated utility room /building for this?

Return of investment, do you have a budget? $100k? $150K$ Plus a large generator if truly going off grid.

Does local zoning allow off grid? Metro area typically do not. Likely you will be in a grid tie scenario.

Battery storage for this kind of useage will be a challenge to be useful.

If you are cash strapped now, my suggestion would be start reducing consumption. Reduce the square footage that you are trying to climate control. If needed, upgrade appliances to save energy. Reducing consumption saves thousands when building an off grid system. In your case id say tens of thousands.
I have 14 acres - plenty of space and permitting should not be difficult. I have plenty of space for a utility room or building. I'm spending north of $25-$30k a year in utilities so I hope that I can find a renewable solution - spend a little more now to get rid of that crazy power bill for years to come. I can't reduce consumption - in fact, I expect to use even more. Eventually I will open my place as a B&B so all spaces need to be conditioned well and no cold spots as I have now.
 
No - I'm not lying. Here's a sad photo - my panels were tarped but over the years it blew away and boxing came apart. I said 220 but I think I actually got 225.. The pool in the background will be rebuilt and the roof put back on there. The area is 40x100ft which is big enough to have all of the panels mounted to it.
Sad indeed!

Watts are watts, even if they are old, so start with getting them mounted. Thats a big project in itself and DIY friendly if using a system that has previous engineering approval. Its also the most labor intensive and likely reason for an electrician to say no...

I dont think your current micro inverters will do what youre asking and i dont think you'll have enough of a surplus to worry about sell back. Your goal should be to reduce the monthly cost.

That being said, Id look at the Solark 15k (probably quantity 4) you can stack up to 12 if you ever need to. In my opinion they seem to be the best bang for the buck when doing grid tie.

Tip: You may want to make friends with the local electrician at least for final hookup. I have found that inspectors are more comfortable with contractors they know vs homeowners doing it themselves, they dont "dig" until they find something.
 
My rates are 7-11 cents kWh for electric and another 12 cents for delivery. Welcome to NY.. Net metering is available but I saw the packet one year and nearly gave me a heart attack with the amount of information to fill out.

You pay $0.19 to $0.23/kWh.

If you do 100% DIY labor yourself, including building batteries from individual cells or buying cheapest off-brand, a PV, battery, inverter system might cost $0.05/kWh. More reasonable is closer to $0.10/kWh. Turnkey, best you might do is $0.15 but most I think will cost more. And those prices are amortized over 16 to 20 years, ignore interest/time value of money.

I think you should get the B&B going, have revenue, with a plan to put up solar later maybe.

If B&B is in the distant future regardless and you want to spend time on this, look into net metering first. Batteries won't store summer production for winter heating, but net metering can.
 
Sorry, I am prone to writing novels.

Everyone has an opinion and many are different. If I was in your position I would hire out the design. There are companies that will do it for a fee. There are a few on here that will do it as well. Your system is large but can be broken into many small chunks.

But, here is my take on it. You can spend 3 to 6 months reading on here and learning more about solar, and you should do that. But, hiring a licensed electrical engineer and getting stamped plans should give you a good design, equipment list, and you will know that what you are going after will be functional, to code, and reliable if done correctly.

This will probably cost you a few thousand and will take the engineer a while. They will need to start with an accurate design of your current electrical system which is why you need someone local. Then they will do the 1 line drawing of the solar install and probably several more detailed drawings of the different sub systems. Batteries, solar panels, MPPT, inverters, contactors, breakers, fuses, wire sizes, etc.

You can absolutly learn to do all this yourself and you will have a very good feel for what is right and wrong. Mostly it is to do with how much time you have before you want a working system.

And whatever way you choose to go, do submit all the designs here before buying anything else. Buying equipment before you have a design is a bad way to do things and will end up costing you money in the end.

I have been planning my system for 6 months and I am still learning new and better ways to do things.

Do buy quality tools. Stick to Temco, klein, greenlee, and other professional quality tools verse buying the cheep stuff amazon.

For multimeters, you need a clamp meter preferably one that catches peak/surge amps ( a good brand is fluke for this). It will be more expensive than the cheap ones, but is worth it.
A watt meter sometimes called a solar test meter, this will let you test all those panels you have before mounting them to ensure they are not faulty And the connections are good.
A 4 wire micro ohm meter is nice for checking battery impedance and cable/connection resistance.
A nice to have or even required is an infrared camera to see hot spots, this can be a an attachment to a phone or stand alone unit.

And don't bother with a starter system to learn on. Use 48v from the get go since you will end up there. A small system the size a typical house uses or just to run one of your many subpanels on is good.

Buy some reference books like this one. There are other titles that work but it is nice to have a reference.

That is the way I would do things.
 
Last edited:
Back
Top