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diy solar

Moving off grid to Tennessee

Chgobeartrader

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Joined
Nov 14, 2021
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Hello new member here. My Family and I are building a home in Tennessee. I'm looking for help in designing and or Installing a solar system, that will give us the same usage we have now. Computers, refrigerator, tv's, all your basic needs!
Thanks in advance, Joe
 
Where you at, Joe ? I'm halfway between Nashville and Clarksville TN.
Building a 10kw off-grid system myself
 
Where you at, Joe ? I'm halfway between Nashville and Clarksville TN.
Building a 10kw off-grid system myself
Hello, we are in Chicago, IL. Now but moving to Hohenwald, TN. Next year. I will probably need a 10kw off grid system myself. How far long are you building your system? Thank you for replying sorry took a bit getting back. Found you sitting in my spam.
 
Where you at, Joe ? I'm halfway between Nashville and Clarksville TN.
Building a 10kw off-grid system myself
Hello guys,

I'm also in middle TN, specifically in Murfreesboro, and I'm also seeking to build a power solution for an outbuilding/shop that currently has no power. This building is approximately 350ft away making it pretty pricey to just run a simple 60A/240v panel out there.....wire alone will likely cost me somewhere near $2500 with the cost of copper these days, then pvc conduit and renting out a trencher etc... it's gonna add up and I'm not sure I wanna make that investment here since we may be selling in just 2-3 yrs. Trying to figure out the cost of a solar array to handle my needs out there which aren't really that much, mostly need power for lighting, a table/miter saw on occasion, an air compressor when needed, etc.... not even positive I need 240v but it'd be nice to have should I need to run my welder, 60gal air compressor and 14" bandsaw.....but if not cost-effective I'll have my 9500W genny on standby that I could use for the 240v. Again much of these tools would be on occasion. I'd say mostly lighting, a fan or two and a power tool would be the more consistent power consumption.

I'm not well versed with this kinda power source but just going by genny wattages, I'm thinking all I need is roughly 6k-7.5k of power for this building....I don't plan on running anything other than 2 outdoor LED lights and maybe a wall-mounted exhaust fan through the night. Am I way off my numbers, how are you guys figuring out your needs???
 
FB911:

You need to narrow down you "wants" or "maybe" list. If you want solar to cover the loads, things like your air compressor are going to make a LOT of difference in the equation. They have very high start up current requirements. If you plan to move in 2 years, that is going to make a difference too.

Start by making a list of all the items you would have, and then go online and check out their energy usage. Or better yet, get a Kill A Watt meter for $30, and plug it in with stuff and actually measure your loads where ever possible. Or get a hand held unit with a clamp meter.

You could put in a modest system, and supplement it with your generator for when you need sporadic loads.

Good luck!
 
FB911:

You need to narrow down you "wants" or "maybe" list. If you want solar to cover the loads, things like your air compressor are going to make a LOT of difference in the equation. They have very high start up current requirements. If you plan to move in 2 years, that is going to make a difference too.

Start by making a list of all the items you would have, and then go online and check out their energy usage. Or better yet, get a Kill A Watt meter for $30, and plug it in with stuff and actually measure your loads where ever possible. Or get a hand held unit with a clamp meter.

You could put in a modest system, and supplement it with your generator for when you need sporadic loads.

Good luck!
You make a very good point.... 95% of the time you just need a kw or two, but the other 5% can have a lot higher power requirements. Very much worth considering the stragegy, esp if your generator runs on diesel.
 
Hello guys,

I'm also in middle TN, specifically in Murfreesboro, and I'm also seeking to build a power solution for an outbuilding/shop that currently has no power. This building is approximately 350ft away making it pretty pricey to just run a simple 60A/240v panel out there.....wire alone will likely cost me somewhere near $2500 with the cost of copper these days, then pvc conduit and renting out a trencher etc... it's gonna add up and I'm not sure I wanna make that investment here since we may be selling in just 2-3 yrs. Trying to figure out the cost of a solar array to handle my needs out there which aren't really that much, mostly need power for lighting, a table/miter saw on occasion, an air compressor when needed, etc.... not even positive I need 240v but it'd be nice to have should I need to run my welder, 60gal air compressor and 14" bandsaw.....but if not cost-effective I'll have my 9500W genny on standby that I could use for the 240v. Again much of these tools would be on occasion. I'd say mostly lighting, a fan or two and a power tool would be the more consistent power consumption.

I'm not well versed with this kinda power source but just going by genny wattages, I'm thinking all I need is roughly 6k-7.5k of power for this building....I don't plan on running anything other than 2 outdoor LED lights and maybe a wall-mounted exhaust fan through the night. Am I way off my numbers, how are you guys figuring out your needs???
Lot of high draw items on that list. IMO, it's going to be a whole lot cheaper to simply use your existing generator, or run aluminum triplex to the shop.
 
You could do a very basic system 2000/3003 watt inverter charger with 4 golf cart batterys and a 1200 watts of solar
then just run the generator for big equipment you large generator could charge your battery’s and run tools at the same time , and a few solar panels can keep up with charging with small tool and keep up the charge Daly
 
Hello guys,

I'm also in middle TN, specifically in Murfreesboro, and I'm also seeking to build a power solution for an outbuilding/shop that currently has no power. This building is approximately 350ft away making it pretty pricey to just run a simple 60A/240v panel out there.....wire alone will likely cost me somewhere near $2500 with the cost of copper these days, then pvc conduit and renting out a trencher etc... it's gonna add up and I'm not sure I wanna make that investment here since we may be selling in just 2-3 yrs. Trying to figure out the cost of a solar array to handle my needs out there which aren't really that much, mostly need power for lighting, a table/miter saw on occasion, an air compressor when needed, etc.... not even positive I need 240v but it'd be nice to have should I need to run my welder, 60gal air compressor and 14" bandsaw.....but if not cost-effective I'll have my 9500W genny on standby that I could use for the 240v. Again much of these tools would be on occasion. I'd say mostly lighting, a fan or two and a power tool would be the more consistent power consumption.

I'm not well versed with this kinda power source but just going by genny wattages, I'm thinking all I need is roughly 6k-7.5k of power for this building....I don't plan on running anything other than 2 outdoor LED lights and maybe a wall-mounted exhaust fan through the night. Am I way off my numbers, how are you guys figuring out your needs???
You need a really good inverter to run a big air compressor. I'm looking at 3 inverters : the Outback 8048 radian, the MPP Solar LVX6048WP and Midnite Solar's new Rosie 6048.
I would need two of each to run my house; you can get by with one.
All of these have good surge capacity but the MPP Solar is probably the weakest.
Sounds like Wellbuilt's solution would be the most economical.
 
Yeah, I know this is a solar forum and all that, but with all the heavy need; welder, air compressor, saws, etc., and after adding enough panels/batteries/chargers/inverters/and of course cables, to handle those needs, I'd wager FB911 is going to be a in a lot less $ to simply run the 350' in triplex, or better yet, simply use his 9k generator when power is needed. If the op simply wants a few lights and occasional hand tool use and goes with a small solar system, well, even that is going to take a big bite of that $2.5k to run triplex.
YMMV
 
Well, I'll start the default answer to these questions and we can work from there. Here's you To-Do list:

1: Power audit! This will give you some important information on how big your inverter needs to be as well as how much battery capacity you'll need. There is a link in the FAQ section (I think, or someone here will post it shortly) so fill in the blanks and see what it comes up with. You'll probably need some sort of Kill-A-Watt to get accurate measurements. Are you going to be running a 12v system? 24v system? 48v system? What are the specs on your solar panels? VoC? Vmp?

1a: Where do you live? Speccing out a system for Scotland is a LOT different numbers than Arizona due to the amount of light you actually get. Someone here can post the link to the Uber-Sun-Hours calculator site to help figure out how much you'll have to work with. That will be a box in the Power Audit form.

2: Parts list: You don't need a make & model list, just a parts list to start from for reference. You'll need an inverter, a MPPT charge controller, fuses, shunt, buck converter, batteries, wire, etc. Once you have a basic list it can be fine tuned to make & models after that.

3: Budget!: Steak is great but doesn't mean anything if your wallet says hamburger. :) Figure out what you're able to spend now vs what you'll have to cheap out on now and upgrade later. Availability out there is also going to be a major hurdle so figure out what your options are for suppliers.

4: Tape measure! Figure out where you're going to stick all the stuff you'll need. A dozen 3000AH batteries sounds great until you're sleeping on the floor because there's no room left for a bed. Is there a shed or closet or space that can house all this stuff? Will the server rack batteries fit? Are you going to have to make space? Physics can be pretty unforgiving.

5: Pencil out what you think you need and throw it at us so we can tell you what you've missed (because we ALL miss stuff the first go-round :) ) and help figure out which parts and pieces you're going to want to get.

A basic list of what you're going to need is:
AIO Unit, the Growatt
Batteries
Wire and crimps based on the amperage load you'll be drawing from the batteries
Fuses for the batteries
Combiner box depending on how many panel strings you're planning on using now or in the future
Bus bars to connect all the wiring together
Shunt to keep an eye on the system
Panels
Mounting for said panels

The power audit will help point you at the size of the fuses you're going to need for the batteries and the panel strings will determine what size fuses you need for the combiner box. Fortunately you can pretty much figure those out last.

I don't know if you've been running on a generator or are starting from scratch, but this just gets you a source. If you want to plug in appliances and such you're still going to need to figure out the AC side of things like breaker panels, breakers, wire, outlets, boxes, etc.
 
I power my cabin with a out back flex power one system a 3600watt /48v inverter charger
flex max 80 charge controler and 4500 watts of solar I don’t make heat with the system
heat is wood for no and everything is propane .
I can use a small compressor , chop saws table saw really any thing I want .
I used the system to build the house . It works good .9A9DBF95-944A-4C23-AFA3-943DAAD3D16B.jpeg
 
I power my cabin with a out back flex power one system a 3600watt /48v inverter charger
flex max 80 charge controler and 4500 watts of solar I don’t make heat with the system
heat is wood for no and everything is propane .
I can use a small compressor , chop saws table saw really any thing I want .
I used the system to build the house . It works good .View attachment 74663
Beautiful ... cabin.
 
Holy moly it took forever to find this site again, after upgrading my PC last winter.....TY for all the replies!!!

As you can see, I wasn't in any rush and had a few other projects going on but I am VERY interested in working out some numbers for comparison sakes. I already know it'd very likely be cheaper to run the line but curious how much cheaper, if only 10-20% cheaper, I might go for the solar option cuz I could at least take that with me when I leave.

So I've ordered a watt meter from Amazon to help figure out the power consumption of some of the items I'll want to run most. I failed to mention in my first post that I'd like to be able to run a multi-bank battery maintainer for several items (ie. motorcycle, zero-turn mower, tractor, etc..) along with any outdoor led light probably on a timer or photocell. Other than that, I'd only need more power for when I'm working on something in there which won't be every day/night. I'm thinking Wellbuilt's recommendation is right on point. I don't know what I was thinking when I mentioned needing 6k+ system.

Thanks again guys!
 
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Holy moly it took forever to find this site again, after upgrading my PC last winter.....TY for all the replies!!!

As you can see, I wasn't in any rush and had a few other projects going on but I am VERY interested in working out some numbers for comparison sakes. I already know it'd very likely be cheaper to run the line but curious how much cheaper, if only 10-20% cheaper, I might go for the solar option cuz I could at least take that with me when I leave.

So I've ordered a watt meter from Amazon to help figure out the power consumption of some of the items I'll want to run most. I failed to mention in my first post that I'd like to be able to run a multi-bank battery maintainer for several items (ie. motorcycle, zero-turn mower, tractor, etc..) along with any outdoor led light probably on a timer or photocell. Other than that, I'd only need more power for when I'm working on something in there which won't be every day/night. I'm thinking Wellbuilt's recommendation is right on point. I don't know what I was thinking when I mentioned needing 6k+ system.

Thanks again guys!
Since we last visited this post, you can buy a 16 channel whole house power meter for $130 from amazon. I forget the name, but you simply install the CTs that are included on each of the breakers in your house and assign them a channel like "dryer" "water heater" "bedroom". If your panel box has more than 16 breakers, you can combine the wires from different breakers by feeding more that one wire thru a given CT. For example you can combine the breakers for two bedrooms into one CT. If they are on opposite phases, you simple run one wire thru one way and the other the opposite way. If they are on the same phase (leg) you run the wires thru the same direction. I did this from my whole house system by combining the inside air duct unit and my outside heatpump unit into one CT. That way my HVAC system shows up as ONE channel on my power meter despite actually using two breakers.

Tips for reducing peak power. Peaks are always the problem in an off grid system. What happens when you are cooking and the heatpump and water heater come on at the same time? How often does that happen? Can you do some sort of load management system when the water heater can't run if the stove is on? I bypassed the load management by getting better equipment. Last year we replaced the 5ton heat pump and a 3.5ton ducted minisplit. The air handler was a one for one swap and it still uses my existing ductwork. The minisplit pulls 800w where the 5 ton heatpump on first stage used to pull 20kw start and 3.5kw running. This year we replaced the LP hotwater heater that had failed with a heat pump water heater. It pulls 360w when running as compared to 4500w for a normal water heater. So I just reduced my peak power appliances of 8kw with 1.1kw. So now I don't have to worry about load management at all.

One more tip about the water heater... the heat pump water heater comes with standard heating elements as a backup and they pull 4500watts. So I ordered 1500w elements from amazon. So in the future when the heat pump part of my water heater dies, I'll still only pull 1500w and won't need load management.

One more tip about the water heater.. if you slip the Lowe's employee a $20, he can dent the thing with the fork lift and you can get it for a significant discount.


Hope this helps. Understanding your power usage before you buy can save you a lot of money. Or just create a 12kw inverter system and don't think about it. lol.
 
For the past year I’ve been doing a dry run solar test for a move to Tennessee in the area surrounding Chattanooga, below the bluffs in the valley or around the lake. Presently I’m in the Sacramento Ca area. The test system are twin LV6548’s, 32kwh of batteries and only 4400 watts of P.V. Just something to get a grasp of reality, not just numbers. The house load is primarily a cloths dryer, air conditioning, refrigerator, microwave, dishwasher, coffee maker, tv and lighting , the usual stuff. If the furnace and water heater weren’t gas, there would definitely be another wrench in the works. During the spring and fall the system is self sustainable with little to no grid support. My biggest take away/surprise at this point is how much solar you actually need. I probably need 3 times what I have to be independent for heat waves and probably much more than that if I was to heat electrically. And this is sunny California! Low sun angles, obstructions and a week of cloud cover are things that I really didn’t have a total understanding of, but now I think I’ve got a clue.
 
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