Solar on the Farm
Facts, Myths, Lessons, and Costs
Bottom Line: YES, I LOVE MY SOLAR AND WOULD DO IT AGAIN!
It seems like almost once a day, I get some blog on my Google news feed about solar and how wonderful it is. I usually end up screaming at my phone that most of what they have written is a lie! Then I take a step back and recognize that every place is different and maybe they just made a mistake when they said they were in northern Michigan and not Arizona. OK, I don’t usually do that. I spend a few minutes fuming about the lies that people tell on the internet for regurgitating an article for money. Then I move on. So for those that are interested, here is my experience with solar in the mountains of South-eastern Kentucky.
First, a few disclaimers:
· I did the entire installation myself. If you don’t have some confidence in construction, electricity, and safety, you are going to need a contractor. That is going to significantly increase cost.
· I was not particularly concerned about a long term Return on Investment (ROI).
· My primary goal was to be able to live well if something happened to the electrical grid, both short term and long term. We had a 9 day power outage due to an ice storm and even with my small generator, life sucked. Of course, now that we have the solar, the power has only gone out once in a year, and for only five hours! My neighbors should thank me!
· I tried to source all my equipment to avoid anything made in China. That is a hard one to do, and it will increase costs, but I try to avoid supporting the use of slave labor whenever I can.
· I haven’t done some of the things I should to decrease my household electric usage.
· My particular situation allowed me to do the installation, but some of the costs won’t apply if you choose a different set up.
· Your tax situation is going to be different than mine, so the saving you may get on your taxes will be different. You need to understand that before you sign a contract or start spending money.
OK, let’s dive in!
The System and Cost of Components:
· 15 KW of panels. 27 panels, rated at 540w each, with bi-facial production. These are sourced from India. They are bigger than the standard residential panels.
· Iron Ridge ground mount on 3 inch, schedule 80 steel pipes, with a concrete pad. I didn’t want to put the panels on my roof because I have a steep metal roof that is hard to walk on. Also, I get a fair amount of shade from the big trees around the house, so a ground mount made more sense, even if it raised my cost by about $8000.
o The pad is to help with the production on the back side of the panels.
o I got the pipe used for about a third of the cost.
· A 15KW Inverter that is hardened against EMP.
· A rack of LiFePO (Lithium Iron Phosphate) batteries that will store 32 KwH of electricity (about enough for 1 day’s usage without any other charge)
· The solar panels are 800 ft from the house, so I used 8 Ga wire for the run. That’s a little bigger than required, but I don’t have to worry about the wire overheating. I buried the wire in a trench 24 inches deep. I bought a used ditch witch, but renting one is easy. You don’t want to dig that trench without one.
Battery System | 10978.2 |
Racking System | 2597.29 |
Pipes | 1656 |
Wire | 2607.6 |
Solar Panels | 10093.06 |
Inverter | 10350 |
brackets | 138.21 |
Pipe and 2x4's | 589 |
2x4s | 87.45 |
cement | 3283.78 |
Float Rental | 39.16 |
MC4 Connectors and lugs | 108.43 |
Battery Wire | 338.35 |
Safety Switch | 428 |
busbar | 70 |
Comms Cable | 32.35 |
Conduit | 41.83 |
PV Wire | 267 |
Conduit | 40 |
Conduit | 165.65 |
My total cost was $43,911.
I had gotten a quote from an install company (they have gone out of business since then) that wanted $163,000 for a similar system.
The Build Process:
The most difficult part of the whole process was building the ground rack. If you are mounting on the roof, you can skip this part. I’m not comfortable walking on my metal roof, nor did I want to put a bunch of holes in it, but that is probably a good option for some people.
I bought all the rack hardware from Iron Ridge. They are well known in the industry and on homestead pages and have a good product. They have a design tool that for is online (and FREE) that does all the engineering for you. That includes wind shear and snow load. Wind is probably the biggest issue for a ground mounted system so it’s a good idea to over engineer your mount. You can make all the adjustments you want for angle, soil composition, height, etc. The program then gives you a drawing of exactly what you need to build. I had some problems with being able to dig deep enough holes for my vertical poles. So, I added extra structural supports, heavy duty wire anchors, and the cement pad. The pad also give you a nice reflective surface so that you get decent production from the back side of the panes if you buy bi-facial. Bi-facial also works well if you have grass growing underneath the panels. There have been some great results in big solar farms using sheep to keep the grass short. Grass actually reflects the right wavelength of light for solar panels better than even white gravel.
You have to source the steel pipes yourself. If you buy them new, you are going to pay about $7 a foot. Try to find them used. I got my pipes on FB marketplace for about $2 a foot. You can play with the engineering drawing to decide what size pipe to use. Smaller pipes mean more of them. I highly recommend doing bracing between the pipes. It doesn’t add that much cost and it makes things much more secure. I also bolted steel cable around the upper rack and bolted that to cinder blocks sunk into the cement pad. The last thing you want is for a good wind to catch your panels like a sail and lift it off the ground.
We decided on a whole house inverter, because our local power company can be spotty. If you choose to go with micro-inverters on the panels, you will not have electricity if the power goes out. You are basically using the power company as a battery. But if their lines go down, you don’t have any power. This is to protect the guys working the lines. Your panels are producing a lot of voltage which is feeding back to the grid. So when the power company goes dark and the linemen are out working, your system can’t be producing anything. This option is cheaper, but not something I would recommend. I had this setup in Hawaii, Nothing is more frustrating than having a power outage and looking at all your panels that aren’t doing anything. I wouldn’t put in a system without a battery. In fact, if you have to spend more money, put it into batteries.
The power company did want me to install a hard disconnect switch, but that was not hard at all. I didn’t have to get an electrical inspection because of where I live and my power company, but you may have to jump through those hoops too. Check with your power provider and city.
I was able to tie the inverter to the main panel of the house. This isn’t always possible and you should hire an electrician if you aren’t comfortable working with electricity. This is not something you want to learn as you go!
Money:
The tax breaks are nice, but only if you are paying taxes. Take a look at your tax bill from last year. Don’t just look at your refund. That is just the amount you overpaid to the government. Subtract your refund amount from the amount they took out. The difference is what you actually paid. I know for some of you, that last statement is obvious, but some people don’t know that. The tax credit is not refundable, so if you don’t owe taxes, you don’t get any money. You can carry the tax credit over to following years, so that may help.
The money you save on your electric bill varies a lot. For our setup, we ended up having a bill for six months last year. That’s mostly because our HVAC is old. We switched to all wood heat this winter and that kept our bill low for every month. It’s also very weather dependent. You still make electricity on cloudy days, but only about 20% of normal. So last November was terrible for us because of all the cloudy days, but that varies a lot. If you have a normal house and only get a small system, you are not going to replace all your usage. Most companies talk about a 8K system as a good size. That is only going to run your critical loads and will replace about half of a typical family’s usage.
The power company also charges a customer fee that you can’t escape. For Jackson Power, that’s $23 a month. A good month will bank about 250 KWh on the 15KW system. This will be different for everyone. We use a lot of power because of our business. Yours will probably be less.
So far, according to my monitoring app, I’ve gotten about a 6% ROI. So my system should be making me money in about 20 years. That would be better if I had gotten the tax breaks, but much, much worse if I had paid someone for the install.
I have the panels insured as a separate structure on my farm. If the panels are on the roof, you need to check with your insurance to make sure you are covered and it doesn’t void your insurance. You also have to make sure that your roof warranty isn’t voided by putting the panels on. Some companies will guarantee that, others won’t.
Production:
As I said, this varies a lot. Snow on the panels equals zero production. The panels do produce some heat, so even if it’s only 20 degrees, the snow will melt, but it takes a while. My panels are easy to clear with a big squeegee because they are ground mounted. If you have them on the roof, heating tape may be a good idea to melt the snow.
Cloudy days cut production to about 20%. Even a light haze cuts your output by about 50%. That can be a problem in the spring and fall here, so oversize the system if you can. If you are planning on needing power for longer than a day or two, a backup generator is a good idea. Even a small one, wired into the generator input of the inverter will charge the batteries enough in a couple of hours to last another day. I have a portable dual fuel generator that puts out 11,000W and it charges my batteries to 100% in about 90 minutes.
Choosing a company:
I really can’t speak to this since I only got one quote and almost threw up at the cost. The system that seemed reasonably priced was far too small. And the company was extremely shady, thus why they are no longer in business. I would research the heck out of any contractor. Don’t go with the first person that comes to the house.
Bottom Line:
Solar is a great thing to have and gives me a lot of peace of mind. I know I can make it through extended power outages. In fact, when we did lose power this year, I wasn’t even aware of it till I heard a neighbor’s generator going. Even if the apocalypse happens, I’m still going to have power. But it isn’t as wonderful as some of the articles make it out to be and it is expensive. A small system is going to be good for keeping the refrigerators running and the lights on. Electric heat, AC, or cooking is going to put a strain on a small system so plan accordingly. Get the biggest system you can afford.
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