# Bringing my new solar system on-line



## MichaelK! (Oct 22, 2010)

For several years, my meager 400 watt solar system supplied a bit of power at my cabin. But, a long-term goal of mine was to design and build a much larger system capable of powering my 240VAC well pump. This would reduce fuel consumption on the homestead significantly.

Using a clamp meter I determined that the 1.5hp pump was using 10 amps to run. This Fluke meter also has "in-rush" capability, and measured that starting amperage at 37-38 amps (500 mSec). That means I need a substantial inverter to supply that much power. I selected Schneider's XM6848 120/240VAC inverter you see on the wall here. It has up to 12kw of surge (60 seconds). I still have to plaster up and repaint the wall where the solar electronics got mounted. I ain't gonna leave it like that.









I coupled this to 15-300watt Renogy panels, wired three in series per array, a 3S5P configuration. The 115VDC from each array was funneled through a combiner box which feeds a Midnight 200 charge controller. The Midnight charges a bank of 8 L-16 batteries wired in series for 48V. Here's a pic of the array frame, made out of welded unistruts. 








The frame fits over a single steel pipe sunk in 48" of concrete, which allows the array to track the sun left and right. The horizontal stabilizers at the bottom also allow for season angle changes. I call it "Hillbilly solar tracking". Here are the arrays with the panels installed.







Though I did most of the wiring myself, my BIL is a retired electrician, so I had him inspect my work. I'll be sealing up the plastic conduit and getting it buried before winter comes.

Last month we flipped the breaker to start the well pump, and the XM powered it up with ease. I'm now in the performance qualification phase of the system. My rule of thumb is to run the pump only while the panels are capable of making >2400 watts of power. This happens after about 9:30 in the morning. If the arrays are swung over to face SE, the batteries are mostly charged by 9am. By noon though, there's enough excess power to bring the batteries up to float. I can continue pumping till about 3:30 in the afternoon if the arrays are swung SW. With the new solar power, I've gotten my 5000 gallon tank up on the hill completely full to the brim!

I have a video of the pump running, but that's too big a file to post here.


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## Steve_S (Feb 25, 2015)

I'm curious, how deep is your well and how many feet of line before the house ?


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## ForestToFarm (Feb 28, 2016)

So I assume you are pumping water into the 5000 gallon tank up on the hill and then it gravity feeds back to the cabin? Then you will be able to use water when there is no solar power production?

My uncle owned the side of a mountain. He had a well drilled on the hill above his house. Then he ran pipe down the hill to his house. It worked like a siphon and he didn't even need a pump.

A friend has a larger pressure tank in his well system, I think around 75 or 100 gallons. Enough water to get through most nights.

Terry


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## MichaelK! (Oct 22, 2010)

The well pump (1.5hp 3-wire 240VAC Grunfos) is positioned at -380 feet, though the static water level is -100 feet. At this depth, the pump produces about 5 gal/min. The tank is positioned at the top of the highest hill in the property, about 1000 feet away from the well-head, and about 150 vertical feet above the cabin. The water line running up the hill has a one-way valve at the well-head to prevent water in the tank from draining back into the well-bore. So, once power is off, water can flow downhill to the cabin, with about 75PSI of water pressure. About 90% of the water produced is used for irrigation. Here's a pic of my orchard, where the bulk of the water is going. I have about 120 trees in the ground.








The well used to be exposed to the weather, and had to be drained in the winter to prevent freeze damage. The structure you can see at the left edge of the third photo is the 12X12 building I constructed on top of the well-head. It's against the north side of the cabin, so it's in perpetual shade. Encapsulating the well-head means I can keep water available year-round now without the danger of the pipes freezing. It's also where the batteries and all the solar electronics are positioned. I constructed the roof of the building with a hatchway directly above the well-head for the future day when the well-pump dies and needs replacement.

The inverter output is hard-wired directly into the house panel and electricity use inside the cabin is as seamless as in any regular home. My wife has already run the toaster oven to bake "solar cookies" during peak sun hours. Now that the new system is wholely on-line, we can start shopping for a standard refrigerator, kitchen stove, and clothes washing machine.


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## ShannonR (Nov 28, 2012)

Will a system that size actually support an elec stove? How many amp hours in your battery bank?


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## Hitch (Oct 19, 2016)

That's awesome! If you don't mind me asking, what did you spend on your system? I'm assuming installing it yourself saved a boatload in labor costs.


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## MichaelK! (Oct 22, 2010)

ShannonR said:


> Will a system that size actually support an elec stove? How many amp hours in your battery bank?


 Possibly, though I think it would be foolish to try. A stove is just too many kilowatts to attempt to feed by solar. I still use gas for cooking, and I wouldn't even consider changing. The snippet about using the toaster oven was just a "can it work" kind of test. I'd never consider using it on a regular basis. Besides, the times of day you're most likely to be cooking, either morning, or evening is when solar resources are at their lowest. My L-16 have about 18kwh total, but assuming you should never go past 50% depletion, that works out to be 9kwh. 9kwh won't last long with an electric stove!


Hitch said:


> That's awesome! If you don't mind me asking, what did you spend on your system? I'm assuming installing it yourself saved a boatload in labor costs.


 Yes, I did everything myself, including all the cabin's wiring. The solar system totally was about 14K. About 4.5k for the Renogy solar cabin kit, 3.2k for the inverter (stole it), 3.2k for the batteries, about 1k for all the steel, another 1k for all the wiring, breakers, connectors, auger/tool rental ect.


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## ShannonR (Nov 28, 2012)

MichaelK! said:


> Possibly, though I think it would be foolish to try. A stove is just too many kilowatts to attempt to feed by solar. I still use gas for cooking, and I wouldn't even consider changing. The snippet about using the toaster oven was just a "can it work" kind of test. I'd never consider using it on a regular basis. Besides, the times of day you're most likely to be cooking, either morning, or evening is when solar resources are at their lowest. My L-16 have about 18kwh total, but assuming you should never go past 50% depletion, that works out to be 9kwh. 9kwh won't last long with an electric stove!
> Yes, I did everything myself, including all the cabin's wiring. The solar system totally was about 14K. About 4.5k for the Renogy solar cabin kit, 3.2k for the inverter (stole it), 3.2k for the batteries, about 1k for all the steel, another 1k for all the wiring, breakers, connectors, auger/tool rental ect.


Ok, I was just checking!! Some people get these ideas.... and don't understand solar. I figured you would have a pretty good idea of solar capabilities because you've been using it for awhile now. Glad you aren't going with an electric stove, methinks it would be the cause of a lotta extra hours on your generator lol


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## Murby (May 24, 2016)

I have my own grid tied system, yours is beautiful! Nice job!

I just installed my own 7.56 KW system that's been up an running for a couple months now and outperforming all my calculations. 

I looked at your inverter but decided to go with an Outback Radian 8048 so I could run a welder off of it if needed. I'm not even hooking it up.. its just sitting in a Faraday cage for safe keeping.. Since we have grid power, there's no point in using batteries.

You did a nice job.. congratulations.. its money well spent.


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## Meinecke (Jun 30, 2017)

What a great work...shows me again, that i really need an arc welder...


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## MichaelK! (Oct 22, 2010)

I used a little 120V Lincoln Electric welder and flux-core steel wire. Shielding gas isn't required with flux-core, so welding is easier. I did have to be very careful not the breath any of the fumes, because the unistruts were galvanized, and I didn't want to get zinc poisoning. Welding galvanized was also somewhat more problematic in the sense that you need a longer held arc to first boil off the zinc coating before you get down to the steel. Once you learn that, the welding when smoothly.


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## Meinecke (Jun 30, 2017)

Thx for the advice...but i am trained in welding...just since in the usa in lack of a good toy...


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