off-grid electrical system for cabin

OP
timberland
Joined
Apr 8, 2014
Messages
558
The OP never mentions what he’ll be using in the cabin that draws voltage.

I have a 100w solar system (Renogy) ready to install at my cabin (when I can get into it)

In the meantime I’ve been testing battery draw on led lights, 12v fan and even a tv running off a 400w inverter.

Until you know what your power draw is, it’s kinda hard to know what you need
The main draw would be a fridge and 1/2 hsp well pump. Led lights, ceiling fan, TV is about it,. probably a microwave too
 
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The main draw would be a fridge and 1/2 hsp well pump. Led lights, ceiling fan, TV is about it,. probably a microwave too
I forgot to mention I plug my fridge in when I arrive at camp and it runs the whole time. I'm thinking of leaving it on permanently during busy season. My system is always on already due to running a hotspot and security cam I can jump in and monitor things. The well pump may be a killer, from what I understand those can get juicy.

edit: On that note, keep in mind that if you're only powered up while you're there at your place then you can simply use the solar for a convenience and kick in the generator as needed here or there.
 
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This is off grid at 9000'.
View attachment 527803

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24 volt system. [note - I would do 48V if I did it again]
5 KW continuous power from the panels
8KW continuous power from the two inverters (surge to to 12 I think)
6 SimpliPhi LiPho batteries. I had AGM's but swapped them out. Only lithiums for me.
Power dump once batteries charged to 3KW elect heater in main room (see small white box next to batteries)
All monitored/controlled remotely via smartthings.
Starlink Internet. It was the only stable internet out there. HughesNet and another were not reliable.
Super clean, love it!
 
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I was thinking about using one of those mats you can install under a tile floor for a heated floor, and insulating the batteries with a foam box??
I can't help you there as it's not something I've had to deal with. Some of the batteries have built-in self heaters so may look into the cost and complexity of just getting those as opposed to trying to mock up something.
 
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Apr 28, 2021
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971
Interesting read . F16 are you running a back up propane generator ? Can you guys comment on brands , good and bad . Curious about propane vs gas
 
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Interesting read . F16 are you running a back up propane generator ? Can you guys comment on brands , good and bad . Curious about propane vs gas
Propane has the advantage that your carbs won't gum up when it sits for a while, but usually generates a bit less power. We turn the fuel off and run them out when we leave and it's not been an issue but other people seem to have problems sometimes. For small systems Westinghouse makes a nice inverter generator for reasonable costs, I'm running Firman and Champion and like them both fine. I suspect F16 has a larger system, I only have experience with smaller stuff.
 

f16jack

WKR
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Utah
Interesting read . F16 are you running a back up propane generator ? Can you guys comment on brands , good and bad . Curious about propane vs gas
Overview. I need a tank of propane to heat my off grid place during the winter. Electricity from panels won't provide enough energy. So, I have a 500 gal propane tank.

I've placed a Kohler generator as the emergency backup. My system monitors the battery level and automatically turns on the generator if the batteries discharge more than desired. Note - the generator loses 3% per 1000 feet of elevation. At 9000' I'm down 27% from rated power. I initially had a Kohler 8.5, thinking I was getting 8.5kW of backup power. Nope, it's 27% lower, only 5.275kW. I wanted to backup 8kW. So I replaced it with a Kohler 12. This is 12kW. At elevation it is derated to 8.75 kW. Meets my needs. The 8kW kept getting low votage faults when I was testing it under loads that it should have been able to handle.

The Kohler 8.5 did a great job for me as I built the cabin. Ran the tools just fine as long as the extension cords weren't too long.

I also cook with the propane. My gas stove has the orifice changed to accept propane.
My clothes dryer is also propane. I also changed the orifice.

There's a trend here. Anything that heats is propane. All else is elec.

As far as brands are concerned, think of availability of service and parts. In Colorado I used a Kohler and am fully satisfied. In Minnesota at another site I use a Generac. Generacs are sold and serviced locally up north - a local electrician said he installs far more Generacs than Kohlers up there. Funny, though. Both are made in Wisconsin. One in Kohler (guess which one) and one in Oshkosh. And here I though Oshkosh just had airshows.

Here you see my propane tank and my new Kohler 12kW installed.
The box on the left is my old Kohler 8.5kW just uninstalled.

1105201142a.jpg
 

Ishisube

Lil-Rokslider
Joined
Mar 9, 2023
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I know a few people living across a bay and it seems that most of them have both solar panels and a wind generator to keep the odds in their favor, but I've never really talked to any of them about their systems. Again, it does seem that whichever type of system they started with, just about everyone ended up with both in the end.
 

f16jack

WKR
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I know a few people living across a bay and it seems that most of them have both solar panels and a wind generator to keep the odds in their favor, but I've never really talked to any of them about their systems. Again, it does seem that whichever type of system they started with, just about everyone ended up with both in the end.
I did a one-year wind study of my Colorado property prior to building. I still have all the data and analysis. It was a class 5 wind area (the highest). But again, wind generators lose 4% per 1000 feet, so I was already 36% below any rated power of any wind generator.
In addition, I looked at neighbors scattered around in the country near me. Some had wind generators, but about half of these were non-functional.
Wind generators, in a hybrid system, require;
  • a hybrid controller. You need a controller that can do both wind and solar
  • maintenance
  • height above trees and structures so as to get less turbulent wind.
I looked at the Kestrel e300i as a wind generator. It was rated at sea level at 1.2kW between 26 mph and 33 mph. At 9000' it only put out 0.76kW at these wind speeds.

I also looked at the SW Windpower AIR-X-24.
With my July wind (measured) the Kestrel only put out 4.36 kWatt hours per day. My panels were putting out 5kW per hour, for a total of perhaps 30 kW hours per day (if I had 6 hours of effective sun).

At the end of the day it was far cheaper, simpler and quieter to simply add some more panels to the roof.
Adding a wind turbine simply introduced too many headaches into the mix without much return.
 

Ishisube

Lil-Rokslider
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At the end of the day it was far cheaper, simpler and quieter to simply add some more panels to the roof. Adding a wind turbine simply introduced too many headaches into the mix without much return.
I've been thinking of doing what those people were doing, having both systems attached to the house, but it sounds like I should avoid the non-solar route altogether then.
 
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THanks for the info on the propane generators . Anyone familiar with "Dakota lithium " out of grand forks north dakota ? It looks like they have all kinds of systems from rv's to off grid houses . If its made there they understand what cold does to things . I'm in minnesota not to far from there and have family in grand forks . Might be worth a look . (pick up and save shipping)
 

f16jack

WKR
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I've been thinking of doing what those people were doing, having both systems attached to the house, but it sounds like I should avoid the non-solar route altogether then.
I had no streams. But if I had running water I woukd have tried out microturbines.
 

f16jack

WKR
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I spent the last two summers building a home just east of Grand Forks and looked into Dakota Lithium. They had a number of products. I was looking for a lithium battery for my jeep. Decided against it. I don't know if they are competitive with Simpli phi. There is also a good lithium battery called the Lifepower 4. EG-4.
 
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Can't say enough good things about the Victron equipment... I have an Airstream trailer and have rooftop solar and ax. jack for remote mounted solar panel.. I used two Victron solar controllers to give me redundancy and room for growth.. With my setup it will continue to charge if any one of the panels is getting sunlight. The one thing I would highly recommend if you're using lead acid batteries is to use 6v golf cart batteries and wire them to get 12v or in pairs if you want to go 24v or 48 v. You will get a longer lasting setup... If you run the risk of freezeups I'd use at least one solar panel to maintain the battery(s).. Lithiums have huge storage capacity/drawdown ability and high recharge cycles, but are super expensive and have strict charger/charging requirements. Best of all worlds would be Batteries/solar with a generator that automatically kicks on when the battery reaches a defined voltage limit.. That would allow use to use an invertor and not have to worry so much about draining the batteries. If you can run everything on DC you'd be ahead of the game since the conversion will cause a loss. Good luck with your solution...

Have a friend who is an electrical engineer who installed a Tesla battery bank (came from wrecked Tesla and bought on Ebay) in his travel trailer.. Got it pretty cheap and is super happy with it.. He runs his air, microwave and everything off it ( not continuiously, but as needed.
 

Ishisube

Lil-Rokslider
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I had no streams. But if I had running water I woukd have tried out microturbines.
That's a lot harder to come by but I like the idea of getting electricity from the river or a good running creek and one of my friends has a strong running creek at his property that was able to move vehicles this last summer, making me wonder if he couldn't be getting power from it. Be interesting to know more about systems that could derive power from water, be it one direction, or tide water in the case of some of my other friend's places.
 

sneaky

"DADDY"
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Will Prowse as already mentioned is a great resource, as well as Ben at Minute Man Prep on YT. I'm a little biased since I've been to Ben's house a couple of times and spoken to him at depth about the solar generators/ batteries/ panels. He's here in Idaho, and he's a big 2A supporter.

He has a cabin that he runs completely off grid and has several videos on his channel of what he's running it off of.

Sent from my SM-G955U using Tapatalk
 
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