Cabin solar

[Tcataz]

I am in the process of building a smaller simi-remote cabin. We currently have a wall tent we have left there. The cabin is 512 SF in Prescott AZ. The area does get some cold but not for long. We plan on using the cabins a few weekends a month and an occasional week stay. It will be mostly used for a summer cabin with few trips up in the winter. The cabin heat is wood fire place, supplemented by propane. It will use propane for the water heater, stove and refrigerator. We used the dometic fridge occasionally. I would like to setup a solar/generator system. I currently have a Honda 2200i. I can use it for supplement when I want to run larger things such as vacuum, microwave etc. I did an energy audit and at the very extreme I will use 2,500 W-hrs a day. This is if I have everything ever thought I would need up there. Most of the time it will just be some lights and may be a radio. So realistically is is around 1,500 W-hrs. That area looks to get about 5.6 Average Sun Hours per day. Of course we will use most in summer. Nothing really needs to be left on when we leave so we will put in cut off switches. We plan on spending most of the time outside. I am look at two options:
1) One of the 1000W 12V MPP Solar all in one units with 400 Amp hours of battery with 500 watts of solar. But I heard the inverter is a power hog. Can that be shut off when not there? With the all in one can you cut off everything and just have it charge batteries?
2) Get 500 watt of solar, 40 Amp MPPT Charge controller, 200 amp ours of battery, 2,0000 Watt inverter, and transfer switch.

Looking for opinions if one is better than the other or am I way off base with everything.

 

[Bluedog225]

Welcome to the forum. May need some more info. The specific voltage of the panels needs to be taken into account when picking a controller (or vice versa). And how you plan to put them together matters (string/parallel). But in general, you are in the right neighborhood. I’d plan the entire system out (with specific parts) before buying anything and limiting your ability to make changes based on feedback.

 

[Rednecktek]

Aarrgghh! I can't copy & paste my standard newbie to-do post on a phone!!

 

[MichaelK]

For even a small cabin, I'd start out with at least 24V. My very, very first cabin system was 12V and I regretted it. The better electronics start out at 24V, and higher voltage helps cut down on wiring costs, and the size of your controller.

Here's what I would do. Get at least 200Ah of battery, at 24V, and 1000W of panels instead of 500W. If you got three 330W panels you could mount them on a single-pole mount like this, and by rotating east to west you'll be able to make 5kWh per day in December. Leave facing south and it will make 3kWh. A 40A, 150/200V MPPT controller will handle all the amps this array could put out on a 24V system.

Get a 2000W inverter and you'll be able to power a refrigerator, air-conditioner, and all the other household electronics we live with every day. Personally, I went with a Conext 4024, which I am very happy with. Besides just inverter, it makes split-phase 120/240VAC, and has a built-in generator charging circuit you just wire into the wall. That way you don't need a transfer switch for your generator. It only consumes about 20W at idle.

 

[Tcataz]

Welcome to the forum. May need some more info. The specific voltage of the panels needs to be taken into account when picking a controller (or vice versa). And how you plan to put them together matters (string/parallel). But in general, you are in the right neighborhood. I’d plan the entire system out (with specific parts) before buying anything and limiting your ability to make changes based on feedback.

I was thinking of getting 3-200 W panels and wire them in series. Each panel is 200W, 20V, 9.80A.

 

[Tcataz]

For even a small cabin, I'd start out with at least 24V. My very, very first cabin system was 12V and I regretted it. The better electronics start out at 24V, and higher voltage helps cut down on wiring costs, and the size of your controller.

Here's what I would do. Get at least 200Ah of battery, at 24V, and 1000W of panels instead of 500W. If you got three 330W panels you could mount them on a single-pole mount like this, and by rotating east to west you'll be able to make 5kWh per day in December. Leave facing south and it will make 3kWh. A 40A, 150/200V MPPT controller will handle all the amps this array could put out on a 24V system.

Get a 2000W inverter and you'll be able to power a refrigerator, air-conditioner, and all the other household electronics we live with every day. Personally, I went with a Conext 4024, which I am very happy with. Besides just inverter, it makes split-phase 120/240VAC, and has a built-in generator charging circuit you just wire into the wall. That way you don't need a transfer switch for your generator. It only consumes about 20W at idle.

Thinking that is a little much for a cabin we use a couple times a month. There is no AC and fridge is propane. We got to the cabin to escape electronics. We have stayed the last 3 years in a wall tent on the property which had not electricity.

 

[MichaelK]

Thinking that is a little much for a cabin we use a couple times a month. There is no AC and fridge is propane. We got to the cabin to escape electronics. We have stayed the last 3 years in a wall tent on the property which had not electricity.

I suppose I can understand that. Once the wife gets to use her hair drier the first time, it's all over.

 

[Tcataz]

I suppose I can understand that. Once the wife gets to use her hair drier the first time, it's all over.

I 22 years of marriage I think I have seen my wife use a hair dryer a dozen times. My wife is very outdoorsie type. She loves camping and being out hiking.

 

[Scoutmaster]

So I have a similar rustic cabin 26x26ft….and my DIY system is working decently. I agree that once you get a “sniff” of more power you might want it.

My cabin:
2 SOK 100ah batteries.
400w solar(4x100w renolgy)
2000 W inverter Krieger.
Renology Solar Controller
-car battery charger

I can run 5 strings of Cosco string lights, TV, and charge basic electronics. I run a coffee maker and shop-vac briefly each day. So far it works. I can charge my eBike and power tools. The system I have was very cheap and works pretty well. I use 2 power strips and have one for this system and 1 for my generator power. I just move the plugs if running the generator.

I also have a 4000 and 2000 watt generator for back-up I use in the winter. My cabin is several miles from the car so I have a back-up just in case.
I am thinking of upgrading to the MPP/Growatt and 1600w Solar and 400ah so I can run a fridge and real lights Etc.

 

[12VoltInstalls]

am thinking of upgrading to the MPP/Growatt and 1600w Solar and 400ah so I can run a fridge and real lights Etc.

What is your location? Battery storage seems small - you’ll need 1600W to even do 200W if you’re northern latitudes located.

I run 12V lights that are pretty real and very low consumption

 

[Scoutmaster]

I agree I might need 1600w in Solar panels just to get any measurable solar during the winter. I think last winter I was getting barely 2 hours at max. Between the deep snow and a very short solar window I think my generator and battery charger will be doing the heavy lifting.
I visit weekly to Ski so removing the snow won’t be super difficult. I think 8 lead acid for the winter months and possibly 400ah lithium for the summer might be the minimum to stay reasonably powered.