off-grid electrical system for cabin

[timberland]

going to try to develop a 2000 W electrical system for a cabin. with all the solar components available, I was thinking of starting with a generator feeding a charger/invertor and a battery bank. I don't necessarily need the solar panel support at this time, but may add it in the future. I already have the generator, looking for recommendations on an invertor and battery system.

Any recommendations?

 

[akcabin]

We've used a vehicle battery for years. Charge up 2 batteries with the generator while doing other chores. Then used those to power any electronics. We use a 12v pump for showers and will use for the well pump. Been using those batteries 5-6 years now. And they freeze hard every winter. I've never done anything to them except charge them.
Good luck on your cabin

 

[BigE]

Lots of names out there but Victron is what we went with and it's been great. Also you can add components as you need or want.

EDIT: Sorry skipped the battery section. Lots of options and all depends on budget. Lithium is great but more $$$. Discover batteries have been solid for us.

 

[MallardSX2]

For as much as you are going to use your cabin, I would just charge up a handful of batteries. I would not be drilling holes in my roof or dealing with any form of solar. You can buy a generator and a LOT of non-ethanol gas to go with it for what those solar panels are going to cost you. And to replace something that gets broken is very simple.

 

[*zap*]

A few smaller invertors placed around where you might need them vs wiring outlets and one main invertor to power the outlets may be the way to go unless the cabin is already wired. Generator vs solar to start and maybe add a panel or two later.

 

[fmyth]

Will Prowse has one of the best Youtube channels on solar:

If you want to punch the easy button just get one of these all in one solutions and be done with it:

Buy EcoFlow DELTA Portable Power Station - EcoFlow US

Official EcoFlow DELTA Portable Power Station: Power Source: ‎AC/DC ✓ Battery Cell Type: ‎Lithium Ion. Click to learn more!

us.ecoflow.com

 

[doc holiday13]

12v everything if you can.

 

[ChrisS]

For as much as you are going to use your cabin, I would just charge up a handful of batteries. I would not be drilling holes in my roof or dealing with any form of solar. You can buy a generator and a LOT of non-ethanol gas to go with it for what those solar panels are going to cost you. And to replace something that gets broken is very simple.

solar panels are cheap. It's the batteries, components, and wiring that are $$.

going to try to develop a 2000 W electrical system for a cabin. with all the solar components available, I was thinking of starting with a generator feeding a charger/invertor and a battery bank. I don't necessarily need the solar panel support at this time, but may add it in the future. I already have the generator, looking for recommendations on an invertor and battery system.

Any recommendations?

This complete kit (and Will Prowse has some videos on it) is $8k and has three batteries ($1200/per).

Complete Off-Grid Solar Kit - 3000W 120V Output / 48VDC [15.4kWh EG4-LifePower4 Lithium Powerwall] 48VDC + 4,740 Watts of Solar PV | [KIT-E0001]

3000W Off-Grid Solar Kit with 48V Lithium Powerwall and 4800W Solar PV: Complete off-grid solar solution featuring a 3000W solar inverter, a 48V Lithium Powerwall for energy storage, and 4800W solar PV panels for efficient energy generation.

signaturesolar.com

For our small hunting club cabin, we're just going to spend the coin on a lithium battery and an all-in-one. You could design your own, but there's a pretty steep learning curve. I don't have the time or interest to monkey with repurposing chevy volt batteries and cobbling together components that meet code.

We'll start with one battery and add on if we need it depending on how everything works. We have a big honking honda genny to boost the charging during the day or evening whle we're running some things, but there's no reason to run the genny all night just because someone needs a CPAP or to put the TV on for an hour in the morning to watch the weather. There'll never be power lines on our road, and this club has been operating since the early 60s and shows no sign of slowing down, so we should see any savings that solar eventually gives us.

 

[bow puller]

Will Prowse is a great source. I upgraded the system on my toyhauler with lithium batteries in a (auto below 40) heated enclosure, new converter/charger, added add'l solar and changed to Victron. Only thing left original is Cummins Gen. Basically a rolling off grid cabin.

Estimate your power needs then size accordingly. Lithium batteries are amazing compared to lead- as long as you don't charge them below freezing. Solar panels are cheap nowadays and I wouldn't be without them or a generator.

 

[ScreamingPotato]

So I have a fish camp on an island at the coast where we run all solar during the winter, really only need to run the generator when it's summertime and we want the a/c going. In Texas that's quite important. Unless you're running a microwave or something you probably don't need 2k watts inverter. I have a few lessons learned over the years while setting this all up and upgrading components. I used to just use lead acid batteries, trolling motor batteries from my boat actually. We killed those dead as a doornail really fast. 6 volt deep cycle golf cart batteries went in as replacements and they were great for about 6 months, again we killed them. Lead acid doesn't like to be hit so heavily. I finally put in a couple big LifePO4 batteries and it's crazy how big the difference is. If you want the system to last and not have to constantly monitor your batteries trying not to go less than 50% then skip the lead and go with lithium. Solar panels, I have two old 100 watt Renogy panels and two new 195 watt Eco Worthy (Amazon Chinese junk) panels, the two original Renogy panels outperform the 195 watt panels through all my testing. Keep that in mind. Renogy isn't the best name brand or anything but they're clearly better than the Eco's. Bigger systems will usually perform better at higher voltage but for simplicity I went back to 12v wiring even with multiple batteries, for our purposes the benefits of wiring the higher voltage from the panels don't really matter, it's just a small system afterall. My charge controller gets HOT when all four panels are kicking at high noon and it's close to maxed out, if I were to do it again I'd oversize the charge controller hoping to keep the temps down a bit. On that note, don't bother with PWM and just go straight to a good MPPT controller, you'll end up wanting to upgrade it later anyway.

I work "from home" from this camp for a week at a time or so, watch TV and run fans and charge all my phones and laptop and headlamps whatever, all the lights, two huge floodlights outside, water pump for the outhouse, inside lights all that, also charge all my power tools while rebuilding, my giant bluetooth speaker, everything. If I need to microwave something I'll fire up the generator, or use the A/C of course. If my inverter was bigger I could easily run the microwave but we rarely use it anyway since we're usually grilling or cooking on a propane stove.

edit: Maybe worth noting, this is a fish camp so it's all been hodge-podge and cheaply built and upgraded piece by piece over time. I installed a breaker panel on the cabin and ran two feeds to it, one feed going to the generator 30 amp plug and wired the heavy power breakers to it, all the rear and countertop outlets, a/c, microwave, etc. The 2nd feed only runs the breakers for the inside lights, outside lights, and outlets by the front door. I wired that to a standard plug and can just manually switch that back and forth between the generator and the inverter as needed. After getting the new batteries it just stays in the inverter full time anyway. I built a small shed to house the solar panels (no holes in your roof) and generator, batteries, tools and such. That keeps everything safe and dry and secure and I just fire up the generator in there when needed.

 

[timberland]

So I have a fish camp on an island at the coast where we run all solar during the winter, really only need to run the generator when it's summertime and we want the a/c going. In Texas that's quite important. Unless you're running a microwave or something you probably don't need 2k watts inverter. I have a few lessons learned over the years while setting this all up and upgrading components. I used to just use lead acid batteries, trolling motor batteries from my boat actually. We killed those dead as a doornail really fast. 6 volt deep cycle golf cart batteries went in as replacements and they were great for about 6 months, again we killed them. Lead acid doesn't like to be hit so heavily. I finally put in a couple big LifePO4 batteries and it's crazy how big the difference is. If you want the system to last and not have to constantly monitor your batteries trying not to go less than 50% then skip the lead and go with lithium. Solar panels, I have two old 100 watt Renogy panels and two new 195 watt Eco Worthy (Amazon Chinese junk) panels, the two original Renogy panels outperform the 195 watt panels through all my testing. Keep that in mind. Renogy isn't the best name brand or anything but they're clearly better than the Eco's. Bigger systems will usually perform better at higher voltage but for simplicity I went back to 12v wiring even with multiple batteries, for our purposes the benefits of wiring the higher voltage from the panels don't really matter, it's just a small system afterall. My charge controller gets HOT when all four panels are kicking at high noon and it's close to maxed out, if I were to do it again I'd oversize the charge controller hoping to keep the temps down a bit. On that note, don't bother with PWM and just go straight to a good MPPT controller, you'll end up wanting to upgrade it later anyway.

I work "from home" from this camp for a week at a time or so, watch TV and run fans and charge all my phones and laptop and headlamps whatever, all the lights, two huge floodlights outside, water pump for the outhouse, inside lights all that, also charge all my power tools while rebuilding, my giant bluetooth speaker, everything. If I need to microwave something I'll fire up the generator, or use the A/C of course. If my inverter was bigger I could easily run the microwave but we rarely use it anyway since we're usually grilling or cooking on a propane stove.

edit: Maybe worth noting, this is a fish camp so it's all been hodge-podge and cheaply built and upgraded piece by piece over time. I installed a breaker panel on the cabin and ran two feeds to it, one feed going to the generator 30 amp plug and wired the heavy power breakers to it, all the rear and countertop outlets, a/c, microwave, etc. The 2nd feed only runs the breakers for the inside lights, outside lights, and outlets by the front door. I wired that to a standard plug and can just manually switch that back and forth between the generator and the inverter as needed. After getting the new batteries it just stays in the inverter full time anyway. I built a small shed to house the solar panels (no holes in your roof) and generator, batteries, tools and such. That keeps everything safe and dry and secure and I just fire up the generator in there when needed.

Great idea of have the larger draws slaved to the generator. What size invertor you have now and what would you go to? Your draw needs look very similar to mine

 

[ScreamingPotato]

Great idea of have the larger draws slaved to the generator. What size invertor you have now and what would you go to? Your draw needs look very similar to mine

I'm just running a cheap 750 watt inverter, always planned to upgrade it but so far no need. I even ran a table saw on it (plugged into the cabin) and air compressors and such. The MPPT charge controller is a 40 amp and it starts getting hot at 30 amps coming in from the panels. I think in hindsight I'd go ahead and get a 60 amp charge controller just to tax it less, though power coming in is probably generating a similar amount of heat I'd have to imagine that a 60 amp controller would dissipate it better, maybe?

 

[f16jack]

Panels, 48V system, Lithium batteries. Propane Backup Generator.
I've run Lead Acid AGM batteries. Only SimpliPhi LiPho batteries for me.
I'm running a year-round off grid cabin at 9000' in Colorado.

 

[fmyth]

I'm just running a cheap 750 watt inverter, always planned to upgrade it but so far no need. I even ran a table saw on it (plugged into the cabin) and air compressors and such. The MPPT charge controller is a 40 amp and it starts getting hot at 30 amps coming in from the panels. I think in hindsight I'd go ahead and get a 60 amp charge controller just to tax it less, though power coming in is probably generating a similar amount of heat I'd have to imagine that a 60 amp controller would dissipate it better, maybe?

Is it possible that your charge controller is not rated for the max voltage your panels are producing?

 

[ScreamingPotato]

Is it possible that your charge controller is not rated for the max voltage your panels are producing?

It's an Eco-Worthy, so anything's possible lol. It's supposed to be rated for 40 amps but I haven't seen it get to 40 amps just yet with these panels. I don't recall what voltage it was charging at when I saw 30+ amps so it's possible it was pushing 40 @ 12v assuming that's what the 40 amps is rated at. When I say really hot I don't mean it's unreasonably or dangerously hot, it's just hotter than the old Renogy PWM controller ever got. I think it's probably fine but I like less heat if possible.

 

[ScreamingPotato]

Panels, 48V system, Lithium batteries. Propane Backup Generator.
I've run Lead Acid AGM batteries. Only SimpliPhi LiPho batteries for me.
I'm running a year-round off grid cabin at 9000' in Colorado.

I assume your batteries have heaters yeah?

OP that's something to consider if you're in an area where temps drop low, lithium won't charge if it's below freezing so you need batteries with built-in heaters or some way to heat them. I don't have to worry about that on the coast.

 

[f16jack]

I assume your batteries have heaters yeah?

OP that's something to consider if you're in an area where temps drop low, lithium won't charge if it's below freezing so you need batteries with built-in heaters or some way to heat them. I don't have to worry about that on the coast.

I have a utility room and the batteries are in that room. I keep the cabin heated year round, so the utility room is always warm.

 

[cnelk]

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

 

[timberland]

I assume your batteries have heaters yeah?

OP that's something to consider if you're in an area where temps drop low, lithium won't charge if it's below freezing so you need batteries with built-in heaters or some way to heat them. I don't have to worry about that on the coast.

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??

 

[f16jack]

This is off grid at 9000'.





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.