My off-grid setup plan - Small Cabin Forum

- Forums - Register/Sign Up - Reply - Search - Statistics -

Small Cabin Forum / Off-Grid Living / My off-grid setup plan


Author	Message
NovaDC Member	# Posted: 23 Jan 2023 09:49pm Reply Hi everybody. This forum has been a great resource and I try not to post questions in general before I have done quite a bit of research already. So, I think it is now time - and... my head is spinning - so would really appreciate some advice. We are planning on building a cabin on our woodlot this year. Last year we were able to put some gravel down, build a storage shed, an outhouse and cleared some trees in prep. We currently have an 25ft travel trailer which has a solar system on it; 800w of panels, 60A MPPT, 4 x 100Ah 12v lifepo4 batteries and no inverter. It has worked really well for us and runs our 12v fridge non-stop. Now that we are thinking about all things cabin. We have a budget and I like to get my monies worth and think of out-the-box solutions where I can. So, the plan includes the following: Solar: We were thinking a complete off-grid system for the cabin, but I had an idea of beefing up the system of the RV and running a cable to the cabin for power. The reason for this is we travel quite a lot, the cabin will be fairly recreational and don't like the idea of either fairly expensive solar system not being used and left unattended in the woods for long periods. It would be great to have an all-in-one mobile solution. This is where I have got to with that idea; purchase a good 12v 3000w inverter/charger with marine grade 4/0 wire (inverter next to batteries and all inside the RV under the dinette). Wire in a 30A outlet wire to the inverter and install a female 30A socket on the outside of the RV. Run a 6awg 50ft+ (don't know the distance yet) cable to the cabin where there will be a male 30A socket on the outside, wired into a sub panel on the inside. Cabin will have an energy efficient fridge/freezer - standard size and will also power laptops, phones, lights and the occasional appliance and that's about it. I see the weak point being the flat-mounted 800w of solar on the RV roof in the winter. We do have a backup generator. We could also purchase 1 or 2 more 200w panels for the roof and upgrade the SCC if we thought it would make a decent difference. The big sticking point from the power POV was the well pump as I see on average they draw 1400w. So, my plan there is, I see you can get 12v deep well pumps. No idea about how good these are and info on them is a bit scarce. So any feedback would be great. I would then buy second hand panels, inverter and a couple of agm batteries and give it, it's own 12v solar system. My neighbour's well is 122ft but I know this may not mean much for mine. I then don't know the best way to hook it into the cabin - it will have 2 sinks and 2 showers (1 outside) for 2 people. The well itself, we are getting quotes of around $7-8k. We are not near a water source so just accepted that we will have to stump up the cash, even though it will take a big chunk of the budget. I realise some of these ideas are maybe not the industry standard ways of doing things or will even work well at all but I'd really like to try and explore them. Any ideas are very welcome! Thanks

gcrank1 Member	# Posted: 23 Jan 2023 11:23pm Reply My place, built by the prev owner, came with a 600W solar array into a 50A mppt scc to 4x125ish ah agms (effectively 200ah available). It would have been so much better with your set up, but had been 'adequate' until the agms died off one at a time. Now we have 2x100ah lfp; game changer that, but still only 200ah available. I love not having to be OC about recharge asap, etc. that LA requires. The other game changer has been our 1700/2000 peak inv. genny. Our 'big' loads tend to be short so we run the gen for those. The rest runs off the bats inverted to 120vac. I initially rewired the poorly installed solar into a 12vdc, then re-wired again as split voltage 12vdc/120vac, then went inverter to full 120vac and havent looked back. Btw, imo a 3000w Pure Sine Wave (do not even consider a MSW model!) inv. means a 24v or even 48v system or the size of the wires and fusing required gets huge, hard to work with and expensive. Keep the inv to 2000 max for 12v (I max my 12v system at 1000W inv; more load than that I run the gen). By using all 120vac I could use a small 'add-on' 2 fuse/circuits box, std switches and house type fixtures with cheap Edison base LED bulbs (so low a draw it doesnt matter). As to the run from camper to cabin of 120vac, what do you plan to run in the cabin that would require 30a? Typical house wiring is 14ga. for 15a with a few 20a outlets requiring 12ga., 30a is 10ga). Fwiw, we ran about 100ft to the cabin from the inv with a 10ga. 'contractors grade' extension cord. When I needed more power I could unplug at the inv and plug into the gen (ie, I was the transfer switch). A fancier inv could have a 'pass through/internal transfer'. I checked for voltage drop in the cabin with my Fuke and have nothing of consequence. You could run the well off the gen, pump to a surface holding tank (think IBC tote) and power cabin water with a small pump. The splitting the basic 90%? cabin elec load run off the inverted bat power and the big loads to gen worked out very well last year, the best ever, and so simple it made me wonder why it took me so long to figure it out

Brettny Member	# Posted: 24 Jan 2023 05:59am Reply Are you going to visit the place when it's cold? Below freezing cold.

NovaDC Member	# Posted: 24 Jan 2023 09:22am Reply Initially I was going to try and run the well pump from the inverter but I didn't like this idea, so yes, a 2000w inverter is a better idea. To be honest I am not sure about the 15/30A wiring thing - I was under the impression a 30A would be better just in case and what with a fridge etc, 1 x 15A wire wouldn't be sufficient. I am just learning about electricity and a uncertain on...well quite a lot! I have a pretty good idea of what we will be running - I suppose the biggest thing once a week for 10 minutes would be a hair dryer and a 1400w blender (not at the same time obviously). If we could use a 15a extension cord then that's even better. I was looking at holding tanks for the water but if outside would it not be susceptible to freezing? I initially designed the cabin so there would be room for a small pressure tank in a cupboard - would these work? If going holding tank route then it would require an ac pump, not sure how much power these use? Still need to research the whole 12v/24v deep well pump thing but you are saying I could run an AC well pump from a generator into a large holding tank then a small pump off the inverter in the cabin? Quoting: Brettny Are you going to visit the place when it's cold? Below freezing cold. Yes, we plan to spend all of next winter in it, if it gets done on time! We're in Nova Scotia - the winters are not too bad here but can get very cold for spells. We also are planning a wood stove (plenty of firewood already cut), a propane on-demand hot water heater and a propane stove. Thank you

travellerw Member	# Posted: 24 Jan 2023 09:53am Reply Not sure how close you are to any towns.. but most towns (at least here in Alberta) have a water station. Instead of paying the 10K we were quoted for a well, we opted to haul our water. We bring it on a trailer with a 1000L tank. The cost to fill the tank is $9. 1000L will last us about 3 weekends (5 of us). For us, its a 15 min drive to the water station, so not a big deal every 3rd weekend. Of course this doesn't work in the winter as the tank would freeze. So our cabin is dry in the winter and we just bring 20L of water for cooking, washing dishes, toilet flushing, ect. I will also comment on your 12V inverter. If you do the math a 2000W inverter will draw 145 amps @ 13.8V. Even with giant cable and a short run, that is a whole crapton of amps to pull. Especially if its sustained for more than 30 seconds or so. Its possible, but not the best solution. For loads above 1500W its pretty common to have a 24V or even a 48V system. One other thing.. Plan on having a generator for winter. Seriously, with the change in sun angles and the clouds you can have days where you get NOTHING.. Yup zip zilch nada for power out of your array. I have seen my current 400W setup put out no more than 2w for like 5 days straight.

Nobadays Member	# Posted: 24 Jan 2023 09:55am Reply Quoting: NovaDC I was looking at holding tanks for the water but if outside would it not be susceptible to freezing? Yes. This is what we have/had. Last summer we put two 200 gallon tanks under the cabin and valving so we could drain and winterize the outside cistern... then switch over to the under cabin tanks when freezing weather hit. Both the outside and under tanks have independent RV pumps to provide/ pressurize the cabin water system. I will add that our cabin is on piers with metal skirting. The skirting and under the floors have 4" of spray foam insulation. This winter we have seen temperatures to -14Â°F but a thermometer under the cabin never showed less than 38Â°F. Worked beautifully!

Nobadays Member	# Posted: 24 Jan 2023 09:57am Reply Quoting: travellerw For loads above 1500W its pretty common to have a 24V or even a 48V system. One other thing.. Plan on having a generator for winter. Seriously, with the change in sun angles and the clouds you can have days where you get NOTHING.. Yup zip zilch nada for power out of your array. I have seen my current 400W setup put out no more than 2w for like 5 days straight. This! Great advice!

NovaDC Member	# Posted: 24 Jan 2023 10:22am Reply Thank you for this. Hauling water is not an option unfortunately - there is nothing local, plus, we would like to have a solution that we can use in winter. The well is the one thing we have resigned to spending a lot of money on as I think it would be worth making that investment early. Going 24 or 48v would either mean a whole load of modifications to our current system in the RV including replacing the batteries (the ones we have do not allow wiring in series). Or, installing a cabin specific solar system - something I am trying to avoid for cost and efficiency reasons. We do have a generator - a 4000w duel fuel. We could run this when using hairdryer / blender if that's the best idea.

NovaDC Member	# Posted: 24 Jan 2023 10:27am Reply Should also maybe point out - we plan to live in this cabin for several months of the year - possibly over winter some years.

Steve_S Member	# Posted: 24 Jan 2023 11:15am Reply Gonna chime in with some quick details / thoughts. Focus is on Cabin, not the RV. still on coffee #1 so bear with it, LOL 12V systems can support up to a 2000W Inverter. This would pull 166A to provide 2000W. This would provide 120V/16A 24V can support up to 5000W (4000 is better). @4000W pulls 166A, 5000W = 208A pull. This would provide 120V/33A or 120V/41A from 5000W. ! Not Corrected for inefficiencies or losses. * general unwritten rule is to not pull more than 250A from a battery system (regular loads, excluding surges from starting motors such as fridge/freezer compressor or pumps). ---------------- I would recommend a Component Based Solar System for the cabin and NOT an AIO (All-In-One) which would allow you to shut everything off except for the SCC (Solar Charge Controller) to maintain batteries while away / not in use. AIO's carry a higher overhead standby usage and the majority are High Frequency models using FETS instead of Torodial Transformers like Low Frequency Inverters. REF to read: https://www.magnum-dimensions.com/knowledge/high-vs-low-frequency-inverters/inversion -methods-explained-high-frequency-vs-low -------------------------- I would recommend a Low Frequency Tier-1 or Tier-2 Quality Inverter/Charger - stay away from the "Value Grade" cheapo devices ! Hint, Renogy = Run Ohhh Geez. -------------------------- I am 100% offgrid near Algonquin Park. I run on 24V 1294AH/33kWh LiFePo4 (LFP) using a Samlex EVO-4024 Inverter/Charger & Midnite Classic SCC (Solar Charge Controller). My Deep Well Pump is a 120V/Soft-Start GrundFos SQ5 which is 280' deep pushing to a 50 Gallon Pressure tank and then 75' to house. It starts at 550W and stages up to 1300W by the time it reaches 50PSI cutoff. More details about my system is located here, you will find a lot of info there: https://diysolarforum.com/threads/my-diy-off-grid-cabin-setup-in-ontario-canada-24vdc -120vac.1484/ Within that Thread, it also shows you how the 120VAC Square-D Panels are wired and more. ---------------------------- Solar Panels: Cabin. The best option for a cabin is to have a Ground Mount system, if "fixed" it should be set to optimal annual angle but an adjustable will allow you to adjust the angle for best production per season. See THIS Link for a respectable Solar Panel Angle tool: http://www.solarelectricityhandbook.com/solar-angle-calculator.html Panels are cheap in the grand scheme of things and the right solar charge controller uses less panels to generate lots of charging power. For Example, I am installing an array of 6 395W QCell Solar Panels (2S3P) connected to a Midnite Solar Classic 150 SCC that will provide 94A Charging for 24V Battery Bank. In my case this is going in Parallel with my existing Classic-200 which will be Master Controller in my setup. ------------- Construction: You can opt to put panels on your roof BUT roof angles have to be reasonable and facing the correct directions. Note that a 45 degree Angle = 12:12 Roof Pitch. My own panels are set at 45 Degrees for optimal year round fixed installation but Ground Mounted. You have two options, A Roof Face aimed south in an East-West orientation OR in North-South orientation can provide Morning & Afternoon Sides for power generation. This could allow for 2 SCC's and double the panels. --------------- Other general notes: Due to my location and amounts of snow (crap loads of it) I do have to run a Genset to Maintain Batteries in mid-winter occassionally (hence the 2nd array coming online in spring). I use the L5:30 Plug on genset to feed my Inverter Charger which is charging at 80A, this uses 120V/23-25 Amps from the genset. It floats a little due to Passthrough power to house. The Genset I am using for this is a Champion 201079 *NOTE: Pure Sine Inverter Generator, they also have Multi-Fuel models with Electric Start. These are NOT AGS compatible. AGS = Auto-Gen-Start module. My system is quite capable and provides the power I need & use. It is capable of handling my 120V MIG Welder, my 3HP Compressor, well pump and everything else without a blink (Note though that I use a Tier-1 High Quality Inverter). AS YOU ARE BUILDING FRESH I would suggest that you may seriously want to consider making your cabin 240VAC from the start and yes 24V will do it too but is more limited. Things change constantly and so does our usages, it's better to be able to accommodate the future in the initial design & implementation. At minimum be "wired ready" for 240V as you do not want to rip things apart to rewire or to add in wiring. Also consider eventual resale as many people will consider that as well. Hope it helps, Good Luck

gcrank1 Member	# Posted: 24 Jan 2023 11:34am Reply LFP batteries can be discharged down to freezing, even a bit below, but Not Recharged unless they are above freezing. I too am stuck with 12v in my legacy system. If I had been starting fresh Id have gone 24v; oh well.... Fact is the 12v with my little 300w psw inverter does all that is needed for most of everyday living and the gen picks up the rest. The 1Kw psw inverter is my next indulgence upgrade to wire in this next season. When the gen runs we do as much stuff as possible (a little planning) to make the starting (pull) and running worthwhile. A good 'pass-through' inverter/charger would help charge your bat-bank when ever the gen runs and be seamless for the family. A fancy set up could have a low voltage trigger that starts the gen (if elec start) when the bat-bank falls to x volts. 4Kw gen would be overkill for most stuff in our cabin life but we only run ours for short term heavy loads (16x24 simple cabin), but ya got it, use it. Hope it is elec start (for winter use!) and with dual-fuel its good to go without the gas going bad (3mo ime with eth-blend). Dont use a cheap consumer grade 15a extension cord! Get a 20a heavy duty 'contractor' cord. Your gen may have a 20a outlet? Even if not use the better cord. The next 'upsize' would be the very heavy duty RV 30 or 50a cords. Sometimes 25' or 50'ers show up on Craigslist or go to an RV salvage yard and retrieve one (may have to cut or disconnect from the units power converter). It never hurts in use to have the 'bigger cord' but they are expensive if bought new.

travellerw Member	# Posted: 24 Jan 2023 12:10pm Reply I agree with Steve about a cabin solar system. IMHO its the only way you are going to make this work if you plan extended stays.You are heading down a rabbit hole though. Solar forum will be your friend. You will find tons of good and bad information, so be prepared to sift. Just know, things are different north of the 49th, especially in winter. Days are shorter, sun looses most of its power, cloudy, snowy. Its VERY hard to supply even modest needs on solar in a Canadian winter. Unless you put up a pretty big array. However, I have another question. Sewage? What is your plan here? Hell, the sewage system for our property was more than a well (like 17-20K). Unless you are remote enough to get away with a tank and surface discharge, but that doesn't work in winter (plus just a tank can be 4K). Others have done an underground storage tank and suck truck. However since hauled water is not an option, I'm guessing that would be out too.

NovaDC Member	# Posted: 24 Jan 2023 12:13pm Reply Quoting: Steve_S I would recommend a Component Based Solar System for the cabin and NOT an AIO (All-In-One) This is great advice and hadn't thought about that - for when the time comes to build a cabin system. Which may be a while. But would really like to see how we get on with the RV powering the cabin. So, what you are saying is 2000w would be okay - not great - but okay. I have been looking at the Victron Multiplus inverter/charger. Reasonably expensive, but a lot cheaper than a new cabin solar system. As it would be to invest in a 30a cord. Thanks guys - head still hurts but getting there! While doing all this - I got another quote for the well - over $16k! for 120ft (including all the pumps etc). So, I am now thinking to do a rainwater collection system!

NovaDC Member	# Posted: 24 Jan 2023 12:18pm Reply Quoting: travellerw Sewage? What is your plan here? We have an out house and will look into an interior composting toilet. The grey water will go into a branch drain system (we are on a hill). I may give up on the cabin being powered by the rv but would like to exhaust all avenues. I am convinced (hopeful) that there is a way to make all this work! Really good to be chewing this over with folks in a similar boat - thank you.

travellerw Member	# Posted: 24 Jan 2023 12:41pm - Edited by: travellerw Reply Quoting: NovaDC I am convinced (hopeful) that there is a way to make all this work! Everything is possible.. but sometimes not the best path to go down. While there are upsides to using your RV (removing the panels when you aren't there), there are loads of downsides too. The biggest would be panel angle. Unless you designed your RV system to tilt, you are stuck with flat panels. That would be an absolute killer in spring, winter and fall. In any case, don't get discouraged, this is supposed to be fun. Mull it over, come up with a plan and be prepared to pivot at any point. P.S. There are many ways to skin a cat. I don't think anyone here has solved the problem them same way as someone else. Yet there are many successes!

Steve_S Member	# Posted: 24 Jan 2023 12:51pm Reply Rain Water is NOT Potable - you cannot drink that safely anymore. You have to filter & treat it nowadays. If anyone tells you different, walk away and don't say a thing. I have a Grey Water System which takes the kitchen sink, shower, urinal & toilet urine diverter output. Simple enough system goes to a Filter Tank then to a 50 Gallon Dry-Well that has two 50' runs of 4" O-Pipe in gravel trenches running downslope. I use a Sawdust/Woodchip dry toilet which produces no smell or toxic black water (urine is diverted out). This goes to a Composting setup that composts for 2 years. This is no problem in my region which is harsher than yours. NB use only softwood sawdust & chips and NEVER EVER use Cedar ! Grey Water System is located 80' downslope from the Well and the composting area is 150' downslope from the well. WARNING: Every region/area has rules as to what you can & cannot do and most especially when it comes to water sources and sewage/waste management. You really do NOT want to run afoul of those rules as that can get very costly very quickly. Be aware of the rules, regs & codes as applied to your location specifically. This is often tied to how the property is designated and classed, as well. I also have a thread that covers PART of my Cabin Build and the grey water setup here... There may be more info in there that is of use to you in your planning. https://www.small-cabin.com/forum/6_5643_0.html Final Words: Be Cautious with info provided on any site including youtube. There is a lot of Horse Twaddle peppered everywhere and it originates from a lot of misunderstanding & misinterpretations and people choosing to interpret things they want. I have seen a recent trend where folks give expensive poor advice to see if someone is gullible enough to do it and these people laugh when folks do, it is their way of getting their kicks... it is extremely distressing to see yet there it is. Well Drilling Clarity There are two methods used for drilling wells. Bore Drilling is faster but you have to go deeper because it does not fracture the rock in the drilling process. This type of drilling will cost more because you have to go deeper and they all charge by the foot. Cable Pounder Drilling is slower but it fractures the rock on the way down, these are most often shallower and have better water flow because the rock get's fractured allowing the water to flow faster. One side effect, is after the well is drilled there is a certain amount of sediment from the fracturing which usually is fully flushed within 6 months of use.

NovaDC Member	# Posted: 24 Jan 2023 01:48pm Reply Quoting: Steve_S Rain Water is NOT Potable Thank you, yes I do know this. I was meaning along with a robust filtration system. But just came into my head as I got a quote - not something I have seriously looked into and will probably still go the well route. Quoting: Steve_S Every region/area has rules as to what you can & cannot do Yes, fully aware of this and spoken to the inspectors at length. Quoting: Steve_S Be Cautious with info provided on any site including youtube I have been around long enough to know not to believe everything you read (or get told by an expert). I am the opposite of gullible. I check, recheck then check again before spending large amounts of money - so far it's worked very well. Quoting: Steve_S There are two methods used for drilling wells. Interesting you mention these. I actually have a rough quote from one of each (plus the $16k one I mentioned earlier). They both quoted between $7-8k (Canadian Dollars). Thank for all the inputs - I will add all of this information into the mix. From all of this - at the moment - I will stick with the plan for the RV power source with the understanding the generator will be needed a lot during the winter. Panels are the biggest problem but could look into some solutions for this - thinking I could have another angled array, plugged into the RV - within the limits of the MPPT. Panels are fairly inexpensive. Will be helped by well pump not being run off inverter. So, could have either small solar system (would require a DC pump) or generator (AC pump) to pump water into a tank - which I am thinking will have to be buried in the earth to keep from freezing. Then a small AC pump in the cabin to pump the water from the tank.

Brettny Member	# Posted: 24 Jan 2023 03:37pm Reply Quoting: NovaDC They both quoted between $7-8k (Canadian Dollars That's prety cheap for a well. It's not like throwing money out the window, it adds to the property value.

gcrank1 Member	# Posted: 24 Jan 2023 04:15pm Reply Our place is off-grid and dry, only 'recreational' but after cabineering this way since 1983 in two different places (both in south central WI, USA) we could live this way. Heat could be wood, but we have gone LP Utility water is diy filtered rain barrel Potable is local artesian well, tested and approved, hauled by us. We could also fill the 'jug' at the neighbor (Note that far more water is used for utility than potable and our daily water usage is faarrr less than the average per person in 'normal' living) Diy compost outdoor T No plumbing, we use simple 'washtubs', pee-bottle and night bucket for night/bad weather use, daily dump into, Greywater system, a simple French Drain The elec Ive described much of, but will add: Wire the cabin for at least 120vac, use an RV type plug outside to plug the gen-set into. Run the RV plug wiring to a small service panel inside and distribute your circuits from there. With it wired that way it wont care what you input 120vac with, gen or solar inverted. You get to choose what and when as time and funds allow. Ive had flat and angled rooftop array and ground mounts. Im not going to do roof again. Ime flat basically means you may get 25% of capacity in spring and fall, -0- in winter and maybe 75% with high summer sun on a good day. And a good day has about 4 good solar hrs in it......you Need enough array to completely recharge your 24hr daily use in that 4 hrs. So, it is far cheaper and easier to conserve energy than build a system to live like you do at home. That said, we do have plenty of led lights, usb ports, fans, an old combo tv/vcr, a small microwave, a toaster, a 30cup 1Kw old perc coffee pot as a 'water heater', a house sized upright vacuum,my old corded power tools including a 10" table saw and an old trailerhouse portable mini wash machine and thus far my little 40# 1700/2000 inv/gen runs all of it but not at the same time, of course. Not like we are living primitive. Now the kicker....last year I didnt even hook up the solar. Those LFP bats are so energy dense and by not trying to run the 'big stuff' that the gen is better at anyway, I didnt have to recharge the bats daily. I used just one at a time and rotated as needed, then recharged the low one at my leisure. Typically I topped up a 100ah bat in 2.5hrs with a 40a charger; Too Easy. Im thinking this year if I have the charger on the gen that if I only run the gen for 1/2 to 1 hr a day the bat-bank will stay pretty much topped. I Had to do that same thing with my orig agm bats but for more hours and it was marginal due to the slow absortion by the agm's.

DaveBell Moderator	# Posted: 25 Jan 2023 05:03am Reply Quoting: NovaDC I try not to post questions in general before I have done quite a bit of research already. Thank you.