Peak level of jealously...

Looking great!

I sure like your charging and electrical setup. I wish you put up links to the actual products and which one you used.
I was on Amazon pricing stuff according to your pics that I could find.

That stuff comes in lots of sizes so you might want a slightly smaller or larger unit than the ones I bought.  But…

Batteries are sok purchased from current connected.  Mine are just the plain 106ah not heated
https://www.currentconnected.com/product/sok-100/

Chargers are victron smartsolar mppt.  I have 2x 150/100 in the cabin and a 100/30 in the camper.   The 150 is how many volts it can take in from solar (eg I have three 48v panels in series so just under the 150 max) and the 100 is how many amps at 14v it can put out to the batteries.  They also have different models depending on what wire connectors you want to use.  So a link prob wouldn’t help much.  https://www.victronenergy.com/solar-charge-controllers/smartsolar-mppt-ve.can

Shunt is victron smartshunt.  I have 1000 amp version in cabin and 500a version in camper.  https://www.victronenergy.com/upload/documents/Datasheet-SmartShunt-EN.pdf

Inverter is AIMS picoglf  4000w 12v 240vs.  I understand it’s kind of a middle of the road brand not tier 1, but it was the only option I could find that would take in 12v and put out 240 split phase.  https://www.aimscorp.net/4000-Watt-12-Volt-Pure-Sine-Inverter-Charger-120-240.html

Victron and aims stuff purchased at invertersupply.  Their tech support has been helpful.  

The bus bars and switches are mostly bluesea marine stuff purchased from Amazon.  I have the 1000a bus bars at the battery and the 600a bus bars in the cabin.  They are smaller due to most of the load being AC when it gets to cabin.   I doubt I’ll ever have more than 100a at a time DC.
https://www.bluesea.com/products/1991/PowerBar_1000_-_12_3_8in_Terminal_Studs
https://www.bluesea.com/products/2107/PowerBar_600A_BusBar_-_Eight_3_8in-16_Studs__

Fuses are blue sea post fuses. I’m running a 125a fuse on every positive battery terminal.  And a 300a fuse on the 4/0 cable that runs from my battery box into the cabin.  
https://www.amazon.com/dp/B0019ZBTV4?tag=arfcom00-20

Cables are the extreme ones from batterycableusa

Inside the cabin the fuses from the bus bar are cheap chinese junk blade fuses. Here’s an example of one I used https://www.amazon.com/gp/aw/d/B09JNXX32M?psc=1&ref=ppx_pop_mob_b_asin_title

And here’s the fuse box I used as a DC distribution to go to all the lights and fans.  https://www.amazon.com/gp/aw/d/B07GBST5NX/ref=sspa_mb_hqp_detail_mobile_aax_0?ie=UTF8&psc=1&sp_csd=d2lkZ2V0TmFtZT1zcF9ocXBfcGhvbmVfc2hhcmVk

More pictures!

Electric stuff getting close to finished.  Still need to put roof and paint on to match cabin but got doors on the box.  Note main red switch in center disconnects all loads from batteries.  


Quick disconnect for solar panels on far side of box.  Anderson connectors.  You can also see one of two ground rods


Doors open. Note second main switch that disconnects chargers from batteries on far right above AC breaker box.


10 batteries. 12kw  Prob going to add ten more to other side.  


Close up of Pos post fuse block


This is the back of the main switch.  4/0 cable going from battery bus bar to switch as Input.  4/0 cable to inverter and  300a post fuse on 4/0 cable output to cabin.


Closeup of smartshunt.  Bottom is battery side 4/0 cable.  Top is 4/0 negative to cabin and 4/0 negative to inverter and the smaller 8ga wires are neg from solar chargers.  
The small red wire goes to Pos bus bar so it can monitor.
In background you see inverter DC connections and mppt on far wall.


This is the main solar switch. Input is two Pos wires from chargers.  Output to Pos bus bar.  


Cables from concrete box into cabin.  2x 120vac circuits from the breaker box. 1x 240v split phase orange from breaker box.  1 cable to replace the one the carpenter crimped through the wire insulation…. And the two 4/0 DC cables.   When we’re done they will be in a 2x4 raceway to discourage critters and crackheads from destroying it.  

Here’s where the electric comes inside to the 600a bus bars.  The bottom post in the close up goes to the 4/0 wire from the battery outside.  The other two go to fridge and the wire to the fuse box.  Can’t really see the fuses on these wires cause they’re tucked down a bit.  

And with the door closed, it’s tucked between fridge and bathroom barn door.  


Here’s the other panel by front door.  Light and fan switches built in. Weboost antenna below it.  


Inside that panel is the fuse box for all the small loads.


And the light switches


And the weboost unit


And the flooring is done…


And the rolling ladder to loft so I can slide it back and forth to better use space when I’m in kitchen or reloading stations

It won't be long and y'all can move in.

Electric shitter adventures have commenced…



Hooked up to 240 split phase, ran first test.  For purposes of testing they have you put 1m of tp and 1.2 liters of water in it and start the incineration cycle.  It should last 60-80 min at 2000w.  If it goes above 90 min it indicates poor airflow and improper vent install.   First test, 94 min.  So I go inspect contractor work and sure enough it’s like they didn’t even read the manual.  pretty sure i know what's wrong (since there's a giant ! in the manual that says don't do x, and they did x)  I'll prob fix it tomorrow and run another test.

If it had worked it should be 170ah or so or 17% of my battery capacity.  Since it ran 94 min AND more than the rated 2000w, I was down to 74% when it finally ended.  and their sales chick said it would usually only run 45 min instead of 60, so i was kind of basing my electric budget on that, but maybe they have tiny canadian turns instead of midwestern corn fed turds.  seriously though, i am hoping the test load of 1.2 liters of water was more of a stress test and not indicative of average duration.

On the positive side, inverter handled 2500w for 90min like a champ and didn’t even get warm.  

I turned off the solar so it wouldn’t interfere with the test.  Roasting turds on a sunny day would prob only use about 5%.  But at night in the winter…. No Brazilian steakhouses or taco bell.  I've been thinking about adding 4-6 batteries.  With current budget, I'm using around 800ah per day, so 80% of battery, and that includes 2x "flushes".  No worries as long as I get sun.  But I'm thinking 6 batteries would give me 2 days of no sun.   I could however, cut my usage considerably if needed.


Porch lights look good.  Can’t wait to clean the construction junk off the porch

I think I’d have a back up compost outhouse just in case of beer and beans night.

I like the porch pic.

Have you thought about going Lithium batteries. We use them in our cabin and I really like the full discharge ability. Only draw back (beside price but that has dropped a lot in the last 2 years) is no charging below 32 deg, but the Victron has the ability to add ( if you don't have already) a temp probe. I set ours at 40 deg just to be safe. We have 2x 24v 100 amp units and 3x 200w 24v panels will keep them topped of good unless we need the a/c. Then I just run genny during the day and use batteries at night.

We have a window a/c unit that is not very efficient so this winter/ spring I am going to install a split system. Helps in the 90 deg N.C. summers, lol.  I think we will just still use our wall propane heater ( it also hooked to my outdoor cook stove) for heat but nice to have a easy back up.

I had fun fitting up our cabin, and still like to "piddle around" with things. Wife tells me to relax but the projects are my relaxation, lol.

More random thoughts of stuff I did:

I made our bed stand. Built out of 2x6 pine to fit a queen bed. I made it tall enough that totes fit under it. the totes act as our "luggage". Wife and I each have 1 or 2 and pack the full at home, put in bed of truck, then under bed in cabin. I made a bookcase headed board for it later.

Attached File


We need to sleep 4- wife and I, my mom, and one more adult. But wanted to have room to move around. So we have a futon couch and then I got a single murphy bed frame kit. It works good to get room during the day but extra sleeping space at night
Attached File

Attached File


Don't have photo, but I made my kitchen outside on out porch. That keeps heat out in summer and also frees up space inside.

I do actually have a backup toilet.  PETT bag style I’ve been using in the camper since 2016.  


The batteries are LiFePo4 chemistry.  And yes You can see the victron batterysense blue square box in some of the pics, which sends temp and other data to the chargers via Bluetooth.  

The folding bed is a good idea.  Didn’t think about that.  Was just thinking futon but may look into those

Couple quick pics of lights in bathroom, roof and doors on the electric and plumbing sheds and a view of the plumbing pump, pressure tank, and water heater all connected and pex run inside to shower and sink.  Almost finished running drains out.  Put another fuse box in there for pump and water heater.  Will add heat tape to it soon.  And I still need to run propane in there.  

Been a bit OP. How are things progressing?

Still watching quietly over here in the corner, this is essetially exactly what I'd like to do on a quiet lake property except for super insulated everything.

Going great!

Office / dining room is almost done.  Built table today.  I’m going to print a topo map 4’x3’ and put it in the table and cover it with acrylic or glass.


Got windows put in loft and picture window in the shower lol.  The bedroom window hinges open from the top.  The shower window is fixed.






Next week I’ll install diesel air heater and run the heat tape around the plumbing.  
Last two major things to do are finish shower and put in kitchen and counters.  And eventually get a wood stove installed.  

I’ve got the shower and sink plumbing done and the pump and pressure tank etc.  my plan on the shower is to line the walls with copper sheet.  I’ve got about $1800 in copper sheet. Just trying to figure out how do to the breaks.  And I’m planning to drop the floor and make a fiberglass shower pan below the level then put a spa style teak slat cover over it flush with floor.  The copper will be kinda bright at first but over time as it gets a patina it should work pretty well.  I’m also playing with tung oil to see how light I can keep the walls.

Looks awesome OP.

Glad I got tank overflow plumbed lol.  We will prob get enough rain yesterday and today to put 900 gal in my 1100 gal tank which was already full.

I definitely need to add more batteries if I was going to live full time in it.

I was wondering how much rain you might get from the storm.

Prob not nearly as much as the NC side.  Steady all night and weather said we got 2” yesterday expecting another inch today

Had a few nights below freezing.  27* currently.  I got the heat tape installed just in time.  

Took some screenshots.  The first one is from the victron battery sense unit stuck to one of my batteries.  The blue line shows battery temp which drops to 4 Celsius but never freezing.  That’s good.  Both the battery and chargers have temp cut offs to prevent anything bad from happening.  Still I’d like to keep them above freezing if possible.  



The next two are from my smartshunt.  You can see in the bottom one what the typical daily cycle looks like.  The blue line is % of charge and red line is flow of amps.   Positive value means current is flowing from chargers into the battery.  Negative means loads are drawing the battery down.  

Basically this is what I think of as my resting load.  Not really using anything in the cabin.  Just the fridge, inverter and heat tape.  Some other minor devices are always on and drawing current as well.  Adds up to about 15a at 12.8v dc.  
Occasionally I nuke a turd or charge a laptop or something but the daily pattern is quite clear.  

You can see the constant slope of the blue line. It’s flat when the sun is out and then drops in evening and overnight.  
Note how quickly the solar charges the batteries back to full in the morning then just floats all day.  

Another point of interest is the peak of the red line.  You can tell which days are cloudy and which are sunny.  In fact I selected the days in the first graph to show the four days of dense cloud cover we had as the hurricane came through.  I think we got about 3” of rain.  


On the second chart you can see the last day is yesterday. Our first freezing night.  This was the first day I turned on the heat tape and you can see the slope on the last blue line is steeper than normal.   Combine that with clouds the day before and it drops fast.  


one last point, the sun is much lower now and i haven't adjusted my solar panels yet.  i need to do that soon, but really, clouds make the real difference.

this is why i think i need to double my battery size.  i can charge it back up pretty fast with my 2700w of solar.   but my 1000ah of 12v battery really wouldn't last 5 days of clouds.  2000ah would do a lot better i think.     of course, if needed, i can always conserve power by dimming the lights, turning off the inverter (toilet is only thing that needs AC, as everything else is DC).

I gotta come back and read this entire thread; so maybe you’ve answered it.

But what kind of lifespan are you expecting out of the batteries as they have a pretty high replacement cost.

they're rated for 4000-8000 cycles.    that's 22 years if i cycle it once a day, but really, i'm only cycling about 15% of it.

Awesome post OP

I have a property that is low (next to a river).

I would like to know more about what you are doing with septic - gray and black water?

I would also like to know more about your rain water collection system - is that potable?

Thanks,

Red

I don’t have any black water.  I use an incinerator toilet that turns all human waste to a little bit of ash.  

The rain water collection is literally normal gutters with downspout going into a large tank with a couple filters.  If I drained the tank I can lift it myself but it would prob rupture if you tried to move it with water in it.

Would love to have some more information on your toilet - Brand - model etc.

How are you showering and washing dishes?

Awesome post BTW OP!

Red

https://www.cinderellaeco.com/us-en

They have two main models.  One runs on 240v ac and the other runs on propane.  

Mine is the electric version which they say you can’t run on solar but I did it anyway.   It would have been easier for me to run on propane but I am mostly building this cabin to be sustainable and I don’t want to depend on propane if shtf.

Op is living my dream

soon...  

i've been dreaming of this for decades.  wish i could have afforded to do it in Idaho/Montana, but I think TN is really a better fit for me.


btw, on fb and reddit there are lots of groups with 50k to 400k members focused on offgrid living, shed-to-cabins, tiny houses and the like.  it's really fascinating to see how many people are living the old ways.   My primary goal is to keep as many modern comforts and capabilities as possible if the world goes to hell.   However, I'd say 90% of the crowd are into it due to affordability and varying degrees of being anti-social.    and a shocking number are in what i consider the arctic circle, which should be drawn along the southern PA border.  lots in canada and AK.  so there's lots of composting toilets and build quality of 1930s Appalachia.     and so many doing this with 2-4 kids, minimal plumbing, and very minimal electricity.  

i really hoped to get a lot of good info from sustainability and permaculture groups, but dang, it's like those people are all talk and never do anything.

Can you point me towards those groups?  I just bought 18 acres 80 miles north east of fairbanks. 6 miles off the road(can drive a truck to it in the summer).

Gonna build a cabin and strongly considering just saying fuck society and living there year round.

Big question I haven’t found the answer to is health insurance tho.

I can easily pay for a once a month trip to town to get supplies or what not. But not if I’m paying $1200 a month for private health insurance or something.

Just go to either site and search for offgrid or the other terms.

Gratuitous leaf pic out the south window

This is the topo map I intend to put on my table.  My original intention was to pour epoxy on it but option two is just to lay a single pane of glass on it.  


Any advice on how hard pouring epoxy is to prevent it from being cloudy etc? I made very sure the table was mounted precisely level so it wouldn’t drip over one edge.  But I have zero experience with this and only one shot.

I would cover it with a piece of plexiglass.   It's cheap and easy, and if it gets messed up you can replace it.   It is less likely to break than glass, and easier to apply than epoxy.

You are going to want an edge to keep the epoxy on the table. It will run off, no matter how level you have it.

wish i'd thought about plexiglass.  duh.  ordered some glass last night and i'm going to pick it up in the morning.  if it doesn't work i'll try that.

if you scroll way back up to like post 18 or so, you'll see a pic showing edge.  it's hard to see from pic but edge trim is 1/4" higher than the plywood

My dad did a table top with a map on it at his old house at Edisto Island.  He built the table with a maple edge that stuck up enough so the plexi was flush with it.  He was able to drill and countersink holes in the plexi and used brass screws to attach the plexi to the plywood table top.  It came out looking nice.  Since the house was a vacation rental during the summers, the plexi got beat up every few years and he just replaced it with new from the hardware store.

Epoxy is not too hard to do. Use a heat gun to get the bubbles to float up. Something like paper might be better to do a seal coat- it will try to float up. I did my bar and it came out great. A edge does help. Look for one that is UV stable. Plexi is okay- can scratch easy depending on the type. Glass is good but can break easy if hit just right. But both let you change whats under it- Epoxy not so much.

Interesting how the ONLY criticism anyone has for this cabin is the choice of what to put over a map on a table.  That says a lot about how cool the cabin is.

Table turned out nice


But definitely need either a lot more heat tape or a pad to keep batteries above freezing.  Dang.  

Prob need to do a lot more for the plumbing too

Looks good man!

Hey OP.  Awesome thread!

I'm going to bookmark this one.  Working on one of my own in South MO near Arkansas border.   Having to work on it all the time really does start to drag but we are making steady progress.  I'm still trying to work out exactly where I want the lighting and water lines but we are doing it very similar.  Rainwater collection, shallow pump and filters, composting toilet, 10KW battery with 2KW solar (next year) and a 5.6KW generator.  Using one of the EG4 6500W inverters.  Ours is a bit larger but still small-ish at around 650 square feet.

You've done some really nice work man.  Keep the updates coming!

Oh I LOVE that!!!!  I'm stealing that idea!

Thanks! They’re a pain to deal with now but mytopo will print custom maps of whatever area you want.    If you zoom way in and look near top right in the white space you’ll see a diagram that shows how this map overlays 4 different usgs quads.   I really wanted to make it bigger then cut it to orient true north exactly aligned with north on the map but the interesting areas locally are more left and right than up and down so I just left it as is and made the table 3’x4’ to fit the map size.  You can order bigger though.


I would have done a slightly larger cabin if I’d had more room but on the top of the ridge I really just don’t have the space on a narrow ridge top that drops off 45* on either side

Are you running your water through a UV light?

I am all rain water for domestic.  Three filters and a UV light.  Wife hates all other water now.  

This has been a totally shit year for rain and last half of last year was pretty bad too.  I still have 6800 gallons out of 20k.  4500 sq ft of roof.

haven't decided but probably yes for drinking, no for shower/sink.    for drinking water, i bought a zero filter dispenser which i'll keep in fridge, and i have a couple steripens so i'll prob just fill the zero from sink, let it filter, then nuke it with the steripen

so this is the insulation i got done before it got cold.  it worked fine when temps were dipping into the teens overnight etc, but clearly it wasn't going to stand up to the deep freezing going on at the moment where it was 0* and -2* and I think the high today will be 14.   anyways i tried to drop a gallon milk jug of boiling water in yesterday but the portal was frozen so i just poured it into the drain hole.  today i took a couple jugs and used one to thaw the portal.  there was about an inch of ice on the top, but nothing was broken.   i hammered a hole in the ice and dropped a jug of near boiling water in.   i doubt it will accomplish anything but i'll go check it again tomorrow.   it will be monday before it gets to 32 and the high is only 36 monday.

so anyways, i'm soliciting thoughts on my current plan.   i have a propane instant hot water heater in the box with the plumbing.   i'm going to insert a T in the pex and a valve and run a line of pex back into the top of the tank.    the idea being if i open the valve, water will flow through the heater and it will start heating.   the pump will pull water from the bottom of the tank and push it through the water heater and back into the top of the tank.       the pump isn't really rated for continuous.  maybe i should get one.  but i should be able to run 15 min at about 40-60 psi.  

The heater is min/max 20k/42k btu/hr.   so if i run 15 min that's a min of 5k btu and maybe 10.5k btu put into the tank.     it's an 1100 gal tank but i really just need to keep the top layer from freezing not warm the whole tank so i'm not sure how to calculate if 5-10k btu would do that.






eta: i think 9k BTU would raise the entire tank 1 degree in 1 hour.  

I think your math is right, 9k btu to raise the temp 1 deg F.

I believe the question here is your heater will put X number of BTUs/hr into the tank, and the environment will take out Y number of BTU/hr.  Bigger temperature difference will lead to a bigger Y; at what temperature difference (32-ambient) and other environmental factors, like wind, will Y>=X?

Newton's law of cooling (https://en.wikipedia.org/wiki/Newton's_law_of_cooling) could give you the answer, but you need to do some estimation of the heat transfer coefficient.  Maybe measuring the water temp and ambient air temp right as the sun sets, then a couple hours later, will give you enough info to do an approximation.