Going completely off-grid in Montana - I have questions.

[t.hinckley]

I read through the thread from mecdatlanta and was able to get a lot of information from that, but still have some questions. I will try to list them out here but will more than likely add more as we go along.



Here is the situation:

• My wife and I are in the process of buying 160 acres in Montana near Drummond/Missoula
  • Property is “ridge to ridge” of a valley that runs north/south. Build site is west facing with good southern exposure

Build site is the small square just right of center

• We are 4.5 miles from the grid so that is not an option
• This will be a permanent home for just the two of us, we both work from home so Skylink will be a must
• We have approximately 2 years (summer/fall 2026) to have everything built before we are ready to move (last kid goes off to college)
• I am pretty handy, but not with electrical much more than end wiring, I am better with a hammer and nail gun. This will not be a DIY install, but will be DIY maintained
• Because of the build site, the home will have a walk-out basement, but primarily main floor living
• House will be designed for efficiency. Walls will be minimum of 2x6 plates with offset 2x4 at 24” on center

From that, we are at a blank slate.
Looking at a Walipini Greenhouse for veggies.
Geothermal Heat pumps for HVAC
Wood stoves/fireplaces for backup heat in the winter
@robbob2112 I want to hear more about your power container, have you done any plan drawing for it?
Will probably start with a small (12x20) studio cabin which will become a guest cabin after the main house is built.
Investigations show we will need about a 500' well, but it will be within a few hundred feet of the house
Eventually we will also add a shop/garage and a 2nd guest cabin/tiny home
Trying to get the house down to about 3k square feet - Master suite, guest suite, two bedroom/offices, and a "bunk room" for eventual grand kids

Some of the questions I have, and remember I am as new and naive in this area as an infant.
1 - Extra power, what do you do with it? What sort of considerations are there? Isn't their risk to all of the components from "over charge"?
2 - Any reason I can't use back to back chimney's as "thermal mass" in the center of the house?
3 - Trying to determine potential load is a challenge. Too many variables from current grid use to really have good answers. Suggestions and recommendations for efficient appliances appreciated.
4 - What questions do I need to ask a potential contractor? What hardware should I make sure we are steering clear of?
5 - Because of the views, looking at lots of windows, am I wasting money going with the above-mentioned wall design?

 

[Mattb4]

1. You may have extra generation capacity at times but you only use as much as you have loads to use it on. A lot of us on Off grid solar try to figure additional loads during times where we could power them. Mostly because it seems a waste to have all that "potential" electrical goodness not being used. You batteries charge is controlled by the SCC or other chargers. If they are working correctly they will not overcharge.
2. No reason that I know of. Be aware that a lot of nonsense about Thermal mass and home heating is out there. Thermal masses do not create additional BTU's. They just slow down heat transfer.
3. Yes it is a challenge to figure up all your loads. It also becomes a challenge on how to manage them ( see #1) to take advantage of when power might be available. Appliances may or may not be economical buying the most efficient. It also is another game of adding up the plusses and minuses.
4. Dealing with contractors in a remote location like Montana rural land is going to be tough. The majority of them will simply not return your calls or say no. The few that might work with you you need to be extra careful that they are scammers.
5. Windows are holes to the outside. The best of them with the highest possible ratings (U) are virtually nothing for insulation value (R). Plan to cover them during periods of extreme weather.

 

[yodamota]

2. Have you looked at rocket mass heaters? Here is just one movie on them. https://permies.com/s/wbfy967

 

[jvierstra]

For heat, look at a high mass wood burning Russian stove or a rocket mass (as said above). We have a small home (~1200 sq), but one can centrally locate stove in a larger home. We do 2 fires a day when below zero (the house is at the latitude of Finland) in a SIP (stuctural insulated panel) house and keeps it nice and warm (should note that ~60% of the walls are windows). It radiates heat for 6-8 hours even after fire is out. You can also put a serpentine in the mass to distribute the heat with hydronic radiators. Look at this website for examples: https://www.firespeaking.com/portfolio/. We covered our stove with adobe made from a clay deposit on our land and horse hair.

 

[newbostonconst]

ICF.....I can go 5 months a year without heating or cooling the house in spring and summer in Michigan (thermal mass works when the outside temp goes above and below the inside temp by 10 degree). We have 3700 sqft ranch walkout with 78 panels (~25kw) (~18kw in a solar fence config 60 degrees..to get winter solar to heat house) Hoping this year to be able to make it through winter with no utility use) We use 25kwh a day on normal stuff and rest goes to heating/cooling...we live comfortly....Geo for heating and cooling....

 

[green mountain boys]

I have heated solely with wood for the last 45 years and I live in a cold climate. The biggest problem with wood is figuring out how to create a steady supply of heat. So, you either are constantly tending the fire to maintain the desired heat output, OR, you need a thermal mass to buffer the heat output of the fire. The best two options I have found are:
1. WATER, like in an outdoor wood boiler (indoor units also available)
2. Stone/brick. Many options available. For example: https://tempcast.com/

I am about to begin my 30th year with the same outdoor wood boiler. I have a 500 gallon water storage buffer for my heat is always available and always constant even if the fire goes out.

 

[OzSolar]

I am pretty handy, but not with electrical much more than end wiring, I am better with a hammer and nail gun. This will not be a DIY install, but will be DIY maintained

Sounds like a great thing you're getting ready to/are able to do!

I am electrician that helped a few folks build off grid the 30 plus years. One of my big take aways was that being your own utility is a pretty serious undertaking on many levels.

4.5 miles from power? How far is the fire department? A paved road?

Picture your system going down during a big snowfall or ice storm and your contractor can't get to you. Even if they can get to you it may not be that day and there's just not that many folks who do off grid systems. What if your guy is on vacation on another continent. It may solely be up to you figure out the issue.

I'd really steer you towards being very integral to the installation and set up of your system.

Not trying to talk you out of anything just offering you some things to think about.

 

[shazam]

ICF.....I can go 5 months a year without heating or cooling the house in spring and summer in Michigan (thermal mass works when the outside temp goes above and below the inside temp by 10 degree). We have 3700 sqft ranch walkout with 78 panels (~25kw) (~18kw in a solar fence config 60 degrees..to get winter solar to heat house) Hoping this year to be able to make it through winter with no utility use) We use 25kwh a day on normal stuff and rest goes to heating/cooling...we live comfortly....Geo for heating and cooling....

What he said^^^^^ ICF all the way! Same situation for us in Northern Ohio. Highly recommended!

 

[robbob2112]

@robbob2112 I want to hear more about your power container, have you done any plan drawing for it?

Still just back of the napkin/mind sort of thing - there is a thread around about the ultimate fireproof room that has about as detailed as I have gotten.

 

[t.hinckley]

4.5 miles from power? How far is the fire department? A paved road?

The road is the nearest power, no clue where the nearest fire department is. I am planning on external fire suppression sprinklers, figure that is the only way I will be able to get insured living in the woods.

I am 100% not a "fire and forget" kind of guy. I will be all over the contractor doing the work, not to make sure he is doing it right (how would I know), but to make sure I understand what he is doing.

ICF

What is ICF?

Still just back of the napkin/mind sort of thing - there is a thread around about the ultimate fireproof room that has about as detailed as I have gotten.

I'm pretty handy with off-the-shelf/online drafting tools... Mind if I pick your brain more? The bit I read in the other thread just tickled that "This is what you want" bone...

 

[t.hinckley]

I actually went and walked more of the property today with a guy I hired to find out where and how deep water is (90% success rate). He convinced me to move the build site further up the hill, rather than accessing the house from the main road we would go through the property, back down the east side, then cut back north to get to the house.


This was an area we couldn't get to with the rental car (encroaching trees that can be trimmed once we own the place). Better views and better solar potential, less steep driveway. It moved the build site up the hill a couple hundred yards. What is the opinion/consensus on tracking panels?

Actually, as what usually happens when you get an ex-marine (him) and an ex-army grunt (me) we may have hiked/climbed/trekked a lot more of the property than was planned, or based on the way my body is feeling, wise...

 

[robbob2112]

The road is the nearest power, no clue where the nearest fire department is. I am planning on external fire suppression sprinklers, figure that is the only way I will be able to get insured living in the woods.

I am 100% not a "fire and forget" kind of guy. I will be all over the contractor doing the work, not to make sure he is doing it right (how would I know), but to make sure I understand what he is doing.

What is ICF?


I'm pretty handy with off-the-shelf/online drafting tools... Mind if I pick your brain more? The bit I read in the other thread just tickled that "This is what you want" bone...

Pick away

 

[robbob2112]

What is the opinion/consensus on tracking panels?

In general panels are cheap enough it is better to put in another string for less money than tracker. Trackers are great if you have a limited footprint and can't roof mount.

Most folks that do their own ground mount have the ability to adjust tilt when needed.

 

[Mkgough]

Solar trackers for your panels, easy to clean and get snow off and you can park them at sharp angles to let snow slough off. A tracker is only $500 for 1200w of very efficient solar compared to any other method. I have 2 and the way to go, but I am in hot Texas, but will be adding them to my cabin property at 8500 ft so I can tilt them for snow slide. 8’ diameter of space needed for each one. I can charge 6000w of batteries per day with each one. I also have solar EG4 mini-splits that run on them as well. One will easily drive a 12k btu mini, prob even 24k would work based on 800w min for 24k since they track so well.

 

[Rocketman]

Don’t discount wild land fires…

Consider having the outside layers of your house all non-flammable. And a large firebreak.

We are touring Alaska and I stopped by someone’s home for a windshield rockchip. He told me no problem bringing your Motorhome in. He had about 30’ all around his house a driveway of crushed rock. It wasn’t until later that it dawned on me that was his wild fire break.

 

[robbob2112]

Solar trackers for your panels, easy to clean and get snow off and you can park them at sharp angles to let snow slough off. A tracker is only $500 for 1200w of very efficient solar compared to any other method. I have 2 and the way to go, but I am in hot Texas, but will be adding them to my cabin property at 8500 ft so I can tilt them for snow slide. 8’ diameter of space needed for each one. I can charge 6000w of batteries per day with each one. I also have solar EG4 mini-splits that run on them as well. One will easily drive a 12k btu mini, prob even 24k would work based on 800w min for 24k since they track so well.

How deep does the post need to be and what wind load does it work for? Maybe I am hasty. I live near Blackhawk CO at 9100ft. Bedrock is about 48in deep and the wind speeds I have tracked get as high as 110mps. Average is more like 5 to 10mph, but frequently dawn to dawn+2hrs hits 50MPH gusts.

 

[MattiFin]

Solar trackers for your panels, easy to clean and get snow off and you can park them at sharp angles to let snow slough off. A tracker is only $500 for 1200w of very efficient solar compared to any other method.

On the other hand with $500 you can get 4kW of extra panels. At least if you don't need to pay the US import(extort) tax.

 

[newbostonconst]

What is ICF?

Insulated Concrete Forms: Pros and Cons - Jenkins Design Build

Are you thinking about using insulated concrete forms (ICF) to build your new home? We'll cover what ICF is, how it works, and the pros and cons of ICF

newhousebuilder.com

Ann arbor new house build

484 new items · Album by Kevin Finamore

goo.gl

 

[t.hinckley]

Don’t discount wild land fires…

Consider having the outside layers of your house all non-flammable. And a large firebreak.

We are touring Alaska and I stopped by someone’s home for a windshield rockchip. He told me no problem bringing your Motorhome in. He had about 30’ all around his house a driveway of crushed rock. It wasn’t until later that it dawned on me that was his wild fire break.

well ahead of you on that front.

 

[Johneb]

Just a thought. Since you are going to be out in the sticks, I would go individual components (inverter, scc, etc….) with extras you can swap out if need be. Also might consider something like the Outback inverters. They are more expensive but built to go decades.

 

[Mkgough]

Insulated Concrete Forms: Pros and Cons - Jenkins Design Build

Are you thinking about using insulated concrete forms (ICF) to build your new home? We'll cover what ICF is, how it works, and the pros and cons of ICF

newhousebuilder.com

Ann arbor new house build

484 new items · Album by Kevin Finamore

goo.gl

Also called Fox Blocks in the US, my brother-in-law used them to build a home in Wyoming.

 

[IGBT]

What about taking advantage of the slopes and making some sort of berm home, still with the concrete, but seems like it would really help with moderating temperatures. There is a reason pipes that are buried 4 feet deep don't freeze in winter...

 

[t.hinckley]

making some sort of berm home

Views/Windows.

 

[jvierstra]

Look up SIPs. No framing involved. House is CNC cut at factory and shipped. We roughed in a 1000sq custom house in 1 week with roof and is r45 walls and r60 roof with no thermal breaks like studs. Front windows are 9 ft tall. Build roof at optimal angle for solar (your latitude - 21degs). Sips are not common but used in other countries extensively but catching on. US is typically pretty far behind in SOTA building technologies.

 

[Chispas]

2. Have you looked at rocket mass heaters? Here is just one movie on them. https://permies.com/s/wbfy967

For a comprehensive look at RMH tech try batchrocket.eu .