Off grid new house build.

[JayArr]

We've purchased our retirement land and are going to build a house in the country then sell the house in the city.

We've got problems with getting the grid to our lot since easements are required from every property along the route and some of the owners are incommunicado and others want large cash payments in order to sign. I'm trying to compare apples to apples by extrapolating each scenario out by 15 years and measure the total cost of power.

I'll have a huge south facing sloped roof for panels so I thought I'd look into off-grid. I'm familiar with inverters and charge controllers from my RV but have no experience in the whole house hardware.

I use a LOT of power so I'm curious as to whether I can make this work. I'm currently using 70-80 kWh per day because both my wife and I work from home and I run an electronics repair shop from here. On the weekend I either work on cars, do some welding or build something in the wood shop.

I'm thinking I need a big genny to run on the weekends when I'm using high power machines like welders, compressors and saws. I'll need a small solar system to keep the lights on and the internet running in the utility building and then there is the house. It'll be small, about 1500sqft and the stove, water heater and dryer will all run on LPG. Heating will be by LPG in floor radiant heat with a wood stove in the living room. I hope the same genny can serve as backup and or battery charge when sunlight is not enough.

For a first step I've ordered a power analyzer to go on my breaker panel and monitor and record what each branch uses, when it uses it and for how long. I've really got to get a grip on where I'm using so much power. I'm thinking I need to somehow cut it in half at the new place. 35kWh per day? We'll be retired so that should help.

I'll be in and out of there asking questions about how to do things and such, I hope I've picked a friendly forum to join.

JayArr

 

[Rednecktek]

Blurb time!

Well, I'll start the default answer to these questions and we can work from there. Here's you To-Do list:

1: Power audit! This will give you some important information on how big your inverter needs to be as well as how much battery capacity you'll need. There is a link in the FAQ section (I think, or someone here will post it shortly) so fill in the blanks and see what it comes up with. You'll probably need some sort of Kill-A-Watt to get accurate measurements. Are you going to be running a 12v system? 24v system? 48v system? What are the specs on your solar panels? VoC? Vmp? Being as this is a new build, throw together a wish list of what you want and estimate on the high side.

1a: Where do you live? Speccing out a system for Scotland is a LOT different numbers than Arizona due to the amount of light you actually get. Someone here can post the link to the PVwatts.com or JCR Solar Uber-Sun-Hours calculator sites to help figure out how much you'll have to work with. That will be a box in the Power Audit form.

2: Parts list: You don't need a make & model list, just a parts list to start from for reference. You'll need an inverter, a MPPT charge controller, fuses, shunt, buck converter, batteries, wire, etc. Once you have a basic list it can be fine tuned to make & models after that. If you're looking at the All-In-Ones check for correct voltage outputs (120v or 240v Split Phase for North America, 220v Single Phase for European type areas) and make sure it has enough capacity for a little bit of growth and fudge factor.

3: Budget!: Steak is great but doesn't mean anything if your wallet says hamburger. Figure out what you're able to spend now vs what you'll have to cheap out on now and upgrade later.

4: Tape measure! Figure out where you're going to stick all the stuff you'll need. A dozen 3000AH batteries sounds great until you're sleeping on the floor because there's no room left for a bed. Is there a compartment that can house all this stuff? Will the server rack batteries fit? Are you going to have to make space? Physics can be pretty unforgiving.

5: Pencil out what you think you need and throw it at us so we can tell you what you've missed (because we ALL miss stuff the first go-round ) and help figure out which parts and pieces you're going to want to get.

Well that's the thing about solar systems, there is no 1-Size-Fits-All answer. Your system will need to be designed to fit YOUR needs. When you design and built the system, it's not going to be the perfect system for me, or Will or 12vInstall or anyone else, but it Will be the right system for You and that's the goal.

As for where to get started, let me throw my standard blurb in here to help point you in the right direction. There's going to be a lot of math and research involved, but that's going to be a LOT cheaper than just buying parts off of someone's list and finding out that it doesn't do what you need.

Don't panic on the Power Audit, you'll actually be doing that a few times. When you do the first pass put in ALL the Things that you might want. AirCon? Sure. Jacuzzi? Why not. MargaritaMaster-9000? Go for it.

The second pass will be the "I Absolutely Need This To Survive" list that isn't going to have much on there.

The third pass will be the "This is what is realistic" audit that you'll use to design the rest of the system.

The Power Audit is going to tell you 3 primary things: 1: How big does your inverter need to be to power your loads? 2: How much battery bank do you need to last $N number of days with krappy weather? and 3: How much solar panel will I need to install to refill those batteries in a 4 hour day (the average usable sun hours rule-of-thumb).

Once you know what you Want and what you Need and what your budget can Afford there will be somewhere in that Venn diagram where those three things meet.

After that, THEN you can start looking at parts.

Yes, it's a long drawn out process, but it's worth it in the end. Not every house has the exact same floorplan, not every vehicle is the same make & model, and not every solar system is designed the same.

 

[DIYrich]

From your profile, I am guessing you are near Vancouver, British Columbia, Canada. Check out solar and other energy efficiency incentives in your area.

How much land do you have? If a lot, I would consider:

1) Diesel generator for off grid use. Much longer lasting. With home delivery for off road use, you can save on the gas tax for the diesel.
2) Geothermal heating and cooling. Can also help with hot water. Can have a diesel boiler (home heating oil) as backup heating.
3) Induction stove top for cooking. Electric oven.
4) heat pump type clothes dryer (Miele is a good brand).
5) now that you are all electric, solar and batteries. Ground mount the solar for optimal orientation, easy maintenance, and snow removal.
6) for batteries: have a separate building (think heated garage) to house them for safety (fire risk).

All that is expensive, but can have payback in the 10-15 year range. 70-80 kWh is about 2-3 times the size of a typical home. Wild guess: 25 kWh of solar, 100 kWh of LiFePO4 batteries, and 2 or 3 Sol-ark 15k inverters in parallel (you may be able to have a 3 phase system for your shop equipment). With a generator, you can downsize the system. The batteries will also let you downsize the generator (enough kW to recharge batteries, and supplement for peak loads - maybe 10 to 20 kw?). 5-10 hour run during peak usage times to supplement and recharge. The larger the solar, the less fuel you need for the generator.

 

[DIYrich]

How much is the estimate to run electricity to your house? If you are talking running wire across multiple properties, are you talking 0.5 to 1.0 miles? That is $20,000 to $80,000 USD depending, without the cost of easements.

If you can ground mount, it is easily expandable. Start on the small side. See if you want more batteries and or panels for extended cloudy weather in winter.

 

[Mattb4]

We've purchased our retirement land and are going to build a house in the country then sell the house in the city.

...

Pardon me but I think you did not buy with all your needs in mind. Through the years I have seen many people buy rural undeveloped property based on visual desirability and not whether it is develop-able for their intended goals. Sometimes that is a factor of cost but it also can be real limitations like the ability to get year around services such as utilities and access. Eventually once the reality of it all sets in these properties go back up for sale. There is a reason that rural property that has been developed into actual livable homesteads draw a premium price over just rural land. Also rural land that already has access to utility power fetches a higher price.

That said many people do start off and put the blood, money sweat and tears into taking a raw piece of land and making it into their dream. During the process compromises and workarounds are going to happen. Take for instance your needs for working at home. Perhaps you could look into renting/leasing space in a local town that has utility power?

I think you will need to sharply curtail your energy needs from what you are using presently in order to come up with a viable solar power solution. Especially so since your location seems to be British Columbia, Canada. A palce which is not known for lots of sunshine.

 

[Bluedog225]

Welcome. Sitting this morning in my rural cabin without easy grid access.

My strongest recommendation would be a thorough site plan. And a real budget based on actual estimates. Off the top of my head (for me):

Solar, batteries, etc-$25,000 (yours=higher)
Septic-$20,000 (yours prob lower)
Well-$20,000
Road-$12,000-road base, not paved

Do-able but expensive. I came out of retirement to fund. May be no prob for you but best to avoid surprises.

Roof top is very appealing but serious installation hurdles, fire risk, and maintenance issues. Enphase microinverters mitigate the fire risk. Nice but spendy.

All the best.

 

[JayArr]

Thanks for all the replies and advice. It reassures me that I've found the right forum to join.

Corrections:

Yes, I live in BC Canada but the land is in Nova Scotia. One site I visited said I will get 1090 equivalent hours of sunshine per year.

The problem with the grid isn't the cost so much as the legal problem of not haveing the easements required from other landowners to tun the distribution line to the end of the road where I am. I'm not completely blocked, I could pay off one landowner and get power to my lot for about $40k. Then I get to pay a power bill every month. I think if I look at total cost over a 15 year span a solar system may be the better way to go.

The lot is 4 acres on the ocean at St Mary's Bay with the most incredible sunsets. This land is well worth the effort to develop.

I figured I would need an audit of some sort so I ordered a 16 channel power monitor from Amazon, it has current clamps that go on the branch wires at the fusebox and measure/monitor/log what every outlet in the house is usung and when. This may take couple of weeks but I hope to be able to differntiate between household, home business and weekend hobby power requirements.

At the new location I'll have a small house and up the slope a couple hundred feet will be a very large utility building that will have my woodworking, electronics shop and automotive shop. My wife finally gets a house that is just a house and I get the mother of all man caves. This could help or hinder the design, The utility building may need minimal power when I'm not there, it's unheated and has no plumbing. I thought I'd put the diesel genny up there and run it when I wanted to work with the big machines. This would mean the solar only needs to be scaled for the house.

I'll start with the audit.

Thanks!

 

[Danke]

 

[Bluedog225]

$40,000 buys a pretty nice diy off grid system. My utility cost was going to about $25,000.

You may find managing your big loads like welders and pumps requires little effort and reduces your system requirements a lot. It’s just part of being off grid.

Might want to check out the “systems” at currentconnected.com. No affiliation.

 

[Mattb4]

Thanks for all the replies and advice. It reassures me that I've found the right forum to join.

Corrections:

Yes, I live in BC Canada but the land is in Nova Scotia. One site I visited said I will get 1090 equivalent hours of sunshine per year.

The problem with the grid isn't the cost so much as the legal problem of not haveing the easements required from other landowners to tun the distribution line to the end of the road where I am. I'm not completely blocked, I could pay off one landowner and get power to my lot for about $40k. Then I get to pay a power bill every month. I think if I look at total cost over a 15 year span a solar system may be the better way to go.

The lot is 4 acres on the ocean at St Mary's Bay with the most incredible sunsets. This land is well worth the effort to develop.

I figured I would need an audit of some sort so I ordered a 16 channel power monitor from Amazon, it has current clamps that go on the branch wires at the fusebox and measure/monitor/log what every outlet in the house is usung and when. This may take couple of weeks but I hope to be able to differntiate between household, home business and weekend hobby power requirements.

At the new location I'll have a small house and up the slope a couple hundred feet will be a very large utility building that will have my woodworking, electronics shop and automotive shop. My wife finally gets a house that is just a house and I get the mother of all man caves. This could help or hinder the design, The utility building may need minimal power when I'm not there, it's unheated and has no plumbing. I thought I'd put the diesel genny up there and run it when I wanted to work with the big machines. This would mean the solar only needs to be scaled for the house.

I'll start with the audit.

Thanks!

Wow! That is quite the change going from BC to ocean side Nova Scotia. You will also want to know what access you have to ordinary supplies. Quite the adventure especially as a retirement situation.

 

[JayArr]

Thanks Matt, yes we're trading a view from our living room window of Mount Baker in Washington state for four acres and a view of St Mary's bay. Totally different.

Interesting Video Danke, I think I understand that the charge controllers are AC linked to the inverter generators but he doesn't really say. I always imagined DC linking my PV directly to my batteries. I don't know why, I'll have to do some research to decide.

Also: $27KUSD for batteries - yikes! I hope that if I go with FLA that can be charged in the cold I will save some $$?

 

[Texican]

Thanks Matt, yes we're trading a view from our living room window of Mount Baker in Washington state for four acres and a view of St Mary's bay. Totally different.

Interesting Video Danke, I think I understand that the charge controllers are AC linked to the inverter generators but he doesn't really say. I always imagined DC linking my PV directly to my batteries. I don't know why, I'll have to do some research to decide.

Also: $27KUSD for batteries - yikes! I hope that if I go with FLA that can be charged in the cold I will save some $$?

I think you would regret getting FLA batts. good chance of wrecking them, wont last as long, maint pain
pay once and be happy.
maybe build a small outhouse sized closet for the batts with killer insulation
I am happy so far with my eg4 lifepower batts

 

[DIYrich]

When considering FLA batteries, take into account usable range. FLA shouldn't go down under 50%. LiFePO4 can go down to 10%

 

[JayArr]

I'll look but keep in mind I'm 59 years old so I don't want to pay extra for anything to last longer than 10-15 years. A great deal on batteries that will last 20-25 years is lost on me. I'll be designing with a 15 year lifespan.

The 50% rule is good to consider because it changes the math.

 

[JayArr]

Here is what I purchased from Amazon to monitor my current house.

https://www.amazon.ca/3-Phase-Emporia-Electricity-Metering-Conserve/dp/B08CJ3VC79/ref=sr_1_3?crid=XGL8LLMFQ3BM&keywords=emporia&qid=1679876247&sprefix=emporia%2Caps%2C187&sr=8-3

 

[Hedges]

Also: $27KUSD for batteries - yikes! I hope that if I go with FLA that can be charged in the cold I will save some $$?

FLA costs $0.25/kWh of cycle life. Some can last 20 years.
AGM costs $0.50/kWh of cycle life. Some can last 10 years.
LiFePO4 can cost $0.05 to $0.50/kWh, depending on pre-assembled, DIY, brand, and claimed cycle life. Calendar life, some claim 30 year design life.

You can power anything and everything you want PV direct while the sun shines. PV panels can be had for $0.12 to $0.50/W (STC rating) but mounting hardware can add a lot. If quality will outlast the inverters and batteries. I put grid-tie PV hardware around $0.025/kWh (amortized over 20 years, if 100% of kWh are used.) Battery inverters are more expensive, at least if they have good surge capability.

Schneider/Trace, Outback, SMA are among the low-frequency versions to consider. Some others maybe also. Some of those brands also have high frequency, and Midnight just introduced one.

For an off-grid system, both split-phase and 3-phase are options.

 

[JayArr]

No grid tie for us so that's a savings. The house will go in the middle of this clearing with the water to the NW. The roof is a shed style with the high point at the water side, about 15 feet tall then sloping down to 8 feet at the SE side. (slope is 1/12, about 5 degrees) I hope to just mount the panels flat on top of the roof, they'll be aiming pretty much south east with no obstructions all day long.

Can I just make up for any deficiency from the solar array on any given day with the diesel genny? Instead of buying twice as much PV and twice as much battery I'd like to be closer to what I need and fall back on the genny. I don't want giant pole mounted arrays on the land, some panels on the roof is OK.

On any given day in retirement I may want to work in the wood shop or on a car, I expect to head to the utility building and turn on the genny for power for compressors and saws and such, I envisioned that while the genny was on it would also top up the batteries down at the house as well. On days when I don't work in the shops I would need to check battery state in the evening and run the genny to top up if I thought I wasn't going to make it to morning.

I'd love to use Schneider/Trace, I've got lots of familiarity with their engineering. I've been repairing Xantrex/Trace RV inverters for 10 years, everything from the old Freedom 458 MSW to the Prosine 3.0 units in large buses and RVs. It would be very fitting to have a wall covered in Schneider boxes in retirement.

If I could get a FLA bank to last 15 years that would be about perfect, by my late 70s I may be ready to sell the place and go live in a home and terrorize the nurses.

 

[EastTexCowboy]

Here is what I purchased from Amazon to monitor my current house.

https://www.amazon.ca/3-Phase-Emporia-Electricity-Metering-Conserve/dp/B08CJ3VC79/ref=sr_1_3?crid=XGL8LLMFQ3BM&keywords=emporia&qid=1679876247&sprefix=emporia%2Caps%2C187&sr=8-3

Those look pretty slick. I've been thinking about buying one just for the fun of it. My HVAC guy has one just like that and loves it. In your case, you are definitely on the right track to get some hard data on not only how much you're using but where you're using it. A much smarter method than just guessing and buying a bunch of stuff. Good luck! You'll find plenty of help from the folks here if you find yourself needing it.

 

[Hedges]

No grid tie for us so that's a savings. The house will go in the middle of this clearing with the water to the NW. The roof is a shed style with the high point at the water side, about 15 feet tall then sloping down to 8 feet at the SE side. (slope is 1/12, about 5 degrees) I hope to just mount the panels flat on top of the roof, they'll be aiming pretty much south east with no obstructions all day long.

Ideally have your panels SE, half SW. Which would mean something different about roof slopes, or ground mounts or an awning.

The idea would be more flat power throughout the day. Loads can be powered without cycling the battery and you enter the night with higher SoC. Smaller battery can work, or shallower cycling so a forklift battery lasts longer.

Can I just make up for any deficiency from the solar array on any given day with the diesel genny? Instead of buying twice as much PV and twice as much battery I'd like to be closer to what I need and fall back on the genny. I don't want giant pole mounted arrays on the land, some panels on the roof is OK.

You can, but generator costs $1.00/kWh. PV and inverter or SCC costs $0.025. If you go with LiFePO4 not LA, can cost as little as $0.05

With those cost differences, you can oversize PV 10x expected consumption and only be spending $0.25/kWh. That will help on cloudy days. It will also let you get by with less battery.

I use a LOT of power so I'm curious as to whether I can make this work. I'm currently using 70-80 kWh per day because both my wife and I work from home and I run an electronics repair shop from here. On the weekend I either work on cars, do some welding or build something in the wood shop.

For those of us with 6 hours effective sun, 13kW of PV panels. For you maybe 26kW. So 10x oversize starts to get absurd, but install all you can, blanket the roof. Look for quality name panels used from solar farms. We have Santan solar, you may have other options.

26kW at 0.2 kW/m^2 is 130m^2

Winter of course it presents less angle to the sun. Your roof slope will primarily be driven by architecture, but maybe you can make it steeper. I think also SE will be significantly worse than S in winter. Check an insolation calculator.

 

[Nobodybusiness]

We've purchased our retirement land and are going to build a house in the country then sell the house in the city.

We've got problems with getting the grid to our lot since easements are required from every property along the route and some of the owners are incommunicado and others want large cash payments in order to sign. I'm trying to compare apples to apples by extrapolating each scenario out by 15 years and measure the total cost of power.

I'll have a huge south facing sloped roof for panels so I thought I'd look into off-grid. I'm familiar with inverters and charge controllers from my RV but have no experience in the whole house hardware.

I use a LOT of power so I'm curious as to whether I can make this work. I'm currently using 70-80 kWh per day because both my wife and I work from home and I run an electronics repair shop from here. On the weekend I either work on cars, do some welding or build something in the wood shop.

I'm thinking I need a big genny to run on the weekends when I'm using high power machines like welders, compressors and saws. I'll need a small solar system to keep the lights on and the internet running in the utility building and then there is the house. It'll be small, about 1500sqft and the stove, water heater and dryer will all run on LPG. Heating will be by LPG in floor radiant heat with a wood stove in the living room. I hope the same genny can serve as backup and or battery charge when sunlight is not enough.

For a first step I've ordered a power analyzer to go on my breaker panel and monitor and record what each branch uses, when it uses it and for how long. I've really got to get a grip on where I'm using so much power. I'm thinking I need to somehow cut it in half at the new place. 35kWh per day? We'll be retired so that should help.

I'll be in and out of there asking questions about how to do things and such, I hope I've picked a friendly forum to join.

JayArr

You have to have an easement for a driveway.

Can the power not be run that way or are you just not wanting to do it that way?

Or is it more complicated than that?

Just curious.