diy solar

diy solar

14.4 KW solar, 40.96 kWh backup, 2 solark 15k inverters, off grid family home, doable or delusional?

ksmithaz1 said:
IMNSHO if you are going solar, I'd go all the way electric and only run propane/other as a last resort. $500-$1000 for a gas appliance. $1500 for another 25A inverter to meet demand. The battery is the big deal, but even though the thing really uses juice, I'd roll it and plan for some extra battery. Panels are cheap. The idea is to not pay the Gas company or the Power company.
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I have a grid tied system with full net metering. So for me, yes I do have an electric drier and I have no plans to replace it. Driers along with water heaters are energy pigs. Now your situation in Phoenix is better than mine. You are farther south and there are very few long periods of cloudy days. In Louisiana the situation is probably somewhere between us. Because this is a fully OFF GRID system, just pulling a few KWHs from the grid to dry a load of laundry is not an option. Putting off laundry for a week because it is cloudy may not be an option either. For someone trying to live a normal life in an off grid home, running out of power because you needed to do laundry really isn't an option either.

My situation is different. With full net metering I can push power to the GRID during the day and pull it back later for free. My batteries are there just to get me through power failures without extreme inconvenience. If we get a longer outage during the winter when my PV generation is consistently less than consumption, I will need to run a portable generator once or twice a day to top the batteries off. Yes pulling out and hooking up a portable generator is a pain, but this works for me. It is a situation I can live with if I have to in the event of a power failure at the worst possible time. I don't think this is acceptable for someone fully off grid.

For someone fully off grid and just looking for a feasible system, I think what makes the most sense is to design the system such that it can supply your house 95% of the days. Then supplement that with a generator about 15 days a year. Getting to that 95% is going to be significantly cheaper if the overall load on the system is less, so reducing overall consumption is part of the solution. This is especially true with batteries. I would make sure the system has plenty of KWs of inverter capacity, especially surge current if driving a well. For battery storage, I would make sure I had 1 day of storage for a winter day, and maybe a little more to make sure I can run A/C after we lose PV production in the evening. In summer you get better PV production and if it is cloudy A/C consumption also drops, so I wouldn't size this for one day of the highest energy use. Let's say we go with 30 KWHs of storage and that gets us through 95% of days without needing the generator. If you have sized the system to meet the power requirements 95% of the days, you will run the generator 15 days a year.

Now lets say that instead we double our storage to 60 KWH. That might cover us for 98% of the days. We would still need to run the generator about 6 days a year. So doubling storage will cost us about $9000 and save us from 9 days of generator use.

The cost of generating 1 KWH on a natural gas generator is about $0.20. The cost of storing 1 KWH in a battery is about $300.00. Yes the battery can be used more than once, but you won't break even until you have completed 1500 cycles. It will take you more than 150 years to recover the cost. My idea is to not pay more overall for a comfortable off grid life style.

Now if the system is undersized, the only down side is that the generator will run more than you planned. Based on experience, you could add either more solar or more storage depending on where the system is falling short. Adding more panels and possibly a charge controller or more batteries shouldn't be a big deal.
 
If you are off-grid, you are talking propane, not NG, but I digress. I'm on grid the next 3 days because there is no sun, and I can't go that long on 64KWH. None-the-less I still dry clothes off the batteries, because most of the time, its energy I don;t have a place to store anyway. If I was fully offgrid, I would look for 200+KWH of batteries, and a 10KW genny. The genny kicks on to charge batteries if they get below 20%, not to run the house, per-se. I would always have inverter capacity to meet demand for the house. Averaging out the Dryer and HWH in the overall scheme it's not really that significant for me, summertime AC pretty much runs 24x7, but obviously would be in a more moderate climate.

Off-grid for ~ 2000sqft I'd have ~150A of inverter to go with the 200KWH of batteries. I'd have a propane generator, and if the climate for the area demanded it, an alternate heat production system (pellet,wood,etc). You'd want about 40KW of panels, I'd go to 60 depending on the sunshine situation, and the space constraints getting them up. The objective in my case would not be 'saving money', though the checkbook does have a bottom. The objective would be independece and self-sufficiency without sacrificing my quality of life.

Frankly if I didn't charge cars or run the air my average day is maybe 40-45KWH. Even on a crappy day you generally get some solar, but it does depend on where you are. I'd really want to be all-electric. If you get enough panels at some point your batteries are full and you are producting more power than you can use and store. I think that is where you want to be, so 95% of the time you can just ignore it, but periodically you may have to run the generator if the sun refuses to shine for an extended period. Just avoid laundry when the generator is running, which should be a relatively small window here and there.
 
As a side note, extra panels can make up for some battery if it can either supplement enough when production is awful, and recharge enough when production is good. Extra battery can make up for fewer panels if you have enough battery to carry you through when production is low. At some point battery becomes the limiting factor.
 
ksmithaz1 said:
Averaging out the Dryer and HWH in the overall scheme it's not really that significant for me, summertime AC pretty much runs 24x7, but obviously would be in a more moderate climate.
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For most solar systems, summer is not the time you come up short. Yes, the A/C runs a lot, but PV production is very high. I am consistently exporting power in the summer. It is winter when my system produces less than I consume. So during winter a hot water heater and electric drier really would be a significant portion of electricity use. Every time I do a load of laundry my KWHs per day spikes. Now you may be suggesting that @Themillpondhouse buy $60,000 of batteries rather than minimizing his electricity use by buying a $1000.00 drier. I think most people are looking to be a little more practical.

Yes, I know off grid people use propane. I just don't have a good estimate on the cost of generating a KHW of electricity from propane. I am quite certain it is less than $300.00.

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ksmithaz1 said:
If you are off-grid, you are talking propane, not NG, but I digress. I'm on grid the next 3 days because there is no sun, and I can't go that long on 64KWH. None-the-less I still dry clothes off the batteries, because most of the time, its energy I don;t have a place to store anyway. If I was fully offgrid, I would look for 200+KWH of batteries, and a 10KW genny. The genny kicks on to charge batteries if they get below 20%, not to run the house, per-se. I would always have inverter capacity to meet demand for the house. Averaging out the Dryer and HWH in the overall scheme it's not really that significant for me, summertime AC pretty much runs 24x7, but obviously would be in a more moderate climate.

Off-grid for ~ 2000sqft I'd have ~150A of inverter to go with the 200KWH of batteries.
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Insane

ksmithaz1 said:
I'd have a propane generator, and if the climate for the area demanded it, an alternate heat production system (pellet,wood,etc). You'd want about 40KW of panels, I'd go to 60 depending on the sunshine situation, and the space constraints getting them up.
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Insane

ksmithaz1 said:
The objective in my case would not be 'saving money', though the checkbook does have a bottom. The objective would be independece and self-sufficiency without sacrificing my quality of life.
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Conservation always pays. The money spent on Insane systems mentioned above would be better spent on conservation.

The quality of life can actually improve with conservation and allow for independence and self sufficiency without spending enormous amounts of money.


ksmithaz1 said:
Frankly if I didn't charge cars or run the air my average day is maybe 40-45KWH. Even on a crappy day you generally get some solar, but it does depend on where you are. I'd really want to be all-electric. If you get enough panels at some point your batteries are full and you are producting more power than you can use and store. I think that is where you want to be, so 95% of the time you can just ignore it, but periodically you may have to run the generator if the sun refuses to shine for an extended period. Just avoid laundry when the generator is running, which should be a relatively small window here and there.
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Considering your location and you don't have a large heating load during short winter days with limited PV, you really need to look more at conservation such as hanging clothes outside to dry or purchasing a heat pump dryer.
 
Doggydogworld said:
You're wise to consider expansion. You can start with a minimum system and just run the generator more often the first year. Then use that data to decide if you need to expand the array, the batteries or both.
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I think this is good advice.

Unless you have buckets of money, it is going to be far cheaper to supplement the solar with occasional generator use than to size the system for a worst case scenario. A properly sized system should make all the power you need on sunny summer days. It is perfectly acceptable to size things such that your generator runs once or twice a day on dark winter days to supplement the solar. Now if you install a heat pump for heating, rather than a propane furnace you will be drawing a lot more power during the time of year with the smallest solar production. You would need to take that into account. I image your winter solar production is going to be better than mine, so maybe this is feasible for you.

Part of my issue is that my HOA and roof design means my panels are East and West facing so Nov, Dec, and Jan solar production is really poor. I have a lot of west facing panels that generate far into the evening in the summer. My production actually peaks at 3 PM. I get far more production than needed for the A/C so I am exporting all afternoon. Another hint I have is that if you can design the system with say 8-9 East facing panels, 8-9 West facing panels, and the rest facing South, that will minimize the number of hours a day where you depend on your batteries. If you are going with a ground mount, you could also look into vertical bi-facial panels that run north south rather than the East West Panels. A broader, flatter power production curve means you can consume more power as it is produced. Each time you go into and out of your batteries, you lose efficiency. Each hour you can extend your production is one less hour that you need to store energy for over night. For a grid ties system with full net metering, having all panels facing south makes the most sense. For an off gird system getting a flatter power production curve is helpful.

You are really going to need a generator anyway. Trying to minimize generator run time, is really an exorcise in diminishing returns. Getting to 90% energy independence without the generator might cost X. Getting to 95% might cost 2x. Getting to 98% might cost 4X. At some point, it is time to quit throwing more hardware at the problem and just run the dang generator.

On generators there is something you should be aware of. There are really four main choices:
  1. A portable generator that you roll out of the garage and plug in to the house and manually turn on. I don't think this is adequate. First these portable generators aren't designed to run in bad weather. When will you need your generator most? Also you need to change the oil once a day if you are using it continuously.
  2. An air cooled standby V-twin 3600 RPM generator. This generator is going be like a Harley Davidson running at full throttle.
  3. An liquid cooled standby 4 cylinder 1800 RPM generator. This generator is going be small auto engine running at highway speed.
  4. A diesel standby generator. These can run for thousands of hours and are very reliable.
#2 is designed to run for a few hours a year in an emergency for a grid tied home. They are designed to last for about 40 days of continuous use if you change the oil once a week. #3 is going to be OK if you need to run it for a week or two while your inverter is repaired. If you run it 300 hours a year (30 MWHs) it should last 10 years. #4 you could run it non-stop for a year as long as you shut it down occasionally to change the oil These have a service life of 10,000 hours or more.

I think #3 might be the sweet spot especially since you already plan to have propane. These are going to be more expensive for the same KW rating than the air-cooled, but they should be more reliable, have a longer service life, and and be quieter too.
 
Themillpondhouse said:
My husband has a few years of electrical experience as a journeyman, but not with solar. He is familiar with industrial installations as well and very mechanical savvy. He feels pretty confident in the install. He also thinks I am crazy and overthinking this. I think for new build construction permitting in our area, a licensed electrician may have to make the final connections or inspect the system (our builder is willing to help us figure this out).
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It ain't rocket science. A few YouTube videos and a case of beer and I gotter done. (Having a general understanding of electrical systems does help, but your hubby has far more of that than I do).

My biggest concern was making sure that the system "looked" professional. I didn't want to have wires running all over the place and stapled to the wall. I ran everything in 6" gutter boxes and 2" metal conduit. I bought all the proper tools like a hydraulic crimper and a hole punch system. I made sure all the wiring is properly sized. With the Schneider inverters and the PDP panel (that's the one without the green screen) , the Schneider PDP panel contains all the required breakers and connection points to hook together the multiple inverters. The PDP panel is pre-wired with one wiring harness for the first inverter. You just need to hook the wires (which are labeled with ferrules pre-installed) into the 1st inverter. The second inverter and wiring kit has a pre-made wiring harness that connects the second inverter into the PDP panel. For a DC coupled system, you would also need Charge Controllers. If one Sol Ark was enough, that would be great. With two of them, hooking everything together is going to be an issue. A bunch of connections will need to be made. For example the incoming generator wires have to Y into each inverter.

The Schneider system can easily expand to include additional inverters and charge controllers without all kinds of external wiring. It is actually a very slick system.
 
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I didn't fully read everyones reply... But let me add, with the well situation, you could go with a large storage tank, and "automate" the pump to fill your storage tank during the day, when your demand is lower and the sun is shining .. I think if you have the cleared ground space, and have a good southern exposure, you can make it work. The overnight / cloudy days will be the costly part because of batteries.... Can't wait to hear more about your decision / progress
 
wheisenburg said:
For most solar systems, summer is not the time you come up short. Yes, the A/C runs a lot, but PV production is very high. I am consistently exporting power in the summer. It is winter when my system produces less than I consume. So during winter a hot water heater and electric drier really would be a significant portion of electricity use. Every time I do a load of laundry my KWHs per day spikes. Now you may be suggesting that @Themillpondhouse buy $60,000 of batteries rather than minimizing his electricity use by buying a $1000.00 drier. I think most people are looking to be a little more practical.

Yes, I know off grid people use propane. I just don't have a good estimate on the cost of generating a KHW of electricity from propane. I am quite certain it is less than $300.00.

​

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I keep forgetting about the free propane that comes with the gas dryer. This is not about being efficient. Insulate, High seer HVAC systems, etc if your building. Dumb not to. Off-Grid, the solar infrastructure is CAPEX not OPEX. To me I'd want to pay up front and make my OPEX as low as possible. I want to be self-sufficient. The more batteries you buy the less you need to rely on a generator. You have to buy enough to get you past your average daily load +10% times the number of days of ZERO solar production you are willing to tolerate before relying on the genny. Get a gas stove and dryer, and you lower that load, but it won't get you out from under the gas bill. Pick your poison, at some point you rob Peter to pay Paul.

If your winter solar production is that abysmal and you can't overpanel to make up for it, then you need to decide if a few months of propane to run a generator making up for missing solar output to run an electric dryer/stove is more/less than running your dryer/stove on propane 12 months a year. Definitely a valid discussion.

You could have two stoves and two dryers, one of each. Swap them out with DST. You could probably get by with 120KWH ~ $25K of batteries, at the expense of fewer days of no solar thus a bit more propane to run the genny. Depending on what the boss is willing to tolerate, you don't have to do "optional" laundry during a full week of no sun. Again it does depend on where you live. If the folks here are to be believed, the abysmal period is ~11/1 until ~3/1, maybe 3-4 months. Even at that they report good days, weak days, and bad days for solar. I just don't think electric appliances are really going to beat you up that badly in the winter vs burning propane year round.
 
1201 said:
If you're going to be in a well, look for a solution that has a low surge. Like the grundfos pumps.

I wouldn't get Mr cool units. Get a regular mini split and a $120 vacuum pump and gauge kit. That way you can shorten the lines as needed
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I sell Grundfos. They also make solar powered well pumps: https://product-selection.grundfos.com/us/products/sqflex?tab=explore

But I sell to heavy industrial/chemical users so no I cannot sell directly to you. Easy enough to find online though.
 
wheisenburg said:
I have a grid tied system with full net metering. So for me, yes I do have an electric drier and I have no plans to replace it. Driers along with water heaters are energy pigs. Now your situation in Phoenix is better than mine. You are farther south and there are very few long periods of cloudy days. In Louisiana the situation is probably somewhere between us. Because this is a fully OFF GRID system, just pulling a few KWHs from the grid to dry a load of laundry is not an option. Putting off laundry for a week because it is cloudy may not be an option either. For someone trying to live a normal life in an off grid home, running out of power because you needed to do laundry really isn't an option either.

My situation is different. With full net metering I can push power to the GRID during the day and pull it back later for free. My batteries are there just to get me through power failures without extreme inconvenience. If we get a longer outage during the winter when my PV generation is consistently less than consumption, I will need to run a portable generator once or twice a day to top the batteries off. Yes pulling out and hooking up a portable generator is a pain, but this works for me. It is a situation I can live with if I have to in the event of a power failure at the worst possible time. I don't think this is acceptable for someone fully off grid.

For someone fully off grid and just looking for a feasible system, I think what makes the most sense is to design the system such that it can supply your house 95% of the days. Then supplement that with a generator about 15 days a year. Getting to that 95% is going to be significantly cheaper if the overall load on the system is less, so reducing overall consumption is part of the solution. This is especially true with batteries. I would make sure the system has plenty of KWs of inverter capacity, especially surge current if driving a well. For battery storage, I would make sure I had 1 day of storage for a winter day, and maybe a little more to make sure I can run A/C after we lose PV production in the evening. In summer you get better PV production and if it is cloudy A/C consumption also drops, so I wouldn't size this for one day of the highest energy use. Let's say we go with 30 KWHs of storage and that gets us through 95% of days without needing the generator. If you have sized the system to meet the power requirements 95% of the days, you will run the generator 15 days a year.

Now lets say that instead we double our storage to 60 KWH. That might cover us for 98% of the days. We would still need to run the generator about 6 days a year. So doubling storage will cost us about $9000 and save us from 9 days of generator use.

The cost of generating 1 KWH on a natural gas generator is about $0.20. The cost of storing 1 KWH in a battery is about $300.00. Yes the battery can be used more than once, but you won't break even until you have completed 1500 cycles. It will take you more than 150 years to recover the cost. My idea is to not pay more overall for a comfortable off grid life style.

Now if the system is undersized, the only down side is that the generator will run more than you planned. Based on experience, you could add either more solar or more storage depending on where the system is falling short. Adding more panels and possibly a charge controller or more batteries shouldn't be a big deal.
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You can get an all-in-one washer/dryer heat pump unit. That would take less energy than a regular electric dryer. Also, you can still do some essential laundry on cloudy days if your wardrobe is minimal. Just hang the clothes up to dry.

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Not as effective, but you can hang clothes up inside too.
 
Danke said:
You can get an all-in-one washer/dryer heat pump unit. That would take less energy than a regular electric dryer.
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These heat pump dryers are more efficient. They also cost twice as much and they are far more complex and hence more unreliable. The same can be said for heat pump hot water heaters. Also, for a family, it does mean that it will take at least twice as long to do each load of laundry since you can't have both the washer and dryer going at the same time.

You may save energy, but is it enough to make up for everything else?
 
ksmithaz1 said:
I keep forgetting about the free propane that comes with the gas dryer.
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It's not free. If you double your batteries from 30 KWHs to 60 KWHs and use an electric Dryer you might reduce your generator days from 15 to 6. Instead you go with 30 KWHs and a gas dryer, so you save $9000 in batteries. Instead you will generate say 30 KWHs of additional electricity from the generator for 9 days each year. So 270 KWHs at .20 at KWH = $54.00 a year for the extra propane. The estimated annual cost to run a propane dryer is about $100. The combined cost of additional propane with my suggested configuration is $158.00. That means it will take you about 58 years to break even on the cost of your additional batteries. Most (not insane) people will look for a payback period of under 10 years to consider a project financially viable.

Do you think you could find any investors if you pitched them a project with a 58 year payback?

Now you are free to do what ever you want with your money, but if you are advising other people that they need 120 KWHs of batteries as a "Starter off grid system", you have some duty to know what the hell you are talking about.
 
I don't want to get into a battle with anyone, but I have to say that I think @wheisenburg is giving some great advice here. Keep the system size reasonable, and just plan for a reasonable amount of generator use from time to time. You're not gonna destroy the planet with occasional, overall-infrequent use.
 
You need to plan for the replacement cost of your critical hardware anyway and you'll learn a lot by living with a system for a while. So if your budget is $60K because that's what it would cost to get grid power, I'd argue for spending less than half that up-front on your electricity/energy system. The rest you save (somehow) for future expansion and hardware replacement.

We don't know enough about your financials to say what the best way to put that money aside is, but some examples might be;
  • If you're going to have future income and you have existing high interest debt, pay some of it off.
  • If you're already betting on the stock market doing reasonably, maybe put it into the S&P500.

A few other points;
  • Short term, you can maybe swing a huge house and off-grid system such that you rarely have to think about energy use, but I think being a bit more frugal and energy conscious up-front will make the long-term much more viable (and pleasant) - leaving you more flexibility to grow and adapt as you learn. This does mean your whole family needs to be really on-board though. To paraphrase what someone earlier said, building something completely new from scratch is not for the feint of heart.
  • There is a whole industry around energy efficient homes, at the very least get advice from someone professionally. You'll probably end up with thicker walls, more attic insulation, etc. than you imagined.
  • Consider at least designing in an area near the house where a ground-source heating/cooling loop could be buried or maybe get this done as part of your site-leveling/foundation-work if the spacing around your building site is going to be tight. Infrastructure like that - and things like up-sized conduit very rarely go bad and can save a ton of money in the long run if you do the work at auspicious times in the overall project.
  • Try and make the house part of your electrical system as conventional as possible with the only unusual bit being how power gets to the main breaker panel.
  • Consider building at least a minimal backup catchment water system. Wells are risky business. They're expensive, go dry, get contaminated, have failed pumps, etc. Every inch of rainfall on a 2500sqft house is around 1500 gallons and you already have to do most of the work to catch it in order to protect the house. You might as well have a few tanks and a strategy to get/keep it clean.
 
I think the USA in particular is way over fascinated with things being as large as possible. I've seen several people here that think even a 200 amp service is not enough and honestly that is crazy to me. I am able to run an all electric house in Florida with certain things in place like HPWH and easy start on the HVAC with a single 12 KW output inverter, that's 50 amps.
Conservation is not as sexy as electrically equipment but it has a faster return all day long.
 
Quattrohead said:
I think the USA in particular is way over fascinated with things being as large as possible. I've seen several people here that think even a 200 amp service is not enough and honestly that is crazy to me. I am able to run an all electric house in Florida with certain things in place like HPWH and easy start on the HVAC with a single 12 KW output inverter, that's 50 amps.
Conservation is not as sexy as electrically equipment but it has a faster return all day long.
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Same here- the US is 'power mad' when it comes to many things- 'utes' with 4 times the horsepower of my 8 tonne tilt-tray truck (and fuel consumption to match), HUGE electrical demand (some US fridges use more than my entire 3 bedroom house with three people living in it- including a 'gadget mad' older guy (guess who that was lol) and a teenager who never learned what an off switch was...)
Our daily consumption was around 7-10kwh a day- in total... running off an 80A 240v mains supply and 6kw of gridtie solar, the electricity bill was usually- zero...
(in fact we often got a few bucks back from them...)
Seriously lol
(they direct deposited the 'bill' amount on the due day straight into our bank account if it was a 'negative bill')
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Many offgrid houses here in Australia comfortably run multiple A/Cs, cook on electric and have a lifestyle that it is hard to tell you are actually running purely from solar...
Of course solar here seems to be a lot cheaper than the US as well which helps- people quoting multiple tens of thousands for systems is crazy high price wise (gridties here cost about $3500Au or about $2300US- thats fully installed, no more to pay,and will give you about 35kwh a day in generation, where a 10kw system (requires 3 phase on at the house) is about $6500Au ($4200US) again fully installed, no more to pay, and will generate about 52kwh a day...

My own offgrid system cost me under $2000Au for ex gridtie panels (secondhand, from an installer doing upgrades/repairs) 72x 250W panels totaling 18kw of panels, the most expensive thing was the battery bank ($11800Au) for 20kwh of LYP batteries (better than LFP for either high or low temp applications) 16x400Ah cells- the total system cost $17500Au in total for everything... ($11400US)- sufficent to run a workshop with a mill and metal lathe, welders, air compressors etc, and a 3 bedroom house with A/C- in total that 18kw of solar will be getting up to 90kwh a day...
And I plan to buy an EV this year to boot lol (looking at the BYD Atto3)
all offgrid...
 
Madcodger said:
I don't want to get into a battle with anyone, but I have to say that I think @wheisenburg is giving some great advice here. Keep the system size reasonable, and just plan for a reasonable amount of generator use from time to time. You're not gonna destroy the planet with occasional, overall-infrequent use.
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This isn't a battle. It's a discussion about the merit's of going "off-grid" with gas, ie propane based appliances vs using propane purely as a backup to run a genny when the sun isn't shining and the batteries are depleted, with all-electric appliances.
wheisenburg said:
Now you are free to do what ever you want with your money, but if you are advising other people that they need 120 KWHs of batteries as a "Starter off grid system", you have some duty to know what the hell you are talking about.
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This comment was perhaps a bit coarse, but needs to be taken in context. Pretend you are in a bar discussing some decision made by a player or coach. Then order another round. I am not offended by someone articulating points they feel are important with emphasis that does not always come off the same way in print, as it would if talking across a table. Always take a step back and don't take indirect offense. Good writing is very hard, I'm barely adequate myself, it's easy for it to come off a bit abrupt.

I think my takeaway is the OP is talking about being "off-grid" vs being "off-grid". To me off-grid means self-sufficient. I also think we lose site of overall expendature vs single project expendature. I'm going "off-grid", I have dirt somewhere, and I'm building a driveway of some description to a 2000 square foot house., maybe a garage/workshop, and likely a small structure to house a power plant. So I'm spending maybe $200-300K to put up the structure(s) themselves, possibly more depending on prep. I can put up a bare minimum power plant for $40K or I can put up something dramatically better for $70K... I think there is more to ROI than direct correlation, in particular in the context of a larger project. Further you can't really do a "starter" off-grid system, at a miniumum it must be able to meet the demand of the facility you are building. I'm thinking nice house running water, 3-4BR 2-1/2 bath, garage, not cabin in the woods.

The arguments have merit, but I think they make some assumptions. First, I'd like a bit more detail on the dollar figures for running the appliance, and the genny. They both seem very low to me, and we need to throw in the HWH as well if we are going all electric. The second thing is an assumption that the cost of propane is static, which I think is unlikely, so what we are talking about for ROI is the width of the gaps and the stability of the cost of propane. I'd also like more definition on the 15 vs 6 days of genny. Sounds reasonable but I get so much sunshine here it's hard to get a grasp on expectations from other climate zones. I have 60KWH of batteries and flipped last night about 0300 hours. Came back online at 0900. Adding another 30KWH would have eliminated that flip, this will happen, but there is surely no ROI for it, probably will cost me $4-6.

Also based on taking the argument to the other extreme, you might be better off skipping the solar all-together, just get two genny's alternate them, and run them off propane, get all propane appliances, and get your electric needs down to the bare minimum, maybe a small inverter, and minimal batteries to allow the genny's to cycle. Let the genny system work like a well pump and a pressure tank except for power instead of water.

@B-Mod, in the frozen tundra, has some 200+KWH of batteries, and 50KW of panels. @timselectric (I think he's in Appalachia) is trying to catch up once he get's off his butt and puts up all those panels he bought, and builds out another string or two of batteries. I'm guessing neither would choose to pay for propane if they could build out to eliminate the need. This makes them the local hero's of the forum. To resolve the "Genny days" I think we need to have a good handle on a couple of things. Recovery time to fill battery capacity you have, How long the battery capacity you have will last without any supplement. When this happens how long does it last. What is the overall energy cost when that occurs? I'm not sure we are looking for ROI as much as being energy independent.
 
ksmithaz1 said:
This isn't a battle. It's a discussion about the merit's of going "off-grid" with gas, ie propane based appliances vs using propane purely as a backup to run a genny when the sun isn't shining and the batteries are depleted, with all-electric appliances.

This comment was perhaps a bit coarse, but needs to be taken in context. Pretend you are in a bar discussing some decision made by a player or coach. Then order another round. I am not offended by someone articulating points they feel are important with emphasis that does not always come off the same way in print, as it would if talking across a table. Always take a step back and don't take indirect offense. Good writing is very hard, I'm barely adequate myself, it's easy for it to come off a bit abrupt.

I think my takeaway is the OP is talking about being "off-grid" vs being "off-grid". To me off-grid means self-sufficient. I also think we lose site of overall expendature vs single project expendature. I'm going "off-grid", I have dirt somewhere, and I'm building a driveway of some description to a 2000 square foot house., maybe a garage/workshop, and likely a small structure to house a power plant. So I'm spending maybe $200-300K to put up the structure(s) themselves, possibly more depending on prep. I can put up a bare minimum power plant for $40K or I can put up something dramatically better for $70K... I think there is more to ROI than direct correlation, in particular in the context of a larger project. Further you can't really do a "starter" off-grid system, at a miniumum it must be able to meet the demand of the facility you are building. I'm thinking nice house running water, 3-4BR 2-1/2 bath, garage, not cabin in the woods.

The arguments have merit, but I think they make some assumptions. First, I'd like a bit more detail on the dollar figures for running the appliance, and the genny. They both seem very low to me, and we need to throw in the HWH as well if we are going all electric. The second thing is an assumption that the cost of propane is static, which I think is unlikely, so what we are talking about for ROI is the width of the gaps and the stability of the cost of propane. I'd also like more definition on the 15 vs 6 days of genny. Sounds reasonable but I get so much sunshine here it's hard to get a grasp on expectations from other climate zones. I have 60KWH of batteries and flipped last night about 0300 hours. Came back online at 0900. Adding another 30KWH would have eliminated that flip, this will happen, but there is surely no ROI for it, probably will cost me $4-6.

Also based on taking the argument to the other extreme, you might be better off skipping the solar all-together, just get two genny's alternate them, and run them off propane, get all propane appliances, and get your electric needs down to the bare minimum, maybe a small inverter, and minimal batteries to allow the genny's to cycle. Let the genny system work like a well pump and a pressure tank except for power instead of water.

@B-Mod, in the frozen tundra, has some 200+KWH of batteries, and 50KW of panels. @timselectric (I think he's in Appalachia) is trying to catch up once he get's off his butt and puts up all those panels he bought, and builds out another string or two of batteries. I'm guessing neither would choose to pay for propane if they could build out to eliminate the need. This makes them the local hero's of the forum. To resolve the "Genny days" I think we need to have a good handle on a couple of things. Recovery time to fill battery capacity you have, How long the battery capacity you have will last without any supplement. When this happens how long does it last. What is the overall energy cost when that occurs? I'm not sure we are looking for ROI as much as being energy independent.
Click to expand...
This is what I meant about high prices in the US- $40K US is $61K Au- which would get you a system capable of running a small factory, or a string of houses... not a 'bare bones' bare minimum system...
$60KUS is $92KAU- which I would expect everything (including the panels) to literally be gold plated for that price...
My system (admittedly the panels were secondhand and only cost $2000, but everything was brand new) was a grand total of only $17500Au, and specced to run a workshop as well as the house, with no provision for anything except the solar...- to buy the panels new would have added an extra $10K to the price, making it a total of $27K Au or $17.5KUS
Some 'edge' cases (ie near the arctic circle lol) might cost more- but then I expect 'everything' costs more there...

A $92K Au system would be simply MASSIVE here, generating as much as some small powerstations!!!

(many remote Australian places used to use diesel gennys (propane- or LPG as it is called here is $$$$) but even diesel gennys can cost a small fortune to run- a 12kw diesel genny running 24/7 at minimum load costs around $22k a year just in fuel- at minimum load!!!...
Add the initial $12-14k to buy it and that 12kw solar system looks pretty good value lol)
(I'm only 3 hours drive from the capital city of Brisbane- and fuel here is usually between $2.20 and $2.40 a litre for diesel...head out west and that price can double...)
 
Have you tried to use the Sol-Ark system sizing tool or the solar panel calculator? I found them very useful. FYI we live in southeastern Louisiana and have the following system that powers our whole house.

Link to system tool: https://www.sol-ark.com/calculator/

Link to panel sizing tool: https://www.sol-ark.com/solar-panel-sizing/SolarPanelSizing.html

2 x Sol-Ark 15ks in parallel
3 x EG4 Power Pro's
6 x EG4 LL V2's
4.8k watts of AC coupled solar
4.8k of DC coupled solar
(PV will soon be doubled its the only weak point in my setup)
 

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Quattrohead said:
I think the USA in particular is way over fascinated with things being as large as possible. I've seen several people here that think even a 200 amp service is not enough and honestly that is crazy to me. I am able to run an all electric house in Florida with certain things in place like HPWH and easy start on the HVAC with a single 12 KW output inverter, that's 50 amps.
Conservation is not as sexy as electrically equipment but it has a faster return all day long.
Click to expand...

Funny you say that, to your point ... I've said it before I will say it again, it's all about DEMAND. I think part of this, and a big consideration if you're going off-grid, is how far we get pushed into electric vehicles. Compared to a HWH or Dryer an EV is an order of magnitude different. In particular if you want to run an EV and you are 'off-grid' it is likely you will be traveling a good distance when you do use it. At a generous 4.0mi.KWH driving back and forth to town 30 miles each way, it's going to eat 15KWH (a bit more likely). I split out a 100A panel for my entire all-electric home. This is a little tight if I'm charging my EV, however 125A will pretty much cover my needs, allowing a single car to charge without a potential demand issue. I will be upgrading as time permits. I'm running standard electric appliances, with an induction range, a third inverter is in my future.

Thus conservation is surely always important, but I would not build an off-grid power plant for a 2000 sqft home, without allowing for 150A of demand from the system no matter what the various components. This get's back to the ROI discussion on gas appliances. An EV is something I definitely have a great deal more control over when it get's charged. Since I would want to build out to be able to charge an EV the additional power to run an HWH/Clothes dryer must become a demand issue not an overall power issue. The two vehicles I have in an urban environment accout for about 1/5 of my overall power needs year round, higher in the winter, much higher in spring/fall, dramatically lower in the summer.

My "starter" solar system was built for 100A of demand, because I made that determination based on the fact that I moved everything into the 100A panel one thing at a time, and monitored it with sensors. The original intent was to shuffle loads with ATS's back and forth. What a PITA / dumb idea that was, though I did write the software to do it. IMNSHO if I'm going off grid, I don't mind maintenance, but I don't really want my power plant to have to stay at the top of my mind 24x7. I want the peace of mind and confidence to know it will perform without me being involved no matter the demand or power requirement.
 
Quattrohead said:
Why don't they make above ground well pumps with these motors? I feel like they're missing a huge market more so now than ever.
Click to expand...
Its a matter of what scales at the most cost effective and the uptake rate of the market if a product is considered
 
Some people can get themselves out of that Southwest-SoCal bubble way of thinking. Mostly Californians. They think the rest of the world either operates the way they do or should operate the way they do…ignoring all other factors.

So yes to a gas dryer. Maybe supplement with air drying, but all through my junior high to high school years I swore I would always have a dryer just to remove lint. Black T shirts? More like ugly gray t shirts after a few washings and no dryer.

All in one washer dryer? Yeah, most of those don’t air fluff. You have to literally peal the clothes off the sides of the drum after a dryer cycle.

Inverter dryer? Besides the low capacity and excessive long drying time, you are throwing out airborne microplastics. Better have an ERV return duct in the laundry room (to be fair, that’s not a bad idea anyway).

I would consider the inverter option as a supplemental dyer (if there is an ERV), but I dammed sure need a gas option too…as I don’t live in a desert.
 
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