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Off-Grid From Scratch

Sabre36

Solar Enthusiast
Joined
Dec 13, 2019
Messages
169
So the property in question is on about 300 acres in Northwest Maine. The house is wired for 240V but power was never brought into the structure due to the 2/3 mile long driveway and the cost CMP used to charge to run a private line.

Until last winter the house was fed via a gravity feed hand dug-well from the 1700's (it's old farm property). Over 1/4 mile of poly pipe was trenched through the thick woods to the well and it seems to have frozen, somwwhere, and we can no longer keep a gravity prime on it. It used to gravity-feed and now we need a jet pump in the basement to get any water.

Rather than re-visit more than 1/4 mile of trenching we are going to drill a well. I don't expect it to be too deep, tons of natural springs on the property, but we will need to be running this off batteries and an inverter or a generator or suck it up and bring in underground power.. We don't like the idea of a standard generator as it consumes a ton of LPG or gas but a diesel generator has not been ruled out yet. If going with a generator we would want an inverter type.Unfortunately those are very rare in 240V. The Honda EU7000 is the one we'd go with but it does not come factory fitted in LPG. Our current Honda is an EU3000 (converted to LPG) but it has a very, very tough time starting the jet pump. We even ran it on ethanol free gas and it still has a very tough time starting the well pump.

Noise is not an issue, except for us, as the nearest neighbor is over 1 mile away with a very thick Maine woods buffer. The current generator is in a dedicated generator hut with marine sound deadening and a through the wall exhaust system. You can't even hear it when standing on the back deck on a dead calm wind free day. Unfortunately the generator has a tough time starting the 1HP 120V jet pump so we are up against a new generator or PV/batteries/inverter once the well is drilled..

The biggest load will be the new 240V well pump (the well guy does not recommend 120V pump). The rest of the house is LPG (fridge/range/Rinnai etc. and all LED lighting.

I would gladly go with LiFePO4, had it on the boat since 2010, but the house is not heated when we are not there and I do not feel comfortable with heating mats that are unattended. Basement temps, even at floor level, can reach -16F as we measured this last winter with a tracking thermometer. This means a big bank of lead acid batteries.

So we currently have three choices:

Bring in underground power - 19.2K to 32.4K are the quotes (this adds tremendous value to the property)

Solar/Inverter/Battery Bank/Wiring/Racks etc. etc. - Even at wholesale cost I am running numbers that are upwards of 16K, while doing it all myself

Generator - Good only for short stays, less than a week, unless diesel. We chewed through three cheap generators (Generac, DuroMax and a Briggs) the Honda EU3000 now has over 4700 hours on it with no sign of quitting but it is currently under powered and the new drilled well is happening at the end of the month which will be 240V..



If you have thoughts on the three paths, or others, or on equipment, please share them. Only quality equipment, with a verifiable track record, is being considered. We've tried the cheap stuff, I own a marine electrical business, and have seen the failures of budget end products such as Renogy, Xantrex etc. and I will not touch it with a 10' pole.

FWIW I do have access to a marine diesel generator, that can be converted to a radiator for cooling, but again it is not a clean sine wave and I would then want to build a line conditioner the upside is that it is free..

Currently there are only a few inverter generators that supply 240V and the Briggs is 100% out of the running, already tried one and it is a total piece of junk, so that, I guess, leaves Honda & Yamaha?
 
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Well/pump - would get the smallest pump you can get away with to fill an above-ground (or basement) cistern with attached pressure tank and 1/2hp jet pump to supply house demand. Submersible well pumps can have crazy surge and can drive the inverter wattage need crazy high. Consider the Grunfos SQ line. They have built in soft start with essentially no surge.

Thoughts are given with no consideration for your actual consumption. It feels kinda low since everything is on Propane, and I would expect you can get a system together for far less than $16K, but I'm going on your numbers.

Option 4:

Assumes favorable net-metering in Maine.

If the low end of $19K gets you grid power, and it enhances the property value by more than that, then it's hard to argue not to do so.

Once grid power is in place, a grid tie system would be cheaper than a full off-grid system as it eliminates the need for batteries, and you would rack up savings while not in use.

That would still leave you without backup in the event of a power failure as grid-tie requires an operational grid. Generator for infrequent use or a SMALL AC coupled off-grid backup for critical loads. AC coupled inverter establishes the grid for the grid-tie system, so you get solar charging of your batteries from your grid-tie panels.
 
The Honda eu7000 is fuel injected so that make lpg conversion complicated.
Nice generator though.
 
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We have had a bunch of generators, and while the inverter generators may seem to be more efficient, that isn't always the case. Sure if your loads are low (ie you don't really need to run the generator) an inverter generator will be throttled down to a lower RPM vs the noninverter stuck at 1800 RPM (or 3600). We load our generator up really good when we run it, somewhere around 6kw, or 80% power and doing that the inverter generator doesn't have an advantage. I'm a big fan of Onan, especially the older stuff - if you can find a 7.5JB they run nearly forever on LPG or NG and are pretty thrifty at it too. We have had a parade of diesels, 12DJC, 6MDJE, 7.5HDKAL, and 10HDKAG... now we've got the newer inverter diesels the 8HDKAK, and the 3.2HDZAA. Neither of the inverters put out 240V, but if you can forgo the 240V pump your house is easily reconfigurable for 120V only. The very similar 7.5HDKAL (240V) uses the same 3-cylinder Kubota diesel engine as my 8HDKAK but has a standard 4 pole (1800 RPM) generator end with a voltage regulator, vs the permanent magnet bearingless flywheel generator unit on the 8HDKAK with an inverter. At constant 6kw it's a dead heat, they both use the same amount of fuel... but at idle there is no comparison, I just don't run my generator at idle. Why do you say your marine diesel has 'dirty' power? It should be pure old-school analog sine wave.
 
I'm offgrid solar only running with 120V. My deepwell pump is 260' down, it's a Grundfos SQ Series Soft Start, soft starts off with a lower pressure and stages up quickly. It's pushing up 260' to a 50 Gallon pressure tank, then 75' to the house from the Pump/Powerhouse, the cutoff is 45 PSI. never notice a water pressure drop and the inverter never breaks a sweat because it starts @ 500W, then 700W, to 900W, and finishing at 1100W (I can watch it on my Samlex EVO Display). A LOT of solar folks use these Soft Start ones because they are gentle on inverters. Even my 3000W Inverter Genny can run it without a blink. My Well guy recommended them as he installs a lot of them and they survive even in hard water conditions. One thing, they are NOT Cheap but as you posted, that isn't a problem. Check/search reviews and "Grundfos SQ offgrid" etc.


From the sounds of it, the only reason you would have 240V is for the pump, which is not a real requirement IMO. Essentially you only need 120V for general use. A good Inverter/Charger can provide 240V Split Phase and give you the 120V in two legs and take care of you. There is little cost difference between a 120 & 240 Volt unit. Solar, can certainly charge batteries to power the inverter & get you going. NW Maine is not as bad as one may think and properly aimed solar panels can generate quite a bit, a ground mount that is seasonally adjustable can make a huge difference without putting a huge extra cost, giving you more Bang per Buck with the panels. Battery Bank sizing is determined by how much power you think you will use daily and for how much non-generations days power storage you want, (most go with 3 days reserve). Inverter/Charger with built-in ATS (Auto-Transfer) and AGS (AutoGen Start *) is also not that difficult to come by these days. AGS is ideal to have as it can be triggered to start a Genset to recharge the battery bank if/when the batteries reach a preset "low volt" point.
*NB, My Samlex EVO Inverter/Charger can charge the battery bank and provide AC passthrough simultaneously without great effort, most Tier-1 products can do so as well. Victron Products are definitely Tier 1 and Excellent Quality as well.

Check here to see what generators are compatible with Generator Control Start Modules. If you have a Genset that is not on Atkinsons Compatibility lists, no company will support it. They also have specialized models for certain Solar Equipment making it much easier to setup & configure.
Atkinson GCSM here: http://atkinsonelectronics.com/generator/

Their Genset Compatibilty List: (398pg PDF)

Just a thought for you to ponder upon...
A 4000W Solar System (< 16 panels all depends on Watt ratings)
Seasonally adjustable ground mounts. 4 settings, Spring, Summer, Fall & Winter. Helps snow shedding too.
Solar Charge Controller, preferably capable of 250VDC /100A for 48V battery, Stackable ? *
5000W / 48VDC - 240VAC Split Phase Inverter Charger *
* = Depends, Victron can be a combined/modular solution, others vary as well.

48V LFP (LiFePO4) requires 16 Cells to make one battery pack, plus a 16S BMS to manage the cells. Ready Made commercial can be quite pricey but you can get quality. There are "value" prebuilts... you get what you pay for and even then.... You can DIY and get good value for money and more or less get Mid-Ground batteries with Commodity Cells, OR you can buy high end cells and really go nice (IE Winstons, SinoPoly, Calb).

This is the right place to ask questions, get answers, find known good reliable vendors & more. Take your time, use your critical thinking and never impulse buy anything... there are always good deals to be had.

Hope it Helps, Good Luck
Steve
 
I'm offgrid solar only running with 120V. My deepwell pump is 260' down, it's a Grundfos SQ Series Soft Start, soft starts off with a lower pressure and stages up quickly. It's pushing up 260' to a 50 Gallon pressure tank, then 75' to the house from the Pump/Powerhouse, the cutoff is 45 PSI. never notice a water pressure drop and the inverter never breaks a sweat because it starts @ 500W, then 700W, to 900W, and finishing at 1100W (I can watch it on my Samlex EVO Display). A LOT of solar folks use these Soft Start ones because they are gentle on inverters. Even my 3000W Inverter Genny can run it without a blink. My Well guy recommended them as he installs a lot of them and they survive even in hard water conditions. One thing, they are NOT Cheap but as you posted, that isn't a problem. Check/search reviews and "Grundfos SQ offgrid" etc.


From the sounds of it, the only reason you would have 240V is for the pump, which is not a real requirement IMO. Essentially you only need 120V for general use. A good Inverter/Charger can provide 240V Split Phase and give you the 120V in two legs and take care of you. There is little cost difference between a 120 & 240 Volt unit. Solar, can certainly charge batteries to power the inverter & get you going. NW Maine is not as bad as one may think and properly aimed solar panels can generate quite a bit, a ground mount that is seasonally adjustable can make a huge difference without putting a huge extra cost, giving you more Bang per Buck with the panels. Battery Bank sizing is determined by how much power you think you will use daily and for how much non-generations days power storage you want, (most go with 3 days reserve). Inverter/Charger with built-in ATS (Auto-Transfer) and AGS (AutoGen Start *) is also not that difficult to come by these days. AGS is ideal to have as it can be triggered to start a Genset to recharge the battery bank if/when the batteries reach a preset "low volt" point.
*NB, My Samlex EVO Inverter/Charger can charge the battery bank and provide AC passthrough simultaneously without great effort, most Tier-1 products can do so as well. Victron Products are definitely Tier 1 and Excellent Quality as well.

Check here to see what generators are compatible with Generator Control Start Modules. If you have a Genset that is not on Atkinsons Compatibility lists, no company will support it. They also have specialized models for certain Solar Equipment making it much easier to setup & configure.
Atkinson GCSM here: http://atkinsonelectronics.com/generator/

Their Genset Compatibilty List: (398pg PDF)

Just a thought for you to ponder upon...
A 4000W Solar System (< 16 panels all depends on Watt ratings)
Seasonally adjustable ground mounts. 4 settings, Spring, Summer, Fall & Winter. Helps snow shedding too.
Solar Charge Controller, preferably capable of 250VDC /100A for 48V battery, Stackable ? *
5000W / 48VDC - 240VAC Split Phase Inverter Charger *
* = Depends, Victron can be a combined/modular solution, others vary as well.

48V LFP (LiFePO4) requires 16 Cells to make one battery pack, plus a 16S BMS to manage the cells. Ready Made commercial can be quite pricey but you can get quality. There are "value" prebuilts... you get what you pay for and even then.... You can DIY and get good value for money and more or less get Mid-Ground batteries with Commodity Cells, OR you can buy high end cells and really go nice (IE Winstons, SinoPoly, Calb).

This is the right place to ask questions, get answers, find known good reliable vendors & more. Take your time, use your critical thinking and never impulse buy anything... there are always good deals to be had.

Hope it Helps, Good Luck
Steve
You do give a lot of useful details. Can you please give me a head start on making your own battery pack including the bms, how involving is it, what are the risks, and how much cheaper can it get?
Thanks in advance for the advice and information
 
Depending on your needs, a small lead battery and an inverter with pass through assist function may allow you to start and run a larger AC motor.
 
So the property in question is on about 300 acres in Northwest Maine. The house is wired for 240V but power was never brought into the structure due to the 2/3 mile long driveway and the cost CMP used to charge to run a private line.

Until last winter the house was fed via a gravity feed hand dug-well from the 1700's (it's old farm property). Over 1/4 mile of poly pipe was trenched through the thick woods to the well and it seems to have frozen, somwwhere, and we can no longer keep a gravity prime on it. It used to gravity-feed and now we need a jet pump in the basement to get any water.

Rather than re-visit more than 1/4 mile of trenching we are going to drill a well. I don't expect it to be too deep, tons of natural springs on the property, but we will need to be running this off batteries and an inverter or a generator or suck it up and bring in underground power.. We don't like the idea of a standard generator as it consumes a ton of LPG or gas but a diesel generator has not been ruled out yet. If going with a generator we would want an inverter type.Unfortunately those are very rare in 240V. The Honda EU7000 is the one we'd go with but it does not come factory fitted in LPG. Our current Honda is an EU3000 (converted to LPG) but it has a very, very tough time starting the jet pump. We even ran it on ethanol free gas and it still has a very tough time starting the well pump.

Noise is not an issue, except for us, as the nearest neighbor is over 1 mile away with a very thick Maine woods buffer. The current generator is in a dedicated generator hut with marine sound deadening and a through the wall exhaust system. You can't even hear it when standing on the back deck on a dead calm wind free day. Unfortunately the generator has a tough time starting the 1HP 120V jet pump so we are up against a new generator or PV/batteries/inverter once the well is drilled..

The biggest load will be the new 240V well pump (the well guy does not recommend 120V pump). The rest of the house is LPG (fridge/range/Rinnai etc. and all LED lighting.

I would gladly go with LiFePO4, had it on the boat since 2010, but the house is not heated when we are not there and I do not feel comfortable with heating mats that are unattended. Basement temps, even at floor level, can reach -16F as we measured this last winter with a tracking thermometer. This means a big bank of lead acid batteries.

So we currently have three choices:

Bring in underground power - 19.2K to 32.4K are the quotes (this adds tremendous value to the property)

Solar/Inverter/Battery Bank/Wiring/Racks etc. etc. - Even at wholesale cost I am running numbers that are upwards of 16K, while doing it all myself

Generator - Good only for short stays, less than a week, unless diesel. We chewed through three cheap generators (Generac, DuroMax and a Briggs) the Honda EU3000 now has over 4700 hours on it with no sign of quitting but it is currently under powered and the new drilled well is happening at the end of the month which will be 240V..



If you have thoughts on the three paths, or others, or on equipment, please share them. Only quality equipment, with a verifiable track record, is being considered. We've tried the cheap stuff, I own a marine electrical business, and have seen the failures of budget end products such as Renogy, Xantrex etc. and I will not touch it with a 10' pole.

FWIW I do have access to a marine diesel generator, that can be converted to a radiator for cooling, but again it is not a clean sine wave and I would then want to build a line conditioner the upside is that it is free..

Currently there are only a few inverter generators that supply 240V and the Briggs is 100% out of the running, already tried one and it is a total piece of junk, so that, I guess, leaves Honda & Yamaha?
I am curious as to what you decided to do. I am off-grid down here in NH. The utility wanted $11/ft for power so for 1500ft about $17,000. I decided to go off grid.
 
I am curious as to what you decided to do. I am off-grid down here in NH. The utility wanted $11/ft for power so for 1500ft about $17,000. I decided to go off grid.
I always thought that was all there was to it, if power was available you could have it. After paying for the pole, all the associated wiring and cabling, inspections by the power company and an electrician, and the power company stringing line the county planning office when they came around do sign off on the completion of my permit to put in power... didn't. Refused to give me a green sticker, and after almost 2 years of exhausting every bit of influence I could bring to bear on them, I gave up. I want to buy power, the power company wants to sell it to me - but the county says I can't have it. Now, 3-years later I'm so glad they didn't as I pay a fraction of what my power bill used to be and I'm not subject to blackouts. I did ask myself before I purchased the stuff for my final system what was the worst thing that could happen after spending all this money to put in solar, they let me have power, or MAKE me hook to the power? So I made sure that my system would happily spin a meter backward all summer long in a grid-tie configuration should that happen. A couple of dollars more, but I'm glad (for my peace of mind) that I did it that way - off-grid with a system also capable of grid-tie.
 
So the property in question is on about 300 acres in Northwest Maine. The house is wired for 240V but power was never brought into the structure due to the 2/3 mile long driveway and the cost CMP used to charge to run a private line.

How much to have utility drop to the edge of your property?
How much to trench the 2/3 mile yourself and put in conduit with wire?

Even if you skimped on wire gauge to save on copper, it could keep an inverter/charger with battery charged up, and surge currents would come from battery.
 
Depending on your needs, you could even get a high voltage buried cable (300V per line, 600V L-L) and then install a transformer at the destination. I know that buried 300V lines are often used for small oil derrick/pumps and some irrigation engines in farm country. Given the length of the run, it may be cheaper copper wise.
 
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the county planning office when they came around do sign off on the completion of my permit to put in power... didn't. Refused to give me a green sticker, and after almost 2 years of exhausting every bit of influence I could bring to bear on them, I gave up.
Did they give you a reason for refusing?
 
I always thought that was all there was to it, if power was available you could have it. After paying for the pole, all the associated wiring and cabling, inspections by the power company and an electrician, and the power company stringing line the county planning office when they came around do sign off on the completion of my permit to put in power... didn't. Refused to give me a green sticker, and after almost 2 years of exhausting every bit of influence I could bring to bear on them, I gave up. I want to buy power, the power company wants to sell it to me - but the county says I can't have it. Now, 3-years later I'm so glad they didn't as I pay a fraction of what my power bill used to be and I'm not subject to blackouts. I did ask myself before I purchased the stuff for my final system what was the worst thing that could happen after spending all this money to put in solar, they let me have power, or MAKE me hook to the power? So I made sure that my system would happily spin a meter backward all summer long in a grid-tie configuration should that happen. A couple of dollars more, but I'm glad (for my peace of mind) that I did it that way - off-grid with a system also capable of grid-tie.
Boy am i curious. What was the reason they refused to sign off on the job?
 
He said according to the county records his house was in the middle of a river. Which is a considerable distance behind his house.

 
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