Bulletproof Off-grid System Recommendations?

[Brooklyndodger]

Hi,

I have been researching DIY solar for a few weeks now as I am contemplating installing a full solar power system in my off-grid seasonal cabin, and I'm hoping to get some candid feedback from this community.

Then more I research relatively inexpensive all-in-one units from Growatt, EG4, Mpp, etc., the more they seem finicky and prone to failure. Will's last couple video reviews are a case in point.

I'm looking for a system that is very reliable, and I want to spend a minimum amount of time troubleshooting equipment or software issues, especially since I do not and will not have Internet or cell service at the cabin. The whole project is aimed at making my life simpler, not more complicated.

This seems to be leading me to Victron or Morningstar even though system design and initial installation seems more complicated. The Morningstar components seem especially robust, but their "industrial" focus is a bit intimidating.

FYI, I'm aiming for a system with 4-5KW solar, 5kwh max daily usage, 15-20 kwh lithium battery bank.

For me, simplicity = reliability, and as a newbie to this, I'd appreciate some frank guidance from those of you with experience building these systems. Thanks in advance!

 

[sunshine_eggo]

Hi,

I have been researching DIY solar for a few weeks now as I am contemplating installing a full solar power system in my off-grid seasonal cabin, and I'm hoping to get some candid feedback from this community.

Then more I research relatively inexpensive all-in-one units from Growatt, EG4, Mpp, etc., the more they seem finicky and prone to failure. Will's last couple video reviews are a case in point.

I'm looking for a system that is very reliable, and I want to spend a minimum amount of time troubleshooting equipment or software issues, especially since I do not and will not have Internet or cell service at the cabin. The whole project is aimed at making my life simpler, not more complicated.

This seems to be leading me to Victron or Morningstar even though system design and initial installation seems more complicated. The Morningstar components seem especially robust, but their "industrial" focus is a bit intimidating.

FYI, I'm aiming for a system with 4-5KW solar, 5kwh max daily usage, 15-20 kwh lithium battery bank.

For me, simplicity = reliability, and as a newbie to this, I'd appreciate some frank guidance from those of you with experience building these systems. Thanks in advance!

Your stated goals require investment. You've landed on Victron as an option, so you are looking in the right place. I vigorously recommend Victron because they are extremely reliable, and they help make sure I don't have any hip issues from my wallet being too heavy.

While not online, the system has great potential for easy and convenient remote monitoring and full control.

Detailed DIY deployments can be a little hairy, but you really learn the system. If you just want to hook things up and turn them on, it can go very quickly. If you want to fully integrate them including communication with battery BMS. If you go with a full Victron Eco System, you may find yourself searching for options to get you online.

It's a personal comfort for me to be able to see my system from 3.5 hours away and where I'm 20°F warmer than the site.

A particularly nice feature is their MPPT can be powered by PV once the battery voltage is set. So even if you have some catastrophe where the batteries go offline, the PV can still provide limited power to the system and can provide a charge voltage to batteries that may need to be woken up (BMS offline).

Your base specs seem fairly robust.

Have you reviewed your available solar?
Have you conducted a detailed energy audit?
Do you expect the same consumption even when offsite?

 

[Brooklyndodger]

Your stated goals require investment. You've landed on Victron as an option, so you are looking in the right place. I vigorously recommend Victron because they are extremely reliable, and they help make sure I don't have any hip issues from my wallet being too heavy.

While not online, the system has great potential for easy and convenient remote monitoring and full control.

Detailed DIY deployments can be a little hairy, but you really learn the system. If you just want to hook things up and turn them on, it can go very quickly. If you want to fully integrate them including communication with battery BMS. If you go with a full Victron Eco System, you may find yourself searching for options to get you online.

It's a personal comfort for me to be able to see my system from 3.5 hours away and where I'm 20°F warmer than the site.

A particularly nice feature is their MPPT can be powered by PV once the battery voltage is set. So even if you have some catastrophe where the batteries go offline, the PV can still provide limited power to the system and can provide a charge voltage to batteries that may need to be woken up (BMS offline).

Your base specs seem fairly robust.

Have you reviewed your available solar?
Have you conducted a detailed energy audit?
Do you expect the same consumption even when offsite?

Thanks very much for the detailed reply. You confirm my suspicions!

Yes, I've done an energy/solar audit and those figures are designed for max usage and three days autonomy during October in my area, which is the latest we will be there.

Unfortunately, remote monitoring will not be an option since there will be no Internet access from the cabin. The system will be shut down completely from November-April.

I did not know that about Victron's MPPT flexibility. Thanks for that.

It would be great if Will would do some more Victron system videos -- they're great for giving you confidence!

 

[John Frum]

FYI, I'm aiming for a system with 4-5KW solar, 5kwh max daily usage, 15-20 kwh lithium battery bank.

To size the inverter we need to know your max draw?
Please consider that motor loads may have a locked rotors amps rating that can be 3 to 7 times their nameplate rating.

 

[mvonw]

I just did a major DIY Solar upgrade to my 100% Off-Grid cabin. I went with a SolArk 12k and Trophy batteries and a Honda 7000is gas generator as backup or battery charging on low solar periods. I cannot recommend the sol ark enough. It was SUPER simple to set up, and it has been rock solid, even for a noob like me. A lot of my design decisions were informed by my snowy/cold location and need. For me, the best thing has been the ground mounted bifacial 12kw array. It produces a lot of power from snow reflection when the front of the panels are covered. Frankly, my biggest cost was building a nice insulated power shed to house the batteries, inverter, etc.

I’m sure Victron is great, but it’s a more complex platform, but definitely flexible.

 

[sunshine_eggo]

Thanks very much for the detailed reply. You confirm my suspicions!

Yes, I've done an energy/solar audit and those figures are designed for max usage and three days autonomy during October in my area, which is the latest we will be there.

Unfortunately, remote monitoring will not be an option since there will be no Internet access from the cabin. The system will be shut down completely from November-April.

I did not know that about Victron's MPPT flexibility. Thanks for that.

It would be great if Will would do some more Victron system videos -- they're great for giving you confidence!

He has a pretty decent one:

I would not be comfortable with completely shutting down for 5 months. I would be inclined to allow the MPPT to maintain the battery at a lower float voltage around 3.275/cell.

If you have cell phone access in the area, a cheap phone with a hot spot might be worth it... Victron also has LTE solutions.

 

[Brooklyndodger]

I just did a major DIY Solar upgrade to my 100% Off-Grid cabin. I went with a SolArk 12k and Trophy batteries and a Honda 7000is gas generator as backup or battery charging on low solar periods. I cannot recommend the sol ark enough. It was SUPER simple to set up, and it has been rock solid, even for a noob like me. A lot of my design decisions were informed by my snowy/cold location and need. For me, the best thing has been the ground mounted bifacial 12kw array. It produces a lot of power from snow reflection when the front of the panels are covered. Frankly, my biggest cost was building a nice insulated power shed to house the batteries, inverter, etc.

I’m sure Victron is great, but it’s a more complex platform, but definitely flexible.

That's great to hear. It looks like SolArk has a 5k option as well. It seems like my system requirements are about half of yours all around, so that may be a great option. I was definitely thinking ground mount bi-facials for my set up as well. I'm very interested in your power shed -- do you detail that in a separate thread?

 

[sunshine_eggo]

That's great to hear. It looks like SolArk has a 5k option as well. It seems like my system requirements are about half of yours all around, so that may be a great option. I was definitely thinking ground mount bi-facials for my set up as well. I'm very interested in your power shed -- do you detail that in a separate thread?

The lowest part of bifacials need to be 1m above the mounting surface to maximize backside performance.

 

[Brooklyndodger]

He has a pretty decent one:

I would not be comfortable with completely shutting down for 5 months. I would be inclined to allow the MPPT to maintain the battery at a lower float voltage around 3.275/cell.

If you have cell phone access in the area, a cheap phone with a hot spot might be worth it... Victron also has LTE solutions.

I hear you but am concerned about temps dropping below 0 degrees C and would rather avoid the complication of a heating pad/box if possible.

 

[SparkyJJO]

I think that's really only an issue if you're trying to charge. The cells won't be damaged by sitting a little below 0C for a while if they're not being charged. But, what is the absolute coldest it will get?

Alternatively, is it at all reasonable to take the LFP batteries with you when you leave?

 

[mvonw]

My place gets as cold as -30F sometimes, with mid winter temps usually in the single digits. I built an insulated cabinet for my 6 Trophy 120Ah batteries to overwinter in. I have an InkBird thermostatically controlled power strip that runs a 200 watt heater set to run at 50F. So far, it only has to run an hour or two each day to keep the batteries at a happy temperature. The Trophy batteries have built in heaters too, but I consider that as a backup if the primary heating fails. The key is getting everything insulated enough. You really don’t need a lot of power if you have that..

 

[sunshine_eggo]

I hear you but am concerned about temps dropping below 0 degrees C and would rather avoid the complication of a heating pad/box if possible.

Low temp charging protection exists at the battery level and at the charger level. If you think it may NEVER get above freezing, then yeah... Shut 'em down.

Our spot up north is running pretty cold right now, but I usually get a couple of hours of > 8°C for charging. The Victron system + BMS interface (Batrium) allows me to disable charging, but enable PV to run loads, so from 3-7°C, no charging, but MPPT power loads. 8°C+, and I get charging. There was one day I got 0 and another where it didn't' heat up until shortly before the charging hours were over.

 

[Brooklyndodger]

I think that's really only an issue if you're trying to charge. The cells won't be damaged by sitting a little below 0C for a while if they're not being charged. But, what is the absolute coldest it will get?

Alternatively, is it at all reasonable to take the LFP batteries with you when you leave?

I would rather not move the batteries seasonally, and don't have a place to store them in my apartment . I think I will either completely shut them down or take the plunge and build a heater box and keep the system up.

 

[Brooklyndodger]

Low temp charging protection exists at the battery level and at the charger level. If you think it may NEVER get above freezing, then yeah... Shut 'em down.

Our spot up north is running pretty cold right now, but I usually get a couple of hours of > 8°C for charging. The Victron system + BMS interface (Batrium) allows me to disable charging, but enable PV to run loads, so from 3-7°C, no charging, but MPPT power loads. 8°C+, and I get charging. There was one day I got 0 and another where it didn't' heat up until shortly before the charging hours were over.

It's true, I could trust in the dual low temp charging protection and just let it do its thing...

 

[John Frum]

A root cellar will keep things above freezing.

 

[rkymtnoffgrd]

16 years ago i put 1000w on my off grid cabin at 10k in the colorado rockies... I put a grundfos sq variable speed pump in the 150' well that could softstart and operate on wide range of ac or dv voltage (including 115). This allowed me singlestack one Outback 3500 inverter with a single outback charge controller. I ran off 8 T-105s. It also powered an apartment sized kenmore energystar refrigerator wash/dryer and all small house loads (think LED lights, Led tv ect). The waterhearter was a bosh aquastar (propane) and stove and dryer ran off propane too. Honda EU2000 was the backup. That simple system was bulletproof. In the 16 years I changed the batteries 1x after original install (every 7 years) and never had an issue. Never did a firmware update or anything. The stove and wtr htr would only consume about 100lb propane cylinder in an entire year. This was a summer and winter holiday cabin only. We did not live there but were there probably 60-80 days per year. I originally planned on 3000w on that charge controller, but I never did it becasue I really didnt need it... I had plenty of power during the summer. I did all the work myself, and that system brought great pride and reward over thoese years. Last year I sold that little cabin, but the system will likely continue to perform for another decade. Rethink your load, simplicity begins with eliminating unnecessary equipment. I dont know enough about the newer inverters, the generation of outback inverters from the 2006 era were bulletproof...

 

[x98myers7]

SolArk is definitely the best and comes with the corresponding price tag. I think a separate component system might be better unless you have the budget to support AiO price tags.

two Midnite classic SCCs and a Samlex inverter will probably be less than half or a third the cost of a SolArk. all are UL listed so good to go for residential install in the USA. plus, Midnite classics have built in AFCI and GFP which are important features to have for safety.

 

[Koldsimer]

Schneider Inverters- Proven 20+ year design that is as bulletproof as an inverter can get. Unparalleled Surge capabilities.

Midnite charge Controllers- another product that has been around for some time but they just plain work and are built like a tank. Hyper-VOC is a great feature.

SOK 48v batteries- extremely nice server rack option that has some great features.

I run all three of these and couldn't be happier. Totally off grid for nearly 3 years without a hiccup!

 

[Brooklyndodger]

SolArk is definitely the best and comes with the corresponding price tag. I think a separate component system might be better unless you have the budget to support AiO price tags.

two Midnite classic SCCs and a Samlex inverter will probably be less than half or a third the cost of a SolArk. all are UL listed so good to go for residential install in the USA. plus, Midnite classics have built in AFCI and GFP which are important features to have for safety.

Thanks, will check out Midnite and Samlex.

 

[Brooklyndodger]

16 years ago i put 1000w on my off grid cabin at 10k in the colorado rockies... I put a grundfos sq variable speed pump in the 150' well that could softstart and operate on wide range of ac or dv voltage (including 115). This allowed me singlestack one Outback 3500 inverter with a single outback charge controller. I ran off 8 T-105s. It also powered an apartment sized kenmore energystar refrigerator wash/dryer and all small house loads (think LED lights, Led tv ect). The waterhearter was a bosh aquastar (propane) and stove and dryer ran off propane too. Honda EU2000 was the backup. That simple system was bulletproof. In the 16 years I changed the batteries 2x... (every 7 years) and never had an issue. Never did a firmware update or anything. The stove and wtr htr would only consume about 100lb propane cylinder in an entire year. This was a summer and winter holiday cabin only. We did not live there but were there probably 60-80 days per year. I originally planned on 3000w on that charge controller, but I never did it becasue I really didnt need it... I had plenty of power during the summer. I did all the work myself, and that system brought great pride and reward over thoese years. Last year I sold that little cabin, but the system will likely continue to perform for another decade. Rethink your load, simplicity begins with eliminating unnecessary equipment. I dont know enough about the newer inverters, the generation of outback inverters from the 2006 era were bulletproof...

That sounds like a success story to me. I also have a gundfos soft start well pump currently in place. We run a propane stove, water heater and refrigerator and use about 100-125 gallons of propane a year with our seasonal usage. Totally hear you about keeping power needs modest and simplicity. As my kids will begin using the cabin on their own, I think I want electric lighting for sure. I also want to build in the capability of an electric fridge in the future, ceiling fans, filling my basement cistern from the well without running the generator, and the ability to run shop tools. It adds up quick...but determined to keep it below 5kw max.

 

[Casteil]

16 years ago i put 1000w on my off grid cabin at 10k in the colorado rockies...

I had plenty of power during the summer. I did all the work myself, and that system brought great pride and reward over thoese years. Last year I sold that little cabin, but the system will likely continue to perform for another decade.

Good read! Bittersweet, but I hope I'm also able to look back in 10-20 years and feel this whole solar power thing was worthwhile (and not an ongoing hassle).

I also want to build in the capability of an electric fridge in the future

For a cabin, probably worth looking into a DC refrigerator, fwiw. Full-size AC refrigerators meant for use in houses consume a pretty ridiculous amount of power by comparison.

 

[Bluedog225]

rkymtnoffgrd-I miss your cabin ?. It’s perfect.

 

[bfitzgerald]

Hi,

I have been researching DIY solar for a few weeks now as I am contemplating installing a full solar power system in my off-grid seasonal cabin, and I'm hoping to get some candid feedback from this community.

Then more I research relatively inexpensive all-in-one units from Growatt, EG4, Mpp, etc., the more they seem finicky and prone to failure. Will's last couple video reviews are a case in point.

You are probably a good candidate for Victron although I am pretty much all Conext, aka Schneider. I will be adding some Victron to my setup this year as I add 15 kwh of LFP to my existing batteries. I suggest you think about your system DC voltage. I don't think that anyone putting in an all new off grid system should consider anything but a 48 v system.

I'm looking for a system that is very reliable, and I want to spend a minimum amount of time troubleshooting equipment or software issues, especially since I do not and will not have Internet or cell service at the cabin. The whole project is aimed at making my life simpler, not more complicated.

This seems to be leading me to Victron or Morningstar even though system design and initial installation seems more complicated. The Morningstar components seem especially robust, but their "industrial" focus is a bit intimidating.

FYI, I'm aiming for a system with 4-5KW solar, 5kwh max daily usage, 15-20 kwh lithium battery bank.

Seasonal use only in the summer? Off season usage? Where are you located? My off grid cabin is in northern Saskatchewan (55 degrees N) so in the summer I get lots of sun. We use about 11 kwh per day and our 4 kwh array provides 98% of the power we need. We live at the cabin full time from mid-May to mid-October. I probably run the generator for less than 5 - 10 hours total all summer and sometimes I run it so that I can put fresh fuel in and make sure it works. Currently I have a 40 kwh FLA battery bank, but, as I mentioned above, I am going to introduce 15 kwh of LFP this spring.

For me, simplicity = reliability, and as a newbie to this, I'd appreciate some frank guidance from those of you with experience building these systems. Thanks in advance!

There is a lot of cool new stuff out there to choose from and if you can and will DIY your system you will learn enough to be self supporting. I designed and installed my own off grid system back in 2012. I am glad that I took the time to do it. I really have not had any problem that I could not immediately diagnose and fix. You are on a good path, this forum is great for DIYers. Another forum worth mentioning is Northern Arizona Wind and Sun's forum. I used that a lot since this site didn't exist back then. This stuff is not real hard to figure out but mistakes can be expensive. Don't cheap out on safety!

 

[mvonw]

That sounds like a success story to me. I also have a gundfos soft start well pump currently in place. We run a propane stove, water heater and refrigerator and use about 100-125 gallons of propane a year with our seasonal usage. Totally hear you about keeping power needs modest and simplicity. As my kids will begin using the cabin on their own, I think I want electric lighting for sure. I also want to build in the capability of an electric fridge in the future, ceiling fans, filling my basement cistern from the well without running the generator, and the ability to run shop tools. It adds up quick...but determined to keep it below 5kw max.

Once I electrified my cabin I was able to use electric for refrigeration, starlink, a TV, power tools, electric blankets, lights and a lot things. I cook now a lot with an induction hot plate to save on propane. I use propane now exclusively for heating,

 

[bfitzgerald]

Good read! Bittersweet, but I hope I'm also able to look back in 10-20 years and feel this whole solar power thing was worthwhile (and not an ongoing hassle).



For a cabin, probably worth looking into a DC refrigerator, fwiw. Full-size AC refrigerators meant for use in houses consume a pretty ridiculous amount of power by comparison.

I would not bother with a DC fridge. A good Energy Star a/c fridge, even a big one isn't a big deal anymore. A bit over 1 kwh per day. I run two large fridges 21', 19' and a 10 cu ft. deep freeze on 4000 kw array. The array also provides enough power to run my dish washer, make most of my hot water, microwave, coffee maker, electric kettle, Starlink, 240 volt submersible water pump, log splitter, 60 " big screen TV, Bell TV Satellite receiver, stereo, all my power tools, countless (it seems) laptops, cell phones and tablets No problem. I haven't shopped around but I just looked up a Danzer 10 cu ft 24v dc fridge for a mere $2340. Buy a few more panels and get a great fridge. Maybe even get the icemaker option!