Off Grid System Design - Issues/Suggestions?

[jordanregier]

Hello all!

We recently purchased a cabin in the Parry Sound area (Ontario, Canada) and are looking to go solar and mitigate the need to run our generator (5500w yamaha). The cabin is typically used 3-4 days once per month and for a week twice a year.

I have been researching for a couple of weeks now and believe I have spec'd out my system but before I start purchasing the components I wanted to get some feedback.

Key Requirements:
1) System that can often power our requirements (1500Wh/day) - I am okay running the generator if we have multiple days of no sun
2) Budget - $3000 CAD
3) Expandable if we find the cabin is used more often or we require more solar power

System Components:
1) 3x Renogy Eclipse 100w panels ($500 cash - new in box)
2) 4x 6V Crown CR-205s - 410ah total storage ($140ea - $630 tax inc)
3) xantrex freedom sw3012 12 volt 3000 watt inverter charger ($1000 cash - used)
4) Renogy Rover 40amp MPPT controller - ($200 tax inc)
5) Misc components (cables/fuses/DIY panel mounts etc) ($500)

Do you guys see any major issues with this plan given my requirements? Any alternatives you would suggest?

 

[Bubba1]

I would look for larger used panels if possible. Probably save 2 or 3 hundred.

 

[AgroVenturesPeru]

Hello all!

We recently purchased a cabin in the Parry Sound area (Ontario, Canada) and are looking to go solar and mitigate the need to run our generator (5500w yamaha). The cabin is typically used 3-4 days once per month and for a week twice a year.

I have been researching for a couple of weeks now and believe I have spec'd out my system but before I start purchasing the components I wanted to get some feedback.

Key Requirements:
1) System that can often power our requirements (1500Wh/day) - I am okay running the generator if we have multiple days of no sun
2) Budget - $3000 CAD
3) Expandable if we find the cabin is used more often or we require more solar power

System Components:
1) 3x Renogy Eclipse 100w panels ($500 cash - new in box)
2) 4x 6V Crown CR-205s - 410ah total storage ($140ea - $630 tax inc)
3) xantrex freedom sw3012 12 volt 3000 watt inverter charger ($1000 cash - used)
4) Renogy Rover 40amp MPPT controller - ($200 tax inc)
5) Misc components (cables/fuses/DIY panel mounts etc) ($500)

Do you guys see any major issues with this plan given my requirements? Any alternatives you would suggest?

How many people when you say "we"?

First glance, I would say 1.5kwh/day is an unrealistically low expectation. Unless you're planning on barbecuing everyday or cooking with gas. Will there be a refrigerator?

I'm not familiar with those batteries. My only suggestion would be to try and find lithium iron phosphate batteries. Since you'll only be around every once in a while, you wouldn't have to worry about self-discharge when not there, but you will have to keep them above freezing.

The advantage of being in that part of the world apparently is that you don't have to worry about theft. I know if I left that system for that length of time where I live, most (if not all) of it would be gone by the time I came back.

 

[jordanregier]

Bubba1 - How many watts do you think would be best for this system?

ArgoVenturesPeru - Typically 3 people. The batteries are 6V flooded lead acid... I would like Lithium batteries but that will bow my budget and I dont have a good idea how I would keep them above freezing in the winter.

We have a propane stove and fridge, the fridge does require 12V to power the ignitor. Here are my estimates:


I am unsure what would be best to power the 12v water pump and fridge... I have a couple cheap 100w solar packages from Canadian Tire maintaining deep cycle batteries that are running those. Do I leave that or convert 120V back to 12V or can I pull 12V directly off the battery bank before going into the inverter?

 

[MichaelK]

Do NOT buy 12V solar panels. They are waste of money. I can buy 1000W of grid-tie panels cheaper than you can buy 3 100W panels.

I would also recommend skipping 12V and go straight to 24V. The controller will be happier with lower amperage.

Your consumption numbers do not look realistic. A freezer that consumes only 250W per day? I would double your expectations and plan on making 3kWh per day. With 1000W of panels, 3kWh per day is very doable.

I can't recommend Renogy to anyone anymore. Look at Epever's 50A MPPT. That has a far higher Voc maximum. Or, buy a quality controller, like a MorningStar, Midnight, or Outback.

I could put together a 1000W system cheaper than your 300W system.

 

[iamrich]

System Components:
1) 3x Renogy Eclipse 100w panels ($500 cash - new in box)
2) 4x 6V Crown CR-205s - 410ah total storage ($140ea - $630 tax inc)
3) xantrex freedom sw3012 12 volt 3000 watt inverter charger ($1000 cash - used)
4) Renogy Rover 40amp MPPT controller - ($200 tax inc)
5) Misc components (cables/fuses/DIY panel mounts etc) ($500)

If you are going off grid completely and don't need city permits, go used panels. I think you can get used Trina panels from Santan for $50 each ($250 in shipping to Canada?). $550 would likely get you at least six panels (1500w) I would stretch it and see if you can get nine panels ($700). I don't know anything about the batteries, but you can afford what you need in LiFePo IMO, so they will have to do. I would run an all in one (LV2424 or Growatt 3k). I don't see anything that has big surge so you should be fine with a 2-3k watt inverter.

1 9 250w Panels $700 USD
2 batteries $500 USD
3+4 All in one $6-700 USD
5 Racking misc $400 USD

$2300 USD ($3000 CD Eh?)

That gives you 2250 watts of panels (over panelled) going into a 2400-3000w invert, and even in crappy 2 hour sun if you run the batteries at 24v you will can charge at 100a, and you have 4000+ watts to play with.

 

[jordanregier]

Thanks for the responses!

Panels - Sounds like I need to up my panel array, shoot for 1000W and add if necessary. I will look at those suppliers in the US.
MPPT - Do you guys think it's worth the extra $$ to get a victron controller? Bluetooth and not needing a separate controller in the cabin would be nice. Victron or Epever... I will go with 50amp.
Inverter - Other than the growatt and LV2424, recommendations for around the $1000 inverter/chargers for this system?
Batteries - How many total AH @ 24v would you recommend?

 

[Steve_S]

We can't get sweet deals like SantanSolar in the US but we do have this here near you:
https://www.solarshoppingmall.com/24V-Solar-Panel_c_25.html

For solar/inverter etc, I'd suggest a Growatt All-in-One unit, nothing wrong with Victron at all, they are Tier-1 but the $ goes with that too.
There is a lot to be said for KISS especially on a Part-Timer system.
I would consider nothing lower than a 120VAC/2000W but TBH 3000W would be better because once you have the convenience of actual power available, you'll end up using more than you think. Lessons Learned by MANY (ie most people actually).

2.0kWh per day @ 24VDC = 83.333 Ah or 249.99AH with 3 days runtime.
A single 24V/280AH Battery assembly would do that quite nicely and would be more than capable of supplying the inverter (3000W@24V = 125A) and accommodate any surge demand as well. Unlike Lead Batteries, you can always add another pack in parallel at a later date if you want to increase battery capacity/storage without ill effect. IT IS HIGHLY RECOMMENDED that if you add additional packs, that they should be close to the same AH Capacity in order to keep the bank balanced during charge/discharge.


ALTERNATIVE OPTION:
Here is a Vendor in Montreal who is more oriented towards the boating/sailing crowd. He has some great deals setup but using "Value" Tier-3 Gear made by Yiyen in China (It is Good Product - but it is Value grade product), it's a good dollar value option. See KITS 13-16 for 120VAC from 24V Battery. French site http://www.energie-abordable.com/Ensemble_pour_chalet.htm There would still be other components like racking for the panels etc to get and the batteries of course.

Battery:
Luyuan's EVE-280AH Grade-A Matched set (8 cells for 24V) = $1020 USD delivered to your door.
1x 250A-8S BMS = $150 +
1x 250A Fuse (MRBF type) = $30 USD
1X Box/Case/Frame for the cells ? depends on what you want.
Link to Luyuan Link, to get a proper quote you MUST open a chat/messenger on Alibaba with Amy.

Luyuan 8pcs 280ah Lifepo4 (lfp) 3.2v Cells Battery (bulk,Voltage & Ir Matched)--newest Version - Buy 3.2v Lithium Iron Phosphate Battery lifepo4 Battery Pack electric Car Battery Pack Product on Alibaba.com

Luyuan 8pcs 280ah Lifepo4 (lfp) 3.2v Cells Battery (bulk,Voltage & Ir Matched)--newest Version - Buy 3.2v Lithium Iron Phosphate Battery lifepo4 Battery Pack electric Car Battery Pack Product on Alibaba.com

szluyuan.en.alibaba.com

Final points for consideration.
Mounting / Racking can be quite expensive and you will need to ensure you get the right solution for your installation.
BOS (Balance of System components) can easily add 25% on top of the main component costs. That's fuses, breakers, wiring etc.
IF you are going to do a Fixed Mount Installation the optimal angle would be 46° or perfect on a 12:12 Pitch Roof (which is 45°)
IF Ground Mounted, allow a MINIMUM of 3' from the bottom of the panels to grade, 4' is better ! You'd be surprised how fast that crap piles up.
IF mounting on a roof, panels must have 6" clearance between roof & panel, be 12" MIn below the Peak and 12" above the bottom edge (this is to prevent wind catching the panels & "stuff" from causing issues.

Link to the table info below: http://www.solarelectricityhandbook.com/solar-calculator.html




Hope it helps fiull in some blanks.
Have a look at the links in my signature, a few will be of help to you as you move forward with your project.
The "About my System" page might also be useful to you, as I am up near Alqonguin Park - small offgrid solar powered.

 

[Diysolar123]

so, how do you handle "snow coverage" on solar panels in canada if nobody is around?
Are the panels motor mounted so they can change angle to vertical so snow falls off and then solar track during the rest of the day?

 

[jordanregier]

Where is everyone in Canada getting the Growatt all-in-one's from? I found the 3k on amazon however can't find it anywhere else, not sure if the price is good (https://www.amazon.ca/Inverter-Charger-Inverters-Growatt-Converter/dp/B08MKS55SM/ref=dp_prsubs_2?pd_rd_i=B08MKS55SM&psc=1). I noticed on the growatt specs the operating temp only goes down to 0 Celcius and -15C for storage... it's likely to get -40 in the winter here... how do keep the unit warm? Keep in mind I will go months in the winter without visiting.

Which panels from the solar shopping mall would you recommend? https://www.solarshoppingmall.com/24V-Solar-Panel_c_25.html . I am thinking 3 in series.

The Luyuan LiPo batteries are out of stock... also unsure how I would keep above freezing what I am not around. Thinking of sticking with the FLA batteries... strong objections? I can get these batteries locally https://batteryguys.com/products/crown-deep-cycle-cr-260. Thinking 4 batteries for 260amp @ 24v. Thoughts?

Regarding the snow on the panels... I am assuming at the 22-degree angle it will shed the snow.

 

[iamrich]

Wondering if you can put the Growatt and batteries in a closet or something with a small heater on a thermostat. If you insulate the heck out of the closet, you probably wont need much heat to keep it above 0.

 

[45North]

Or you could try these guys at Kemptville near Ottawa. They are not taking walk-ins right now but may be good for advice and sales.

Solacity - Canadian Green Power Goods & Great Advice!

YOUR Canadian source for all renewable energy supplies! Buy solar panels, charge controllers, inverters, batteries and more at great prices. We design too!

www.solacity.com

 

[HRTKD]

The Luyuan LiPo batteries are out of stock... also unsure how I would keep above freezing what I am not around. Thinking of sticking with the FLA batteries... strong objections? I can get these batteries locally https://batteryguys.com/products/crown-deep-cycle-cr-260. Thinking 4 batteries for 260amp @ 24v. Thoughts?

LiFePO4 is OK to keep indoors, lead acid is not (unless vented). LiFePO4 does need to be kept above 32° F if you plan to charge them. If you don't plan to use the system during cold months (below 32° F) then you can discharge the LiFePO4 to about 70% and then disconnect them from everything, including the BMS. They'll hold that way for months.

If you do plan to charge the batteries in the cold, then a warming system is necessary. Indoors will be easier, but outdoors can be done. As @iamrich said, you'll want to insulate the battery compartment very well and add a warming system. A number of us have put together our own warming systems for LiFePO4. It is very doable.

 

[Third Rail]

The Luyuan LiPo batteries are out of stock... also unsure how I would keep above freezing what I am not around.

My camp is north of the French River and I will be pulling the trigger on components for a small system shortly. We don't consume a lot of power so it will be an 8s 24V 280 AH LiFePo4 battery bank. What will I do with them for the winter? Simple, at around 47 kg, take them home in November when I shut the camp down and return with them in April. If I need power during my winter visits, I will run my 2KVA inverter generator. Super quiet and sips gas.

 

[Sniper]

Like Steve_S mentioned, I'd reach out to Mark over at S.A.W. Techologies via the Solar Shopping Mall: https://www.solarshoppingmall.com/
He can help with configurations and is good with pricing. Purchase most of my system and off grid appliances from him.

 

[Sniper]

Wondering if you can put the Growatt and batteries in a closet or something with a small heater on a thermostat. If you insulate the heck out of the closet, you probably wont need much heat to keep it above 0.

Insulated rigid foam box with small 10-15 watt incandescent light bulb hooked up for a thermostat works.

 

[jordanregier]

I found a growatt SPF 3000 for $1250 CAD cash and 310w Canadian Solar panels (CS6X 310P) for $175 CAD cash. Planning on 4 panels, the growatt and 100AH lifepo4 or 200AH FLA. Sound good?

A question on the growatt - I dont see that it includes a battery temperature sensor... is this a problem?

 

[HRTKD]

A question on the growatt - I dont see that it includes a battery temperature sensor... is this a problem?

Less of a problem if you implement a battery warming system for LiFePO4. Even less if you go with FLA.

 

[iamrich]

I found a growatt SPF 3000 for $1250 CAD cash

That seems really high? I thought these units normally go for $700 USD ($875CAD)?

 

[45North]

That seems really high? I thought these units normally go for $700 USD ($875CAD)?

I have no idea what the Growatt sells for up here.
But as a general comment on prices, it's more complicated than simply converting our currency.

• The population and market is only 10% and spread out over a big area.
• Also we don't have economies of scale.
• Also we have higher social welfare and hence taxes.

And sometimes it seems we're just plain getting ripped off! (But that's a different rant, LOL. Like our cell and internet providers!)