Small Cabin

# Posted: 21 Feb 2025 04:35pm
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Good day all: I'm wondering if my current system will allow me to run a conventional electric refrigerator. I'm so tired of my propane fridge blowing out, not to mention getting propane to our remote location. My calcs say that summer should be fine but I have concerns about the fall. Our off-grid camp in northern Ontario, Canada where we live for the 6 warm months of the year. I'm running 1140 watts of panels and about 1000 Ah of AGM's which gives me 12 kWh (12v... yea, I know it was a mistake but it's history now). We currently use about 1.6 kWh daily, the fridge will add about another 1.2 kWh. So... 2.8 kWh daily. In a perfect world, I would like to keep my batteries at or above 70%, I can tolerate the odd day where it dips below 70% and I also have a pair of Iota chargers that add up to 85 amps (I know they don't charge at that) but I hate genny noise so I typically don't use the Iota's till I get down below 60% SOC. That only happens a couple of times a year when we get "a week" of overcast/snow/slush clouds in October. Based on some online research, we get about 6.5-7 hours of sun at peak and down to about 4-4.5 hours in October. So, enough rambling... do the numbers say I will have cold beer or is this cutting it too close? Thanks in advance for your advice, let me know if I should include some additional info.

# Posted: 21 Feb 2025 04:48pm - Edited by: gcrank1
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Best solar is 9-10am to 3pm, diminishing insolation on either side.
I liked mine on a normal day to recharge to full by noonish which gave me some overhead for use some extra use during the day while the solar was kicking. Late aft, evening and overnight was what I needed to catch up with next day, led lights were minimal but the small 120vac fridge was a bite on my 600w, 200ah system.
I think I would have been fine on your size. The energy efficiency of the fridge will be important. You need to check the mid to larger fridges, they may not take much more than a small one, but sizing to your need is important too. You dont want it too full or too much empty space either.

# Posted: 21 Feb 2025 05:09pm
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Thanks for that, we are moving to a 20 cu. ft. top freezer fridge. We bring enough food for 4-6 weeks. The fridge will not be energy efficient, I need something simple that I can repair myself (compressor excepted) so I've picked a very simple Frigidaire without boards or electronics. If a fridge breaks down where we are, it's 5+ hours of travel time plus repairs. The fridge becomes throw away sadly...

# Posted: 22 Feb 2025 07:04am
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Fridges are Basicly throw away items any way. $500-600 should get you a basic standard size new fridge.

I'm in central NY so lots of overcast days in spring and fall. I have 700w of solar and 8kwh of batteries. This is a weekend cabin so the whole place is shut down and batteries fully charged when I get back. We have no issues running a 4.3cuft fridge with top freezer. We do still have a 120v to 12v charger.

One thing I have noticed useing our fridge is durring the day i freeze 1/2gal jugs and over night i put them in the fridge. I really only do this when days have little solar input. I tried a timer having the fridge on for 15-30min every 2 hrs. That did nothing.

I think you will be fine with your setup...if not you will just run the generator a little more than normal. At the end of the day any power used from your solar is way more free than propane.

# Posted: 22 Feb 2025 08:25am - Edited by: FishHog
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I have a 12v fridge in the sudbury area. With 1400watts of solar. No issues in the summer, and no issues in the fall, as my fridge is not in the heated part of the cabin, so doesn't run much.
Not sure about a 120v fridge running off an inverter, but my unique 12v its not an issue. It is only 10ft3, but we stay for 3-4months at a time.

# Posted: 22 Feb 2025 08:31am
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I've been running propane fridges for 45 years and don't think I've ever had one blow out. Maybe you should look into that issue if that is your problem.

paulz
Member

# Posted: 22 Feb 2025 10:57am
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Quoting: FishHog

my fridge is not in the heated part of the cabin, so doesn't run much

Mine used to be near the wood stove until I moved it outside in the shade. Much better. I also have several of those freezer gel packs I bring when I come out. Good for a couple days but not a long stay, unless you could refreeze at the cabin during opportune times.

# Posted: 22 Feb 2025 04:05pm
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Nice thing about using your own water filled re-freeze jugs is you can always have some nice cold ice water available. We use those rectangular ones the cranberry juice and such comes in.
Freezers and fridges are most effective at holding the cold if the space is mostly filled with cold stuff, not mostly air.
We couldn't leave ours running when not there and it would take at least 1/2 day to start to get cold, really 24hrs. The best we found was to bring a chest full of our freezer jugs and frozen food to fill up the inside to kick start the process.
For us a big Yeti clone has worked great but we are off grid, low-power, 3 season part timers.

# Posted: 22 Feb 2025 04:10pm
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Hey FishHog, I'm in Canada, the fridge has to have an intake and outlet to outside or... no insurance. I've been back an forth with the company 30+ times, devised baffles, blocks and everything I could come up with to slow the wind in the past 13 years. The problem is that we are in the wide open after a forest fire, nothing to block wind but no different than being on a rocky windswept island. The company (Unique) unofficially acknowledges that it is a flaw in the design but they won't make the R&D effort to correct the problem because there are no a lot of us. The user manual has been change to read "locate the refrigerator in an ideal location away from the wind"...which is BS. The fridge must be located on a outside wall, I prefer my fridge in the kitchen. Not in a bedroom or hallway to get it "away from the wind". Yea... I'm frustrated. They went so far as to offer me a new unvented fridge but that would have to be located in a porch, garage or shed away from habitable areas. There would be a lineup up bruins waiting for lunch

# Posted: 22 Feb 2025 04:23pm
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OP here: A clarification, we live at our camp for 6 months. The fridge is on the entire time. The problem with blowing out arises when we go home for 3-4 days and we get a storm that blows out the fridge. If were there fridge goes out, I just relight it. Not a big deal. If it blows out on day 1 when were away and we get back on day 4 or 5... nasty and 2.5 hours to the nearest grocery store to restock. Very suburban Gogama BTW.

# Posted: 22 Feb 2025 05:27pm
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MY gut, without actual running an energy audit of your usage patterns tells me you will do fine with a fridge on your solar system.
Even so, the energy audit is always the first place to start.

# Posted: 23 Feb 2025 07:34am - Edited by: FishHog
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unfortunate your having fridge frustrations with Unique. Certainly a little more convenient to have the fridge in the kitchen, but we put ours just outside the heated area of the cabin, for efficiency reasons and both our electric and propane fridges sit there. Used to only have propane, but now the propane is just for backup when we have company.
Just takes us a little planning to think of what we need, go grab it all at once and put it all away at once. But I get that isn't ideal.

The problem with it being in a heated area is its going to run a lot more in the heating season which unfortunately is the same time that solar production goes to $hit, so your going to need a good buffer of solar and storage for that time of year which I don't think you have based on my experience a couple hours south of you, so will be even worse for your area.

So since you have a generator you could always try the electric while your there and see if your system keeps up. Put the propane one somewhere else for a backup for a while until you know you don't need it. Or use a smaller electric and keep your propane for backup if having company or an electrical issue.

If you find your running the generator too much (which like you is almost any running for me), add a couple more solar panels.

# Posted: 23 Feb 2025 02:57pm
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Thanks FishHog. Outside in a shed etc. is not really a starter for us, the bears are around till mid-October. They keep their distance but that's because were very careful with garbage, bird feed etc. They've torn doors off of camps in the area where people leave food out. HOW bad solar was in late fall was the first big surprise for me with solar way back when, half the capacity for my old FLA's and half the solar power reaching the panels. I just added another array and an Outback, problem solved. I may have to do that again. And your right, the fall is brutal for power production especially when your demands all go up. I've also noticed our falls seem to be a lot more overcast and just generally shite. The mile high blue sky's of October/November just don't seem to be there most of the time. I'm resigned to use the genny if I must, 1.5 litres of fuel brings me from 60-100% with the Iota's, great chargers. And I do plan to tuck the propane fridge away for a year till I'm "sure". Thanks again.

# Posted: 24 Feb 2025 11:04am
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I think with low light conditions and 1100w you may be a bit under paneled for your setup. Can your charge controllers take any more pannels? Have you messed around with series vs paralleling your pannels to see what gives you the most input on cloudy days?

Do you have a shunt meter?

I have a 12v30a iota charger I some times hook to my 1kw sportsman inverter generator. The 0.56gal tank give me 10-12hrs of run time. It was only a $200 generator too.

# Posted: 24 Feb 2025 11:44am
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Quoting: Brettny

I think with low light conditions and 1100w you may be a bit under paneled for your setup. Can your charge controllers take any more pannels? Have you messed around with series vs paralleling your pannels to see what gives you the most input on cloudy days?

I agree with Brett. I think you are going to be under panelled and super close to your limit. I like having excess solar so I'm not stressed and always watching my battery gauge.

I also think you may be a little high on the usage estimate. Well depending on the fridge you choose. We converted an upright freezer (7.0 Cu Ft) to be a fridge and it uses about 700Wh/Day running off our inverter. You can get that WAY lower if you convert a chest freezer. There are posts of people getting them as low as 200Wh/Day.

Of course there are trade-offs. The chest freezer sucks to use as you are basically pulling everything out to get 1 item (unless you devise some good organization scheme). The stand-up freezer is better, but you still need to manually defrost it... AND the shelves are too small to fit a 4L of milk in the upright position (we had to find an alternate container to pour our milk into).

If I were you, I would look at adding some more panels (maybe 600W, suggested as 300W panels are pretty darn cheap on Marketplace these days). Then look into converting a freezer or buying a convertible freezer (Costco stocks them).

P.S. We are in Northern Alberta, so a similar solar flux. We have 1950W of panels and about 11,000Wh of FLA batts. With that we can easily power our cabin with fridge and still run our mini-split for AC in the summer.

# Posted: 24 Feb 2025 12:37pm
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Hey Brettny, I do have a shunt meter. I didn't for 10 years and didn't realize how much I was missing. Regarding Iota, I also have a 30 and just picked up (cheap/new) a 55A. I checked and can run them together, just not consistently or one will wear out more quickly. I'm thinking they should charge at 50+ amps combined. I'll try that into the fall and see how it goes for 2025.

# Posted: 24 Feb 2025 12:53pm
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Quoting: travellerw

I also think you may be a little high on the usage estimate. Well depending on the fridge you choose.

The fridge is large(ish) at 20 cu. ft. but we need something that holds a lot (over a month) of food and frankly, a chest freezer does sound like a PIA to retrieve stuff. I remember that thinking back to my "yout". I do have some capacity for more panels but not much. I have one Outback FM 80 with 750 watts on it, I don't want to take it much higher because of those warming April days, The second FM 80 has 390 watts on it so a little room there. I would just have to figure out a way to insert a couple of panels into my "custom" mounting, image attached. Thanks for your insights.
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IMG_8384.JPG

# Posted: 24 Feb 2025 02:43pm
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Quoting: UpNorth48

The fridge is large(ish) at 20 cu. ft. but we need something that holds a lot (over a month) of food and frankly, a chest freezer does sound like a PIA to retrieve stuff.

That would explain your numbers. Ours is only a 8 cu. ft. Without more panels I really think you will be running your generator much more than you want.

Outbacks are great.. however if you don't have room you can always pick up a Victron for the new panels. Outbacks and Victrons play nice together. Victrons are affordable and reliable. Like I said, Outbacks are great but I think they are overpriced these days.

Adding a controller means you don't have to worry about voltages and mixing different panels.

# Posted: 24 Feb 2025 02:49pm - Edited by: travellerw
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My initial thoughts.

Move the closest wood pile.

Sink 2 galvanized fence posts into the ground (auger and cement).

Use a galvanized pole between the 2. (horizontal)

Attach the new panels from that pole up to the old panels. (Cheap and VERY secure).

I have attached a VERY crude drawing to make it a little clearer. Of course the angles aren't right as I'm a terrible artist.

Untitled.jpg

# Posted: 24 Feb 2025 05:34pm
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You have two outback charge controllers and only 1100w on them? Add more pannels. You will prob never see full output of those pannels so adding more shouldnt hurt anything. What's the manufacturer spec on max wattage input?

A lean too wood shed with solar on the roof would be a nice addition and double duty.

I have 705w on a 40a epever BN series.

MtnDon
Member

# Posted: 24 Feb 2025 06:04pm - Edited by: MtnDon
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Quoting: Brettny

You have two outback charge controllers and only 1100w on them? Add more pannels

According to Outback a 12 volt system limits the panel wattage to a max of..... "Maximum PV array power: 12VDC systems: 1000 Watts;". The 12 volt battery system is hampering any attempts to increase panel watts. Then with the FM80 that does have some room to increase panel watts it can be difficult to find panels with close volt & amp matches. A third array with a new controller would also provide the option of aiming in a slightly different direction to get more output earlier or later in the day.

As for using a Victron controller with the FM80's, that works but if the OP is using the Outback Mate system that would be a stumbling block.

# Posted: 24 Feb 2025 06:55pm
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MtnDon, wow its been a while. Welcome back.

# Posted: 24 Feb 2025 08:49pm
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Quoting: MtnDon

A third array with a new controller would also provide the option of aiming in a slightly different direction to get more output earlier or later in the day.

Thanks for the suggestions MtnDon. I think I can lay my hands on two more of those BP 195w panels... so a little less than 800w on the second Outback. I agree, the Outbacks are $ but they were a reliable option back in 2012 when I did this, not a hiccup in 12 years (I really hate to say things like that "out loud"). I like your idea of another array with a slightly different orientation. These are set at 26D west of south to maximize solar noon in the fall, a new array could be oriented due south. I'll run with what I have for this year with an eye on performance and look at improvement, if required, 2026. Thanks again.

# Posted: 24 Feb 2025 09:37pm
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I like the idea of maxing out the input to the SCC's you have then a new array oriented for more day capture.

# Posted: 25 Feb 2025 07:28am
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why buy 195w panels when the 300-350w are not much bigger and are relatively cheap these days. You will never regret more solar.

MtnDon
Member

# Posted: 25 Feb 2025 09:10am
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Quoting: FishHog

why buy 195w panels

When adding to an existing array the Vmp and Imp ratings of the old and new panels should be within 10%. When panels are mismatched the panel with the lower value restricts the output of the higher rated panels . That's the simplified answer.

# Posted: 25 Feb 2025 10:53am
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Quoting: MtnDon

Exactly why I suggested a new string. You will get more solar and it will probably be cheaper (even with the cost of a Victron controller). You also get redundancy in the event of a controller failure.

Of course there are multiple ways to skin a cat so to speak. However, I think trying to max out an old existing controller just to get some extra "value" out of it is a fools game these days. High quality, fast MPPT controllers are super affordable and reliable these days. Buy the best value panels and keep like panels on their own string. IMHO.

# Posted: 25 Feb 2025 11:11am
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Well to be fair a 80a victeon controller is about $400 plus panels. Adding more pannels to current controllers would typicaly cost 20-40c per watt. Well less than just the controler.. not including wire and breaker needed.

# Posted: 25 Feb 2025 12:22pm
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That was definitely an oversight on my part. The whole 12V thing.

However, even at 12V a 150/45 can have 650W of panels connected. A Victron 150/45 can be bought for $200 USD if you wait for a sale.

Depending on how things are wired, the wire would be a wash between a new string and adding to an old. I personally don't do breakers on the solar side as if you spec the wire properly it can take full short circuit current without problems. A disconnect switch I do include though.

Even at 12V, I think a new string would be the path I would choose.