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colsankey
02-12-2022, 04:20 PM
My family has a water access only cabin in BC. No electricity or gas, water comes from a creek.

Brother wants to do some remote work and dad wants to be able to charge cellphones, etc for emergencies.

Ive really got no idea aside from the black box components of a solar install we would need.

I assume we need some panels - how many watts would be enough for a 200w laptop and a couple phones charging?

Inverter - something to turn the dc to ac ?

Controller? Do you need anything charge a battery or 2 and provide some ac outlets or will an inverter do this?

Battery - 1 or 2 batteries, load isnt high but would want a bit of a power reserve for cloudy or stormy days. Cabin is on a fresh water lake so corrosion is there, but not the same as on the coast with salt water.

If anyone with some experience has some suggestions on parts id need or basoc designs, id love to see em.

tirebob
02-12-2022, 04:56 PM
One of my best friends actually has on off-grid cabin in BC and easily help walk you through the kinds of things you will need and gets people really solid deals on the equipment too. He is a legit good guy and if you name drop me I am sure he will go the extra mile for you...

https://domssolardistribut.wixsite.com/domssolardistributio

It is a small biz for him outside of his 9 to 5 job so he may need to get back to you but I have not heard anybody say it wasn't worth it for them to deal with him.

ExtraSlow
02-12-2022, 05:16 PM
It's not wildly complex, but you either have to really enjoy the nitpicky details, or work with a professional for design. Actually at least a handful of solar companies in town that would love to help you with this.

Its basically the same use-case as RV solar. There's a couple guys on here who have done that.

Also, if it was me, I'd oversize the loads you are planning for. And I'd have a Honda 1000eu.....

jwslam
02-13-2022, 02:32 AM
Jackery?

ZenOps
02-13-2022, 07:03 AM
Assuming you want to try yourself (Less than 40 volts to ensure not as dangerous)

Overpanel. For BC, get panels that produce some energy on cloudy days. Monocrystalline for sure, probably two or three big LG panels?

https://www.lg.com/us/business/solar/neon-2-series-solar-panels

https://www.youtube.com/c/HOBOTECH

Jackery is good, if you want more Bluetti. All-in ones are a lot easier to setup (and probably safer) than ones with seperate batteries. You must match the number of panels, and voltage, and amperage to the maximum capability of the battery and circuitry of whatever you are using.

It might be worth going low end to start, just to get the basics down to make sure its even doable. Golabs for USB charging (be careful to get a pure sine wave if using AC) with a cheap or used 100 watt 12 volt panel to practice on. You then get an idea of how devastating it is when you put one hand over any part of panel.

B.Spilner
02-13-2022, 02:13 PM
Jackery?

That's what I was thinking. $2k on Amazon gets you a good portable bundle, more then enough for OPs needs.

And there's always Amazon coupons for $2-300 off.

suntan
02-13-2022, 02:42 PM
Don't get the Jackery solar panels, they're not wet rated at all.

cyra1ax
02-13-2022, 03:54 PM
Fine, Ecoflow Delta then.

Yolobimmer
02-13-2022, 04:33 PM
There's a beyond member on Facebook that sells solar equipment. I don't know his name here, but if you search solar panels on FB marketplace, his name is Rasmus.

Seems to know his stuff.

pheoxs
02-13-2022, 04:44 PM
For that small of use you're basically looking for what the van-life people use. Full home solar setups will be in the ~6kW range whereas yours you'd probably be fine with 400-800W setup.

Renogy is very popular for solar stuff and quite reliable. It's a bit more pricey than some of the cheaper brands but it's also still widely recommended for reliability and safety.

400W setup would probably be plenty for what you need. They also have a 800W kit for 400$ that might be worth going just for the sake of future-proofing. Note that you can use more than 400W through the inverter just fine, it might just mean your batteries drain so on partial sun days a bigger setup will get you more power. If it's cloudy for quite a few days in a row 400W might have a hard time retopping up the batteries.

Renogy 400W kit (https://www.renogy.com/new-400-watt-12-volt-solar-premium-kit/)
Renogy 800W kit (https://www.renogy.com/new-800-watt-24-volt-solar-premium-kit/)

Then you'd need a inverter. It's important to get a pure since wave one since you'll be running computer / important electronics off it. Note that 3kW means you can run a lot off it for short periods, like if a lady is over and she wants to use a hair dryer that's perfectly fine. The batteries can handle that short term load no issue.
3000W Pure Sine Wave Inverter (https://www.renogy.com/3000w-12v-pure-sine-wave-inverter-charger-w-lcd-display/)

Then you want batteries, if its just a laptop and phones then you'd probably be good with 200Ah of LiFePo4 batteries (equivalent to 400Ah of AGM batteries). I've seen a few adds for these guys, they seem local and have been around for a few years. They just resell cheap chinese batteries but they seem to still be busy enough that I'd assume they chose a good supplier. The batteries are easy because you can just add more at any time without swapping any other hardware (there's a procedure for adding a second battery you need to follow to get them to the right charge)
280 ah LiFePo4 battery (https://www.ablithium.ca/products#!/280-ah-deep-cycle-pre-order-Feb-Shipment/p/322700074/category=94002008)

That'd basically be it. Those 3 items and some wire, and probably a disconnect switch / fuses and you'd be set. This is on the bit more pricey / buy it for the long term recommendations. If you want to go cheaper you can grab a cheaper pure sine inverter from Canadian tire for a couple hundred bucks, and fine a few hundred W solar panel kit as well. But this at least is a parts list for what you need.

colsankey
02-17-2022, 04:15 PM
I've reached out to Bob's guy, but its been 20 years since I did any real power calculations.

My usage case changed, old people want lights in the evening to reduce propane reliance, 6pm to midnight is pretty typical for lights, will add 2 hours for late nights or people needing it in an emergency.

If I assume 8 hours usage for all devices, my estimated load off 120v AC is: 140W / hour
lights 20W
laptop 80W
2x cellphones 36W

So 136W x 8H = 1,088 Watts / day

Back of napkin math says a 12V 120AH battery is 1440W, so I should get a days usage out of a single battery, assuming it's lithium or similar and not lead-acid where I'll see a voltage drop after 50% usage?

Also, assuming there's family over 2-3 weeks in a row and the panels don't get a few days to charge, I need enough panels to restore the full load of the battery daily, so I'm looking at needing 1200-1400W of panel capacity?

Does that make sense, or am I way off here?

ExtraSlow
02-17-2022, 04:41 PM
I think you will find that once you have power, you'll use more power than you expect. Like a hell of a lot more.

colsankey
02-17-2022, 05:15 PM
Perhaps. But its a shared family cabin amd some of the family fought tooth and nail against any power at all, so this is the happy medium, in theory.

If i had my way thered be a tesla power wall, generator and 10,000 watts on the roof in BC and at home.

killramos
02-17-2022, 05:21 PM
If that’s the case I’d setup my own gen and lot let those luddites use it

vengie
02-17-2022, 05:38 PM
If you guys need solar panels let me know.
I might know a guy.. wink wink, nudge nudge

ExtraSlow
02-17-2022, 05:44 PM
colsankey, if that's the case, set it up the way your planned, maybe have more battery capacity or something, and you can always bring your own 1000w gas genny if you feel like it. Handy if you happen to be there when it rains for a few days, or it's cold and dark, or whatever.

- - - Updated - - -


If you guys need solar panels let me know.
I might know a guy.. wink wink, nudge nudge

This guy knows things.

pheoxs
02-17-2022, 10:33 PM
Don’t forget the loss of the inverter. Just being on it consumes power too.

How sunny is this cabin in BC and how much shade from trees? That really affects things. Lots of Van people run 200W panels with 100ah battery or 400w with 200-300ah batteries. That typically is a nice balance of recharging it through the day while having capacity to last a day or two if it’s cloudy out.

1200W would provide your full days usage in a single hour (assuming bright sun) so you really don’t need that much unless you expect it to be lots of overcast days so it’s rare the panels high peak production.

For Calgary you can expect 1kW of Solar to produce 1000-1200kWh across the entire year. Or 3-3.5kWh (3,500Wh) per day averaged across the year. In reality summer will be the bulk of that. So closer to 8-10kWh on a sunny day. Give or take. BC obviously is less sunny.

If this is a weekend cabin I’d focus more on batteries than solar panels. Because they’ll charge all week while you’re gone and then you can use what you want while you’re there. Same goes for a few weeks. More battery power will help average out less sunny days.

Note if you’re going through this, I’d say consider swapping the lights for 12v led lights. And some dc-dc USB ports. Then you can run most things without the inverter and then turn it on for when you need to charge a laptop or use an appliance. Also definitely budget for more power, once you have power then you’ll want stuff like a cofffee maker or mini fridge.

ExtraSlow
02-18-2022, 08:20 AM
pheoxs is right on. DC LED lighting, focus on batteries, inverters cost power.

And if you find yourself running out, a small genny is an easy addition.

ZenOps
02-18-2022, 09:54 AM
A bigger battery is nice, even when bundled with a carbon generator. Reason being: Two or three cloudy days in a row and any size battery will be empty. If you can simply charge up the battery for a few hours burning some gasoline, the rest of the time you can have all the benefits of being completely silent while also having redundant power.

It also means you can use a cheap carbon generator (loud), because you can control when its running.

Me personally: I'd consider just straight up more solar panels than needed, especially when the QD solar panels start showing up. Solar generate far more than you need most days, and simply bleed off the excess through a few sets of 100 watt infrared only reptile bulbs or something similar.

https://www.amazon.ca/Simple-Deluxe-Infrared-Amphibian-Incubating/dp/B07KLZCDQH/

https://www.amazon.ca/DEWENWILS-Countdown-Polarized-Function-Christmas/dp/B08FYFQ698/

Or

https://www.amazon.ca/Fosmon-Electrical-Countdown-Photocell-Weatherproof/dp/B07GX3TQ93/

https://www.amazon.ca/Delonghi-TRH0715CA-Portable-Oil-Filled-Radiator/dp/B000FT1XZW/

Anything over 1,000 watts excess though, and its probably overpanelled.

If its a sunny day at 10AM, and you know that you will be overgenerating for the afternoon, just press the four hour button for some extra ambient heat (more useful for Calgary)

The main quibble I have with Jackery is that they have not moved to Lithium Iron Phosphate batteries yet. LiFePO4 has at least 4x overall longevity in cycles, and it can survive down to -30 Celsius when not in use or discharging. Regular lithium ion should be kept above zero celsius at all times.

IF you are looking to run for a decade, LiFePO4 on paper will need to be replaced far less often. A lead acid will do about 200 half cycles if you get the wrong one, a good LiFePO4 should do 2,000 full cycles (to 80%). LiFePO4 is usually quoted for ten years (to 80%)

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