diy solar

diy solar

I need help.

The OP didn't say where in Alaska, so someone started with Fairbanks, I continued. I just ran numbers through PV Watts, and switched to a more optimistic Anchorage per Maast. I did 2 examples, one at no tilt on the roof, one at 90 degree, magically mounted on the wall. The results are monthly. 90 degrees gets you 33kWh a month in Dec, so basically 1kWh a day. His heater uses 400Wh, so that's fantastic news. But, his panels are on the roof, at 0 tilt, he gets 4kWh a month. That's 133Wh a day. Brrrrr.

PVWatts Calculator 90.pngPVWatts Calculator flat.png
 
For giggles, I put it into PVWatts (900W, flat with 16% inefficiency):

The total solar harvest from Nov to Feb is 26kWh - enough to charge the battery about 5.5 times (or 4 hours of heater running per night average, nothing more):

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Assuming panels mounted on the side facing South, that same period could charge the battery 23.5 times (18.8 hours of heater running per day average):

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What about stowable flex panels you can hang from the side of the van with magnetic hooks?
 
For giggles, I put it into PVWatts (900W, flat with 16% inefficiency):
No way on earth an off-grid system will get 16% efficiency. I was being generous when I did 30%. But we did come up with almost identical results. Ironically at almost the exact same time. People are going to start talking about us Snoobster. Ever notice we've never been seen in the same room at the same time? Just sayin....
 
No way on earth an off-grid system will get 16% efficiency. I was being generous when I did 30%. But we did come up with almost identical results. Ironically at almost the exact same time. People are going to start talking about us Snoobster. Ever notice we've never been seen in the same room at the same time? Just sayin....
Ha ha. Solar Queen and Snerbler threads have become must-reads for me. :)
 
No way on earth an off-grid system will get 16% efficiency. I was being generous when I did 30%. But we did come up with almost identical results. Ironically at almost the exact same time. People are going to start talking about us Snoobster. Ever notice we've never been seen in the same room at the same time? Just sayin....

I can dream! I figured it wasn't outrageous since his main load is DC and he's using LFP... But this is one of those cases where you're MORE right... :)

For me it was eye opening to see how that equates to the # of charges over 4 MONTHS.

Loved my week in Fairbanks, but damn... I felt like I needed an afternoon nap all day.

The northern lights were amaze balls.... Whole purpose of the trip. Bucket list stuff. Bonus was being able to see Denali from our Airbnb window 140 miles away on the clearest day.
 
I am in Anchorage but I can be sent to barrow for up to six months. The van will stay in Anchorage when I am out of town but when I am in town I want my stuff to work. I just didnt think my system is working properly. And I will need to install a shunt and a renogy dc to dc charge controller I guess.maybe I should build another van or trailer with a stove in it.
 
Loved my week in Fairbanks, but damn... I felt like I needed an afternoon nap all day.

The northern lights were amaze balls.... Whole purpose of the trip. Bucket list stuff. Bonus was being able to see Denali from our Airbnb window 140 miles away on the clearest day.
Nice! I've been twice, but in summer, so never saw the northern lights, still on my list. Maybe in Iceland, shorter flight for me. If we can ever travel again.

Probably TMI, but, hey, we're all family here, here I am (in my 20's) at the Kenai Fjords. We were dry camping for 3 days after catching a ride on a fishing boat, who let us fish. We caught 8 salmon and had no ice. So being from New England, it was decided I would swim way out to the nearest iceberg, tie a rope around it, climb on, and get towed in. Mission accomplished, and got what is probably one of my favorite pictures of all time (you can see the rope as they pulled me in).
amy iceberg.jpg
 
I am in Anchorage but I can be sent to barrow for up to six months. The van will stay in Anchorage when I am out of town but when I am in town I want my stuff to work. I just didnt think my system is working properly. And I will need to install a shunt and a renogy dc to dc charge controller I guess.maybe I should build another van or trailer with a stove in it.

Well, while you're away, it should get fully charged! Maybe a portable stove is a better solution than building a van around a stove? :)

Nice! I've been twice, but in summer, so never saw the northern lights, still on my list. Maybe in Iceland, shorter flight for me. If we can ever travel again.

Probably TMI, but, hey, we're all family here, here I am (in my 20's) at the Kenai Fjords. We were dry camping for 3 days after catching a ride on a fishing boat, who let us fish. We caught 8 salmon and had no ice. So being from New England, it was decided I would swim way out to the nearest iceberg, tie a rope around it, climb on, and get towed in. Mission accomplished, and got what is probably one of my favorite pictures of all time (you can see the rope as they pulled me in).

ZERO surprise you'd brave the swim in the frigid waters. I am surprised you're not just riding it like a giant wakeboard while holding the rope.
 
I am in Anchorage but I can be sent to barrow for up to six months. The van will stay in Anchorage when I am out of town but when I am in town I want my stuff to work. I just didnt think my system is working properly. And I will need to install a shunt and a renogy dc to dc charge controller I guess.maybe I should build another van or trailer with a stove in it.

I think you need a carbon-neutral solution to heat. Whale oil? 1601096368712.png
 
Well after some cloudy days today is the sunniest day I have had in a while. I checked my battery again and these are my results from this morning. (I will
You're screwed :LOL:

Yeah I know.

With the soc chart that was provided it seems that one big battery isn't the way to go. Should I separate the cells into two 200ah batteries? Instead of one big 400ah battery. It seems that the battery drains pretty quickly from ~13.4v to 12.8v's I would just need to get another set of bms's.
 

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Well I checked again on my lunch and it seems that that's all I get today. I think the sun went away for a while. The first photos I took around 11:50 am this was at 6:10 pm.

I think maybe I need to divide my battery.

Also how much would it effect my charging off the solar charger positive lead is not directly on the terminal. It's a few connections deep but still on the terminal.
 

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PowermaxPM3-12LV AC-DC 45A converter for charging from 110VAC shore power or generator (if you just want it for shore power, they go up to 100A, but anything larger than 45A will overload that small generator)
Are there any tutorials to make sure the charging parameters are compatible with lifepov4?
 
Well I checked again on my lunch and it seems that that's all I get today. I think the sun went away for a while. The first photos I took around 11:50 am this was at 6:10 pm.

I think maybe I need to divide my battery.

Also how much would it effect my charging off the solar charger positive lead is not directly on the terminal. It's a few connections deep but still on the terminal.

You have 12V, 400 Ah, 5 kWh.
Charge controller showed 1.14 kWh for the day.
If no loads, in 4 or 5 days battery should be charged, unless voltage is insufficient; in which case you'll see kWh for the day taper off.
Or unless you keep draining it. What loads does it power each day/night?

If you drive often, instead of trying to charge the battery and use battery to power an electric heater, how about sleeping with a water bottle? A big water bottle ... just need some way to heat it from the engine. Coolant is pressurized typically up to 15 PSI. If you ran a tube through a copper line inside a giant, insulated water bottle ... have to keep it from getting hot enough to blow up as a steam balloon. Ok, get a 6 or 10 gallon electric water heater. Clearly label it "Non-Potable". Plumb your cooling system through it. You now have a tank of heat to somehow circulate though tubes under your bed.
 
Are there any tutorials to make sure the charging parameters are compatible with lifepov4?

With nothing connected, you turn a pot to set the absorption voltage where you want it. Once set, you attach it to the battery and charge when needed. It will follow a 3 cycle charge profile (bulk, absorp, float - good for both lead and LFP). I'd set it to 14.2. If the BMS trips, knock it down 0.1V until it stops tripping.
 
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