diy solar

diy solar

On Keeping LFP Warm

Nice!! How do you seal the edges where panels meet?
Personally using adhesive backed closed cell neoprene sheets, 1/8 inch or 1/4 inch.
I cover all six (6) faces of the panel before putting the panel into the assembly further.
Gentle compression from structure keeps neoprene in place.

This kind of neoprene, but wider sheets: 1628886424314.png

Naturally, one layer of 1/4 inch neoprene on each side of a 1 inch panel will of course turn it into a 1.5 inch panel.

Have used this: Sponge Neoprene With Adhesive 1/4" Thick X 54" Wide X 1' and it works well enough for me.

Panasonic recommends adding padding to it to reduce thermal bridging also. The fiberglass core is relatively conductive and padding with neoprene helps optimize the thermal characteristics too :)

1628886940038.png

For more info please refer to:
U-VacuaTM Vacuum Insulation Panels - Handling Guidelines
 
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Personally using adhesive backed closed cell neoprene sheets, 1/8 inch or 1/4 inch.
I cover all six (6) faces of the panel before putting the panel into the assembly further.
Gentle compression from structure keeps neoprene in place.

This kind of neoprene, but wider sheets: View attachment 60001

Naturally, one layer of 1/4 inch neoprene on each side of a 1 inch panel will of course turn it into a 1.5 inch panel.

Have used this: Sponge Neoprene With Adhesive 1/4" Thick X 54" Wide X 1' and it works well enough for me.

Panasonic recommends adding padding to it to reduce thermal bridging also. The fiberglass core is relatively conductive and padding with neoprene helps optimize the thermal characteristics too :)

View attachment 60003

For more info please refer to:
U-VacuaTM Vacuum Insulation Panels - Handling Guidelines
Dang.... now I am going to have to buy some of those for my next project!!!! I'll send you the bill!!! :ROFLMAO:
 
I wouldn't worry too much about the cold temps and regular electronics, assuming you are talking about solar power components. We leave our inverter in standby and the SCC on as usual all winter.
Unfortunately that IS my biggest worry, at least for now. Almost all the All-in-one charger/inverters I’m considering have modest cold operating temp specs (e.g., Midnight Solar’s MN3024DIY is 5F and the MPP Solar units that Will Prowse likes indicate just 32F…). The problem is I assume my “typical” outside temp can get to -40F at least every other winter or so. Neither my basement floor nor my roof is insulated and until I wire and chink my cabin, I still have actual air gaps between logs (some large) to the outside, and to add insult to injury, unlike yours, all 6 of my windows face every direction but south. I expect to use the cabin just a few cold overnights each winter (snowmobile access only), but just want the peace of mind to know that charging system keeps working…. I hope to have my monitoring system on a separate low power DC circuit so my inverter can be shut or in sleep mode. So whenever someone like you has info on basement temps in cold environs, I get excited…. Cheers.

Link to my original cabin post and pic of the cabin itself:
1628887032272.jpeg
 
Cold Climate Housing Research Center published this report about vacuum insulated panels: http://cchrc.org/media/VIPs_Report.pdf
They tested these things in real building panel assemblies in Alaska to get real world data ?❄️

Here's some goodies:
Conclusions
Overall the product works well with a variety of adhesives. The largest challenge is the fragility of the material. Any encounter with a sharp object can puncture the Mylar coating which causes the panel to lose thermal performance. Careful construction practices and/or more robust packaging can mitigate this problem. CCHRC recommends evaluation and testing of potential manufacturing process that incorporate the VIPs into a larger package like a SIP that would protect the VIPS in wall applications.
Getting the VIPs from the packaging to the wall is still a delicate process and at this point the best suggestion is to keep them packaged until the last minute. Do a sweep of the area of extraneous sharp points before removing them from their packaging. And take them from the package and stick them directly to the wall. A spray adhesive or double sided tape that adhere immediately are the best options to hold the VIPs in place and away from potential sharp points. Packaging the VIPs in a more protective manner, like encasing them in 1⁄4 inch (6 mm) EPS would improve durability greatly.
 
Unfortunately that IS my biggest worry, at least for now. Almost all the All-in-one charger/inverters I’m considering have modest cold operating temp specs (e.g., Midnight Solar’s MN3024DIY is 5F and the MPP Solar units that Will Prowse likes indicate just 32F…). The problem is I assume my “typical” outside temp can get to -40F at least every other winter or so. Neither my basement floor nor my roof is insulated and until I wire and chink my cabin, I still have actual air gaps between logs (some large) to the outside, and to add insult to injury, unlike yours, all 6 of my windows face every direction but south. I expect to use the cabin just a few cold overnights each winter (snowmobile access only), but just want the peace of mind to know that charging system keeps working…. I hope to have my monitoring system on a separate low power DC circuit so my inverter can be shut or in sleep mode. So whenever someone like you has info on basement temps in cold environs, I get excited…. Cheers.

Link to my original cabin post and pic of the cabin itself:
View attachment 60004
Wow. Nice insulation. :oops:
 
My Next test will be to throw a folded towel over the thermometer to try to measure the actual slab temperature a little closer. My expectation is that it will rarely get much above 70 or 71F, if ever.
I threw the towel over the thermometer about 24 hours ago. The temp dropped to 73.4 and has stayed there since. Therefor I conclude the concrete slab is around 73F. I'll let it go and see what it does on really hot days. (Today looks like it is going to be pretty hot)
 
I just finished my shop battery. In my half insulated "I'll finish it one day I promise" shop I have built a 375ah 48v 16s15p topband 25ah cell battery. I assembled it in 3 layers in a small deep freeze. I wired the bms in with the battery and put a 20watt propagation mat between battery layer 2&3 hooked to a temp controller.

I then replaced the flimsy plastic sheet on the underside of the lid with a rigid sheet of luan, and attached a greenhouse wax motor vent to the inside of the deep freeze. I also removed the hold open springs from the hinges, so that I don't risk the lid not closing when the shop gets cold. I set the temp controller to 50F.

where I'm at, the temp at night can drop under -40f in the middle of winter. I use power daily, whether I'm home or not, so the waste heat from the bms's will always be radiating into the box, this is why I included the wax motor, I am just as concerned w/overheating as freezing. the bms should cut off charging before there is a problem(currently set at 2c) so heating pad should kick in at 50F off at 52F vent should open starting at about 75f. I'll try to remember to keep you all updated on how it's performing.
 
Unfortunately that IS my biggest worry, at least for now. Almost all the All-in-one charger/inverters I’m considering have modest cold operating temp specs (e.g., Midnight Solar’s MN3024DIY is 5F and the MPP Solar units that Will Prowse likes indicate just 32F…). The problem is I assume my “typical” outside temp can get to -40F at least every other winter or so. Neither my basement floor nor my roof is insulated and until I wire and chink my cabin, I still have actual air gaps between logs (some large) to the outside, and to add insult to injury, unlike yours, all 6 of my windows face every direction but south. I expect to use the cabin just a few cold overnights each winter (snowmobile access only), but just want the peace of mind to know that charging system keeps working…. I hope to have my monitoring system on a separate low power DC circuit so my inverter can be shut or in sleep mode. So whenever someone like you has info on basement temps in cold environs, I get excited…. Cheers.

Link to my original cabin post and pic of the cabin itself:
View attachment 60004
just saw the part of this post about mppsolar and cold temp. So I didn't notice these specs before installing mine, 2 years age in an unheated shop that's probably not to far from you (SLV) I've got 3mg5048's stacked into 415v3p and an lv5048 for 120v power while I don't recommend the lv5048 (clunky design 2 inverters stuffed into 1 box) I've never had a cold weather problem with them.
 
just saw the part of this post about mppsolar and cold temp. So I didn't notice these specs before installing mine, 2 years age in an unheated shop that's probably not to far from you (SLV) I've got 3mg5048's stacked into 415v3p and an lv5048 for 120v power while I don't recommend the lv5048 (clunky design 2 inverters stuffed into 1 box) I've never had a cold weather problem with them.
Thanks wild01. SLV? SLC (salt lake)? If so, I think we get quite a bit colder, almost 5 hours north of you. That said, you definetly get far below the MPP temp spec, so your note is comforting….. ?
 
Thanks wild01. SLV? SLC (salt lake)? If so, I think we get quite a bit colder, almost 5 hours north of you. That said, you definetly get far below the MPP temp spec, so your note is comforting….. ?
no san luis valley sorry I mixed you up with another poster from Colorado. the san luis valley is in southern colorado, but is also one of the coldest spots in the continental us. we are a 7-8000ft valley the size of Connecticut in southern Colorado. high desert almost every winter we achieve coldest spot in the nation several times. The only place I've ever lived where my septic has frozen solid. -30f is a give every winter -46 is the coldest I've seen at my house. the year my septic froze we where the coldest spot in the nation for 56 days in a row. other claims to fame are 80mph sustained spring winds.
 
almost every winter we achieve coldest spot in the nation several times. The only place I've ever lived where my septic has frozen solid. -30f is a give every winter -46 is the coldest I've seen at my house. the year my septic froze we where the coldest spot in the nation for 56 days in a row. other claims to fame are 80mph sustained spring winds.
....and you live there why??
 
What if you built your battery into a large fibreglass ice box and submerged them in non-electrically conductive mineral oil (like an oil PC) and added an aquarium heater.
 
What if you built your battery into a large fibreglass ice box and submerged them in non-electrically conductive mineral oil (like an oil PC) and added an aquarium heater.
then you will hate yourself with a passion the first time you have to disassemble the whole pack to fix a minor wiring error. there will be much cussing and heavy oily slick battery cells...but it would probably work... did I mention the cussing
 
no san luis valley sorry I mixed you up with another poster from Colorado. the san luis valley is in southern colorado, but is also one of the coldest spots in the continental us. we are a 7-8000ft valley the size of Connecticut in southern Colorado. high desert almost every winter we achieve coldest spot in the nation several times. The only place I've ever lived where my septic has frozen solid. -30f is a give every winter -46 is the coldest I've seen at my house. the year my septic froze we where the coldest spot in the nation for 56 days in a row. other claims to fame are 80mph sustained spring winds.
Thanks wild01, now SLV makes sense….. I know the area a little, lived in Gunnison as a baby, went to college in NM in the 80s, and worked near Denver in the 90s. Your SLV has very similar winter COLD conditions to Island Park, Idaho, which is approx 6300ft and next to Yellowstone NP. It’s GREAT to know that your electronics can work / survive in an unheated shop. This temp thing has got me on edge, but now just a little less so.…? Cheers.
 
Thanks wild01, now SLV makes sense….. I know the area a little, lived in Gunnison as a baby, went to college in NM in the 80s, and worked near Denver in the 90s. Your SLV has very similar winter COLD conditions to Island Park, Idaho, which is approx 6300ft and next to Yellowstone NP. It’s GREAT to know that your electronics can work / survive in an unheated shop. This temp thing has got me on edge, but now just a little less so.…? Cheers.
Yeah, i think the main thing these
inverters have going for them in cold is they aren't the most efficient. which=self heating. Also about the only thing I've ever had cold weather problems with in electronics are motors...fans/harddrives i think it's a grease problem in their bearings ...In an inverter if it's cold it shouldn't be trying to run the fans.

Anyway mppsolar doesn't have the greatest design, but they work ok as long as you don't push them. I have killed a few, if you get one don't try to run a heavy load 'through' one with a generator. Wire your system so that if you are gen charging your other ac loads are powered directly off the generator. Most inverters have a built in bypass, as far as I can see these DO NOT. So if you are using power to charge the batteries and run loads at the same time bad things can happen if something tries to pull to much power.
 
Yeah, i think the main thing these
inverters have going for them in cold is they aren't the most efficient. which=self heating. Also about the only thing I've ever had cold weather problems with in electronics are motors...fans/harddrives i think it's a grease problem in their bearings ...In an inverter if it's cold it shouldn't be trying to run the fans.

Anyway mppsolar doesn't have the greatest design, but they work ok as long as you don't push them. I have killed a few, if you get one don't try to run a heavy load 'through' one with a generator. Wire your system so that if you are gen charging your other ac loads are powered directly off the generator. Most inverters have a built in bypass, as far as I can see these DO NOT. So if you are using power to charge the batteries and run loads at the same time bad things can happen if something tries to pull to much power.
Thanks wild01, I hope to never use my small generator (Honda eu2200i) to power my batteries, just PV for them babies), at least that’s the plan.
 
OK so nighttime temps have dropped in the last week to 16 centigrade at night. it has not gotten cold enough in my power plant (solar shed) to activate the heater plate system I built. but I did take the precaution of wiring the solar controllers not to charge unless its above 14 Celsius. I will have to watch the system when I am there on the weekends to determine if it is working properly or not. still efforting using a wifi hotspot/cell phone linkup to tie into my magnum inverter and morningstar SCC's so that I can remotely monitor the batteries. until then I have to use the failsafe of not charging below 14°C. To date the lithiums have totally blown me away. the last month has been up to a week at a time at 45%-65% charge and no issues they run the fridge freezer, septic pump 24-7 and the A/C on timer from 1000-1400 dailey. thats with heavy overcast each day. for whatever reason the magnum shows a high voltage fault every day of 70+ volts. I think it is the disconnect of the solar controllers when they hit max charge. the BMS has never shut down, and I know this as without the inverter powering the house the A/C would drop its memory settings (which it has not.) So I am guessing a spike when the last of the 4 solar controllers shuts off charging. I can think of nothing else. it happens at a different time each day. but without the tie in to the solar controllers its a guessing game at the moment.

there are some things to be said for the all in one, or the fully integrated systems like victron.

R

Ken
 
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