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370 Watt Solar Panels $225 each

Posted: March 16th, 2024, 8:43 pm
by Fred
Length 69.9in
Width 41.2in
Rated Power Output 370 W
Voltage (VOC) 41 V
Maximum String Voltage 1000V
Number of cells 120
Cell Type Monocrystalline
Rated Efficiency 19.88 %
Connector Type MC4-compatible
Backsheet Color black
Frame Color black
Dimensions LxWxH 69.9 × 41.2 × 1.3 in
Weight 43 lb,

While supply lasts. I currently have 92 left. Located in Duchesne, Utah

Re: 370 Watt Solar Panels $225 each

Posted: October 1st, 2024, 12:49 pm
by mudflap
Hi Fred -
Not sure the best place to post this, but what are your thoughts on Nickel Iron Batteries / Edison batteries?

It seems to me, that if a person:
- is environmentally conscious,
- is interested in stupid simple ideas
- wants to be as independent as possible
- is prepping for a major SHTF or societal collapse event

.....that even though solar panels would be something you couldn't get, that at least you would avoid Lithium Ion batteries, which would be nearly impossible for even the most robust DIY'er to make.

OTOH....
nickel iron batteries could be made with simple off-the-shelf items such as
- a plastic barrel
- iron plates
- nickel plates
- insulating plates like a perf board or something - silicone, maybe?
- some insulated wiring
- solder
- a few bolts and nuts
- some potassium hydroxide (drano)

----
and the reason they aren't popular is because nobody can make money off them, since they last 50 years....

what am I missing here?

https://youtu.be/K84PywMwjZg?si=Y6Cxq9IKL_XQe909&t=51

Re: 370 Watt Solar Panels $225 each

Posted: October 1st, 2024, 12:55 pm
by creator
Fred wrote: March 16th, 2024, 8:43 pm 370 Watt Solar Panels $225 each

While supply lasts. I currently have 92 left. Located in Duchesne, Utah
Theoretically, if someone had just 1 or 2 of those panels, what else minimum would be needed/recommended in regards to batteries, an inverter, or whatever one would need for this to be a working system?

Re: 370 Watt Solar Panels $225 each

Posted: October 1st, 2024, 1:00 pm
by mudflap
creator wrote: October 1st, 2024, 12:55 pm
Fred wrote: March 16th, 2024, 8:43 pm 370 Watt Solar Panels $225 each

While supply lasts. I currently have 92 left. Located in Duchesne, Utah
Theoretically, if someone had just 1 or 2 of those panels, what else minimum would be needed/recommended in regards to batteries, an inverter, or whatever one would need for this to be a working system?
Fred will have a detailed answer, but the short one is:
- batteries
- charge controller
- inverter
- some kind of safety / breakers / fuses

Re: 370 Watt Solar Panels $225 each

Posted: October 1st, 2024, 1:16 pm
by mudflap
I've been making notes. I want to put just my fridge (for now) on a solar system.

So far, I'm going to do a 24v system (12v and 48v being the other options). This will require me to get
- 2 @ 12v batteries (or 1 @ 24v battery), I like the idea that Ni-Fe or Edison batteries are bullet proof, stupid proof (they are hard to ruin completely), and don't require exotic materials (like Lithium). I don't know if I can do that right away -expediency might require me to just buy a lithium battery off amazon.
- 4 panels connected in a hybrid series/parallel configuration.
- a charge controller (PWM vs MPPT. MPPT gives you precise control and used for a large system while PWM is inefficient, but cheap, and is good for a small system)
- an inverter. I need to figure this one out.....

My fridge is rated at 120v / 5.0A. I did the calculations to figure out it uses about 2,000 watts per day, which means I need a solar system that can produce about 600 Watts (my panels are rated at 200W, so I'd need 3. I need to look at my panels - they might already be 24v, but if not, I'd need to "make" them 24v by connecting 2 at a time together....)

I would have to disconnect it completely from my main breaker panel. So I'm planning on having a big transfer switch mounted underneath my panel that can redirect (eventually) the appliances in the home over to solar. But with just one appliance for now, I'll just re-route the wiring down under the house and over to my solar array with a fuse or something.

anyway, my theory is:

- Ice is what we wanted in 2011 with that super tornado outbreak, and it's the same thing folks in Asheville want. I mean: I can distill water all day, but ice is great to have to keep things cold.

Long term, I would just preserve all our meat through canning or salting or whatnot, but ice is nice if you can get it.

Re: 370 Watt Solar Panels $225 each

Posted: October 1st, 2024, 1:21 pm
by mudflap
Just a note for anyone else out there that wants to DIY this stuff: you can't have a solar system hooked up to your regular street power / breaker box - it's illegal. This is because your system can backfeed into the utility grid and kill someone if they are working on the power lines.

since I wired my entire house all the way to the meter, I know where everything goes and what it does and whatever. I already have a disconnect switch at the street that I installed (because if the meter isn't on your house, this is the requirement around here). so in a grid down situation I would just go shut off the power at the road, and could (somewhat) easily reconnect everything over to solar.

Re: 370 Watt Solar Panels $225 each

Posted: October 1st, 2024, 3:46 pm
by Fred
creator wrote: October 1st, 2024, 12:55 pm
Fred wrote: March 16th, 2024, 8:43 pm 370 Watt Solar Panels $225 each

While supply lasts. I currently have 92 left. Located in Duchesne, Utah
Theoretically, if someone had just 1 or 2 of those panels, what else minimum would be needed/recommended in regards to batteries, an inverter, or whatever one would need for this to be a working system?
Mudflap is right about the specific components.

Think of your solar system like a flashlight. As long as the batteries are charged, the light will work. The size of your battery bank depends on what you intend to run with it. Things that are not solar friendly are electric stoves, furnaces, and air conditioners. Use propane or natural gas where you can as it is much cheaper. The cheapest, most reliable, and most efficient batteries are Deep Cycle lead acid. Marine batteries are not as good as real deep cycle batteries. A deep cycle battery can be cycled 1000 times from charged to dead. That is only 3 years if you run them dead every night. It is hundred year old technology, 80% cheaper than lithium, and if you keep them 85% charged or better they will last 20-30 years.

If you run a fridge, freezer, microwave, lights, computer, TV, etc. 5000 watts is probably plenty. A freezer generally only turns on if you open the door. A plate on the back will tell you what running amps are required. Startup will be three times that but only last for 15 seconds. A 1000 ah battery bank will run all of the above. Course if you have kids that open the fridge a lot and don't turn things off, your mileage may vary. I recommend starting with four 6 volt batteries hooked in series to create a 24 volt battery bank. Each battery is 220 ah. Hooked in series, the volts add and the amps stay the same. If you connect another string just like it in parallel, the amps will double. Remember that amp hours are different for any given voltage. So even though one single 6 colt battery is 220 amp hours and four of them hooked in series is still 220 amp hours, the battery string will last 4 times as long.

You want your batteries to stay charged, but not over charged. Otherwise you may need to add water to the batteries. Batteries that are low on electrolyte will not charge properly. Charge controllers for 12 or 24 volt systems are exactly the same price. A 24 volt system is twice as efficient. This is because converting from 12 VDC to 120 VAC is a ten times jump whereas from 24 VDC to 120 VAC is only a 5 times jump. Charge controllers cost from around $20 to a couple hundred, depending on how many panels you are charging with. Get a good controller for $150 that will take 60 amps. P=E*I or Power (watts) = E (volts or electromotive force) times I (current or amps). So a 300 watt panel produces 24 volts at 12.5 amps. So that charge controller could handle around 5 of such panels. Same panel on a 12 volt DC system would produce 25 amps. Elementary math.

Now you need to create 120 volts of alternating current for household use. This requires an inverter. Inverters for either 12 or 24 volts cost exactly the same price. Going with the most efficient system for the buck, you will choose a 24 volt inverter. I have run my house on a 5000 watt inverter for over 25 years. I can run a welder, air compressor, multiple computers, and various other crap. Larger ones are available and you can even convert to 220 VAC as well as three phase. A 5000 watt inverter will cost around $600.

I sold a system the other day for $1000. Systems are modular so you can add batteries or solar panels at any time. A neighbor come by when I first got here and told me that the power company wanted $15,000 just to connect and the power lines already crossed his property on the way to an oil well. I sold him a complete system for $5000 and he is still using it after 15 years.

Beware of Rocky Mountain Power's solar system which costs $30k and has no batteries. They are your backup. So if they are down, you are down.

Three 370 watt solar panels @ $225 = $675
One charge controller @ $150 = $150
One 5000 watt inverter @ $600 = $600
Four 220 ah 6 volt deep cycle batteries @$250 = $1000
Wire, connectors, terminals, cables, etc. = $175
Total = $2600.00 Put it together yourself

System will run a welder and air compressor right now during the day.