Possible new solar project

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Bacpacker

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Sorry I can't help, but I am very interested in this. On a small scale at first, then bigger. What I would like is if deeply knowledgeable people would say, "If you only want to invest $600.00 buy this" or "if you want to spend $1,500.00 start with this". or for the first $2,500.00 buy this. So I would know that I was starting with parts that I could expand off of. To start I am interested in back-up lighting.
 
We have a solar edge inverter but I'm not sure which one. We are having an issue with it not charging/seeing the battery so the company is sending someone out next week to replace it if they can't find/fix the problem. We have power from the panels during the day but with no battery, the night is "dark".
 
I'm looking into a solar system for the house. Below are links to the panels and inverter offered. Does anyone have any experience with either brand? Any keys things to be looking for? Any hints and tips are welcome.

Panels:
https://jinkosolar.com/ftp/EaglePerc G2 JKM390-410M-72HL-(V)-A3-US.pdf

Inverter:
file:///home/chronos/u-b3808de6c32d6d796e9b486ea2d5495598d7842b/MyFiles/Downloads/https___www.solaredge.com_sites_default_files_se-hd-wave-single-phase-inverter-with-setapp-datasheet-na.pdf
So much good info on the forum here.
My 2¢: you need more panel than you think.
You need more battery than you think.
 
Plan on at least 20% more watts than you have demand for. After ten to twenty years you will still have enough power to run your home. I figure on putting in 50% more generation than is called for and calculate battery needs from the panels and the time needed without sun. That will make your off grid system compatible with a "modern" life style and won't require you to adjust the way you live to a drop in overall power.
 
Plan on at least 20% more watts than you have demand for. After ten to twenty years you will still have enough power to run your home. I figure on putting in 50% more generation than is called for and calculate battery needs from the panels and the time needed without sun. That will make your off grid system compatible with a "modern" life style and won't require you to adjust the way you live to a drop in overall power.
Figuring time without sunshine is the way we designed our systems at work last year. We figured on 30 days covering thru the winter with short daylight hours and bad weather. We haven't had a station out of 30 go down yet.
Sage advice.
So many people get caught up in calculating based on at least 6 hours of usable sun every day.
That don't happen.
The two things I mentioned become very apparent when you have 4 overcast days in a row.
One other dirty little secret that is never mentioned is, as panels age their output diminishes.
Some more than others, but all of them drop some over years.
And a 100ah battery will store that amount when it is new.
When it is 2-years old, expect 80ah:rolleyes:. Add that to panels that now produce 85% of what they did when they were new and you'll get my drift.
Fortunately it is easy to add more panels and batteries later if initial planning allowed for it:).
 
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Figuring time without sunshine is the way we designed our systems at work last year. We figured on 30 days covering thru the winter with short daylight hours and bad weather. We haven't had a station out of 30 go down yet.

BacP we have had ours stored for about 5 years.So don't know till we use it.
 
A clear bright sunny day will give you about 6 hours of "usable" power with fixed arrays. If you use a tracker system you can get up to 12 hours. Winter is always problematic even with tracker arrays.
The other big issue is the temperature of the panels. They operate best between 65F and 75F. During the winter the panel gets so cold it produces very little even in bright sun. During the summer the panels can get hot enough to damage the cells. They need lots of air or other coolant to keep them working right.
 
What I have learned that makes a big difference. #1 Monocrystalline solar panels that have a high cell number that equals a higher voltage output than your batteries need, my 195 watt panels have 72 cells and put out at least 36 volts in full sunlight, I have four banks of two panels in series and I have seen up to 80 volts produced by this solar array. This is in no way overkill for a 24 volt battery system because of #2 which is an MPPT solar controller, mine is from Morningstar and it's good for 60 amps or 1,600 watts from a solar array, my solar controller can take up to 150 volts from the array and through switch settings can put out 12, 24, 36 or 48 volts to charge the batteries. #3 I use a pure sinewave inverter/charger, the output is cleaner than grid power and is very good for sensitive electronics in our home, it also makes motors run better and produces less heat in them, the Inverter/charger we use is a Magnum Energy 4,000 watt 120/240 model that can be stacked with up to four units for over 16,000 watts, I found that I could get by with just one inverter and it's capable of taking care of two large refrigerators and two chest freezers, one large and one small, also lights and celling fans. It could also run a washing machine. #4 Think small when designing what your solar system will run in the house, we have designed our system really just to run the basics, not the water heater or the clothes dryer, both of which are high wattage demands. When I put our system on the line, I found that because we had gotten the high voltage output panels we were getting better outputs than I had figured on, even on a cloudy-rainy day I was getting enough voltage and amperage to charge the battery bank and run the inverter, I've seen the system charge even when the sun was close to being down. If your plan is to run the whole house, it's going to be very costly. One other recommendation I have is that you find solar equipment suppliers close to you because you can save $100's of dollars by picking up supplies yourself, shipping is very expensive and we figure we saved at least $400 or more. The solar panels and solar controller we bought were from Grapesolar in Eugene, Oregon and just north of Eugene is where we got our inverter/charger, from Don Rowe. I have found that packaged systems can be rather expensive over a system that you are able to design, educating yourself will go a long way to saving you a lot of money. I gained much of what I have learned from AM Solar, also in Eugene, they make systems for motor homes and following what they told me I installed a very good system on our motor home, the last time we used it out on the desert in northern Nevada we stayed out six weeks and only had to charge the house batteries once by running the engine due to a very cloudy day. The best of luck on your project.
 
BacP we have had ours stored for about 5 years.So don't know till we use it.
Boy do I know how that is, we probably had ours stored for about the same amount of time, who knows considering how fast time goes by, just a few years may have been ten for all I know. Anyway, you'll get to it and then it will seem like you've had it for years.
 
My 2¢: you need more panel than you think.
You need more battery than you think.
Just for fun I have been logging the solar availability here since I posted that.
12-27 Complete overcast.
12-28 Complete overcast.
12-29 Complete overcast.
12-30 Complete overcast.
12-31 Full sun (6 hour yield)
1-01 Complete overcast.
1-02 Complete overcast with rain.

Let's say I was going to power a 100-watt load only 4 hours each day with solar (assume 100% efficiency).
How many watts would I need the panels to produce, and how many watt-hours storage would I need?

It becomes obvious why there is not a single roof in the neighborhood down here that is decorated with a panel:rolleyes:.
 
Folks, thanks for the input. Some good advice going around in the thread.

Most of these guys helped hubby and I put together up our solar at the PS site.Them plus our new forum are full of knowledge here for sure.
 
12-27 Complete overcast.
12-28 Complete overcast.
12-29 Complete overcast.
12-30 Complete overcast.
12-31 Full sun (6 hour yield)
1-01 Complete overcast.
1-02 Complete overcast with rain.
Let's say I was going to power a 100-watt load only 4 hours each day with solar (assume 100% efficiency).
How many watts would I need the panels to produce, and how many watt-hours storage would I need?
Answer:
I would need 1600 watt-hours of storage to make it to the 31st (100w x 4hr x 4 days).

On the 31st the panels would have to replace the power used from the batteries, 1600WH + the 400WH used by the load on the 31st= 2000WH with just 6 hours of sun.
2000WH \ 6 hours = 333.3 watts panel size.

Grid power down here is 10.5 cents per KWhr. The load would cost $15.33 per year to run with grid power: (.4kwh X 365days X $.105)
Even if I was able to put a system together for only $1,000 (batteries are expensive), guess how many years to break-even?
$1,000 / $15.33 = 65.2 years:eek:

In a remote location, solar is great; as a backup for when the power goes out, a lifesaver. As a replacement for grid power, not so much.
 
We built our solar system, for the present time, for emergency power only. At some point in the future it may become our only source of AC power in the case of a SHTF situation, we're just trying to stay ahead of anything that could happen and there are a lot of things that could happen due to forest fires, silver thaw which can break power poles and wires, earthquakes, trees falling and that one is common around here, and log, rock, or other big trucks that have taken out wires. We're not concerned with breaking even, we just want to stay ahead of things that can and do happen, common sense preparedness. As it is we've had our system kick on a number of time due to power drop offs, I don't have the inverter manual near by but I seem to remember that the time lapse is around 14 milliseconds, if the lights were on, all you would see is a little blink and we have one low wattage light that we keep on during the day that is strictly ran on grid power, if it's not lit or can't be turn on, we know the grid is down. I could have built a system using a generator, however, even if it ran on diesel, they still can go through a lot of fuel, I have a fairly new generator, Chinese made and noisy, due to running at such high RPM. I'd rather keep fuel for the chain saw and weed cutting, firewood and keeping the fire dangers to a minimum and leave generated power for extreme emergencies.
 
Folks, thanks for all the input on this.
After researching everything and running some numbers, we've decided to hold off for now. I'd rather pay down some debt we have first. I can build this system a little at a time as funds become available and make my own array.
One thing about the info I got, the inverter company has a thing called a micro optimizer that allows each panel to be tied in independantly, if I understand correctly, so that if a panel fails, the rest maintain what they produce and you've only lost that panel, instead of an entire bank of them. More research to be done on that aspect, but sounds promising.
Thanks again
 
Folks, thanks for all the input on this.
After researching everything and running some numbers, we've decided to hold off for now. I'd rather pay down some debt we have first. I can build this system a little at a time as funds become available and make my own array.
One thing about the info I got, the inverter company has a thing called a micro optimizer that allows each panel to be tied in independantly, if I understand correctly, so that if a panel fails, the rest maintain what they produce and you've only lost that panel, instead of an entire bank of them. More research to be done on that aspect, but sounds promising.
Thanks again

BacP hubby said this is a good book for us new to solar people. We got it when we finally got our solar only 2x 290 watt mono panels. We got complete set for little power, but hubby got book in case something happens and we need it.
 
Here is what we got.

After almost 6 yr.s we have finally got most of the equipment.

Trimetric 2030 Battery Monitor

Midnite MPPT Kid 30A Charge Controller

Kotec SK PSW 2000W Inverter

2x290 W Suniva Mono Panels




Neat fuse test,

 
Neat fuse test,
I'm impressed!
Not many people even know about Shawmut fuses.
Here's a 200 amp, 300 volt Shawmut on the DC side of the backup system that backed up 80% of the house I had in Alabama.
(the spare is sitting in the box on the disconnect switch)
IMG_2944.JPG

Yeah it ain't pretty, but it worked flawless for years.
All of the backups running at 100% could pull more than 150 amps and the battery could make more than 300 amps without breaking a sweat.
You need a good fuse:).
 
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I'm impressed!
Not many people even know about Shawmut fuses.
Here's a 200 amp, 300 volt Shawmut on the DC side of the backup system that backed up 80% of the house I had in Alabama.
(the spare is sitting in the box on the disconnect switch)View attachment 32298
Yeah it ain't pretty, but it worked flawless for years.
All of the backups running at 100% could pull more than 150 amps and the battery could make more than 300 amps without breaking a sweat.
You need a good fuse.


Glad your impressed SuprV that makes it all the more ' impressive', I found that about 6years ago when we were first looking into solar. I liked it too.:cool: Far as pretty,long as it works :cool:is what counts.
 
Answer:
I would need 1600 watt-hours of storage to make it to the 31st (100w x 4hr x 4 days).

On the 31st the panels would have to replace the power used from the batteries, 1600WH + the 400WH used by the load on the 31st= 2000WH with just 6 hours of sun.
2000WH \ 6 hours = 333.3 watts panel size.

Grid power down here is 10.5 cents per KWhr. The load would cost $15.33 per year to run with grid power: (.4kwh X 365days X $.105)
Even if I was able to put a system together for only $1,000 (batteries are expensive), guess how many years to break-even?
$1,000 / $15.33 = 65.2 years:eek:

In a remote location, solar is great; as a backup for when the power goes out, a lifesaver. As a replacement for grid power, not so much.

So your electric bill is only $15 a year?
 
So your electric bill is only $15 a year?
I wish:rolleyes:.
That is just what it would cost me to run the proposed 100-watt load 4 hours per day, every day for a year.
I should have put a disclaimer in the 10.5-cents per KWhr rate we pay.
We get that rate because we use close to 2,000 KWhrs of power each month (4 adults here).

A year's worth of that much power is $2,200 - $2,400 :eek:.
 
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