Hey Yall I have two Lithium Ion batteries hooked up in parallel to give me 200 AH of power. I have 400 watts of solar. I don’t believe I’m running enough stuff to drain it in a day. But I lost power again and can’t figure out why. It might just be an issue with not enough sun but 200 AH should last me a bit I feel. Just very confused. Everything has been working fine. Wondering if I hooked something up wrong.
I keep losing power!
- Thread starter Tater
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First thing, do a power audit so you really know what you are consuming. It's impossible for us to help you out without a lot more details on your load and set-up.
Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
Let's see. 200AH of battery and only 400W of Solar Panel. Do you actually think you can charge that battery to full with that amount of solar ?
This is too common... too much battery fr the gear to support. Maybe there is "400W rated" but reality is no solar panel will ever produce 100% of it's "Lab Rating" at best with optimal positioning you'll get 80% if that at best.
Without full disclosure of what equipment you have, the configuration / setup, getting help, suggestions or advice will be difficult to nearly impossible. Even the type of SCC (PWM / MPPT) will make a big difference... the devil is always lurking in the details.
This is too common... too much battery fr the gear to support. Maybe there is "400W rated" but reality is no solar panel will ever produce 100% of it's "Lab Rating" at best with optimal positioning you'll get 80% if that at best.
Without full disclosure of what equipment you have, the configuration / setup, getting help, suggestions or advice will be difficult to nearly impossible. Even the type of SCC (PWM / MPPT) will make a big difference... the devil is always lurking in the details.
svetz
Works in theory! Practice? That's something else
Assuming a 12 V system, 200 Ah x 12V = 2400 Watt Hours
400 W array, guessing insolation of 3 for a clear day, so 1200Wh/day generated.
As long as your consumption is less than your production, you should be okay. As @smoothJoey says, a shunt will let you see what's going into and out of your battery.
400 W array, guessing insolation of 3 for a clear day, so 1200Wh/day generated.
As long as your consumption is less than your production, you should be okay. As @smoothJoey says, a shunt will let you see what's going into and out of your battery.
I'm working on a power audit right now but wanted to put some pictures up to show ya'll what kind of set up I have.
-4X100 Watt pannels
-2x100 AH Battle Born Batteries wired in parallel
- Epever MPPT solar charge controller. I believe I have the Tracer 2215 model number circled in the photo.
- Aims 2500W Pure Sine Wave Inverter/charger
- Rocker 6 switch panel with battery monitor and 3.1A USB charger
- Marey Instant Gas Water Heater
- Dickinson Marine Direct Draft Propane heater 12V
- Flojet 12V 3.9 A water system pump
- Novakool 12V 15A compressor fridge and freezer
- Natures head 12V 1A compost toilet
-Misc 12V lights not sure of the Amp pull
-2X Dometic Fantastic Fans. Fan out, level 3 2.30A. Fan in, level 3 1.6 A. ( I am not sure the model I have but I found this info online.)
- Winegard Sensar Antenna 12V 8Amp
- Rogue Wave Wifi Antenna 12V
This is my power need at the moment. Still working on a power audit. Please let me know if this helps at all or if I'm farther from figuring this out than I thought. I really appreciate this forum and hope to increase my knowledge of solar power with the help of ya'll. thank you for taking the time to read through this. please be honest with advice.
gnubie
Solar Wizard
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Your SCC is under rated compared to the paper wattage of your panels. With a 12V battery the max possible power from the controller is 260W. That's not necessarily a problem, your array may never get to full power etc, but if it does get there for a couple of hours a day you will be missing out on notionally 280Wh of power a day. Since you already appear to be in nett deficit, every watt in is going to help.
Don't rush out and buy a different charger though. Add up all your demand first and work forward from there.
Don't rush out and buy a different charger though. Add up all your demand first and work forward from there.
I was wondering if that was the problem. I would need the 4215 model number with the 400 watts of solar I have. thanks for the reply.
Hedges
I See Electromagnetic Fields!
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How are your 4 PV panes wired?
From charge controller specs, looks to me like there are multiple choices.
Minimum MPPT battery voltage +2V; I think even all PV panels parallel will meet that. Usually, need more than 12V panel for MPPT to charge 12V battery.
Panels produce the most power aimed directly at the sun. If you manually reorient them during the day you will get more (maybe always more than this charge controller can make use of.)
If 200W of panes are aimed at morning sun, and the other 200W of panels (NOT wired in series with the first two) are aimed at afternoon sun, peak production will be about 280W, not exceeding what charge controller can handle. And it will do it more hours.
That will let you squeeze more out of the charge controller and fully utilize the panels even under best conditions.
Hedges
I See Electromagnetic Fields!
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Round trip efficiency of lead-acid is low, perhaps 70% but I've seen a wide range quoted.
Disconnect refrigerator/freezer at night, reconnect when there is full sun. That should let it run PV direct with less battery loss.
Really need to know how many Wh each device draws per day.
Does a 12V 1A composting toilet consume that 24/7 for perhaps heating? That is 288 Wh/day, perhaps 360 Wh given lead-acid round trip cost for half the day.
Nothing that can't be solved with more generating capacity.
These days we can pick up 400W PV for as little as $60, up to $200 or so.
Some of the panels are 50% more efficient that the older ones, reaching 20% vs. 13%, meaning 600W will fit in the space of your 400W.
Disconnect refrigerator/freezer at night, reconnect when there is full sun. That should let it run PV direct with less battery loss.
Really need to know how many Wh each device draws per day.
Does a 12V 1A composting toilet consume that 24/7 for perhaps heating? That is 288 Wh/day, perhaps 360 Wh given lead-acid round trip cost for half the day.
Nothing that can't be solved with more generating capacity.
These days we can pick up 400W PV for as little as $60, up to $200 or so.
Some of the panels are 50% more efficient that the older ones, reaching 20% vs. 13%, meaning 600W will fit in the space of your 400W.
My panels are wired In parallel. Last he knew ( the guy I purchased from) said they were testing at 18V. The compost toilet does do that all day for driving and ventilating. Everything was working fine for months leading up to this. I know I need to do more research but I am thinking I just need more wattage. Just hard for me to believe that 400 W (if I’m even getting all of that) can’t sustain this with moderate sun. Even on a cloudy day i should be getting something I thought. It’s just very foreign to me and I wish I had some hands on teacher that could show me!
Hedges
I See Electromagnetic Fields!
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You need a voltmeter and (large enough) ammeter if you want to measure what is really happening.
If those panels are 18 Vmp, good enough. If 18 Voc, not good enough in parallel; two in series would be better.
Your results could be very much in line with expected power consumption and production. If you spend more every day than you earn, your bank account becomes overdrawn. You need to see what your power budget is (probably break-even in the summer but not in fall or winter). Then you will probably see you either have to spend less or earn more (add more panels and another SCC)
If those panels are 18 Vmp, good enough. If 18 Voc, not good enough in parallel; two in series would be better.
Your results could be very much in line with expected power consumption and production. If you spend more every day than you earn, your bank account becomes overdrawn. You need to see what your power budget is (probably break-even in the summer but not in fall or winter). Then you will probably see you either have to spend less or earn more (add more panels and another SCC)
It's already been stated that you're not getting 400W, you're getting a maximum of 280W per the manual. Also, assuming your panels are mounted flat and you're in the northern hemisphere, as the sun moves further south, there's less solar to get.
On a cloudy day, you might be getting 50W. That wouldn't even feed your toilet for 24 hours.
Rider
Solar Addict
That's my thought, much shorter solar hours as we get towards winter, and much lower angle on the panels. What worked during the summer is falling short in the fall/winter months.
yes this is an Rv. No microwave and no tv. Fridge right now is the strongest things I have running. Other than that its 12V lights and a compost toilet fan. I Have a 15 A breaker circuit in as well.
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