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How much space should I allot for solar components?

porkchopexpress

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I'm designing a mini-cabin/accessory sleeping quarters to complement my lake house. It's going to be 12' x 10' with a small loft and I want it to be powered by solar. Main lake house is currently on the grid but I thought it would be cool to have this entirely separate.

I'm a novice and am reading through various tutorials, studying Youtube videos of DIY solar installations and all that. I have a ways to go in getting familiar with the technology and designing a solar power system. However, I was hoping to get some sort of idea on how much space I might need to allot within the mini-cabin for the components... like, if they're going to be behind some sort of panel, recessed into the floor, etc. Including whatever batteries might be needed. In fact, I'm guessing battery space might be the most significant factor? Can anyone give general pointers on this?

Components being powered would include a ceiling fan, charging a laptop and smartphones, some LED lighting and maybe a 32" or so energy-efficient TV/DVD player. Calculator I found online gave me 2176 watt-hours per day, so my guess is I'd round this up to about a 2400 watt system?
 
Assuming: all of your appliances are 120V AC. I have a 24V, 200Ah LiFePo4 battery size about 21"x 9.5"x8.6", weigh about 96lbs. An Inverter 3000/6000W pure sine wave dimension about 22"x9.5"x4" about 10lbs. These are the major components. Other such as charge controller MPPT is small 7.3"x5"x2.5", weigh about 3lbs, disconnect fuse, wires, terminal block (if necessary). Solar panels can be mounted on the roof or on the ground. You need to double up your calculation of usage/day to count for the rainy and heavy cloud day. I think 24V and 200Ah LifePo4 battery will give you an additional day.
 
Assuming: all of your appliances are 120V AC. I have a 24V, 200Ah LiFePo4 battery size about 21"x 9.5"x8.6", weigh about 96lbs. An Inverter 3000/6000W pure sine wave dimension about 22"x9.5"x4" about 10lbs. These are the major components. Other such as charge controller MPPT is small 7.3"x5"x2.5", weigh about 3lbs, disconnect fuse, wires, terminal block (if necessary). Solar panels can be mounted on the roof or on the ground. You need to double up your calculation of usage/day to count for the rainy and heavy cloud day. I think 24V and 200Ah LifePo4 battery will give you an additional day.

Thanks. Does a product like this generally match the setup you're referring to? (www.amazon.com/gp/product/B08YR8XF4W/) Looks like there are a whole bunch of options for complete kits or piecing together when it comes to that point.
 
The link, you provided, is kind of expensive (~$3k plus tax, battery not included). What I have are 2 panels of 320W (mono crystalline) LG, 1 LiFePo4 24V-200Ah battery, Victron MPPT 100/30, Giandel 4000/8000W power inverter and wires/fuses: it costs me about $2,500. I built it as portable solar generator. Panels and battery are on the dollies since they are heavy or wide/tall. It took about 9 hrs to fully charge the battery from 10% capacity to 100%. My 2 panels can produce about 4,100Wh/day (in series). This can satisfy your 2400W daily req.
PS: I did oversize the inverter (cost about $500) to count for future emergency needs such as blanket heater for harsh winter, mini microwave or few fans (in hot summer).
 
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For something this small you do not need anything huge. It is not like you are running a fridge, well pump and other heavy draw devices. Form your description the biggest thing will be the TV & DVD and possibly a laptop... I'd wager you'll want AC and a few more things later as well...

An All-In-One which is capable to 2000W would serve you quite well and be easier to install.
120V/20A=2400W 120V/15A=1800W

Something to appreciate for Context. I sit here right now, 100% solar powered & offgrid, I have an HP EliteDesk i7 Computer running, an LG 47" LED Tv as a Screen, ax XplorNet Satelitte Modem, Router/Hub and a couple of wall wart devices and I am pulling 6.4A from my 24V Battery Bank which also includes the Inverter draw. 120VAC/139W/109VA +/- output from the Inverter.

An All-In One, 4-6 Solar Panels (depending on watts and what the AIO can accept), 1 or 2 Batteries depending on chemistry & size wanted.*
* Size wanted will depend on how many watt hours will be used in a normal day of use, + 10% margin.
 
Thanks. Does a product like this generally match the setup you're referring to? (www.amazon.com/gp/product/B08YR8XF4W/) Looks like there are a whole bunch of options for complete kits or piecing together when it comes to that point.
Those Eco Worthy are very Over Priced and total Junk.
Do Not Buy!
The charge controller is a fake MPPT and not capable of 60A.
Inverter is junk.
Do not buy a kit.
That kit is a bad joke.
 
Those Eco Worthy are very Over Priced and total Junk.
Do Not Buy!
The charge controller is a fake MPPT and not capable of 60A.
Inverter is junk.
Do not buy a kit.
That kit is a bad joke.
Agree. I like to pick and choose the quality components (based on reviews and + experiences) since I will depend on them. It took me 3 months just to do research and bought the components as they were on sale or at a good deal.
PS: Quality MPPT is very important. I read some reviews comparing Victron MPPT with Epever MPPT. Victron came up 60% faster in charging time vs. Epever. The Victron cost is about 3-4 times more expensive. It is necessary to have your battery charged faster since the weather is unpredictable.
 
Assuming: all of your appliances are 120V AC. I have a 24V, 200Ah LiFePo4 battery size about 21"x 9.5"x8.6", weigh about 96lbs.

So if I'm understanding correctly, if I had the 24V 200Ah, and added a second identical battery in parallel, it would take me to 24V 400Ah?

I was using the calculators at (https://www.altestore.com/store/calculators/load_calculator) and it suggested 399Ah capacity... but that calculator is talking about lead acid batteries. My understanding was, those only have 50% of the efficiency of lithium so I then cut the 399 in half?

But for the purposes of design, I am thinking if I allocate enough space for two such batteries, I should be good.

Incidentally, that calculator in the link seemed pretty helpful, laying out numbers that I'm able to grasp even at a novice level. It looks like it's a decade or more old though (still listing wattage consumption of VCRs, not really accounting for newer battery technology etc.) Any recommendations for a newer resource but along the same lines?
 
If you're looking for space, my RV build has 4 golf cart batteries, 3 charge controllers, a combiner box, and an inverter. All that takes up about half my pass through storage in my RV. So perhaps 5' X 2 ' X 3'. A lot of builds are more compact so space could be saved.

24 volts and 400 AH is twice the battery power of my build.

For some of my spacing I did a to scale design for my Power Board moving parts around. When I did this I was shocked at how big some parts were. I watched a You Tube video of a real tight build where he did 3D cardboard cutouts prior to receiving his parts.
 
So if I'm understanding correctly, if I had the 24V 200Ah, and added a second identical battery in parallel, it would take me to 24V 400Ah?

I was using the calculators at (https://www.altestore.com/store/calculators/load_calculator) and it suggested 399Ah capacity... but that calculator is talking about lead acid batteries. My understanding was, those only have 50% of the efficiency of lithium so I then cut the 399 in half?

But for the purposes of design, I am thinking if I allocate enough space for two such batteries, I should be good.

Incidentally, that calculator in the link seemed pretty helpful, laying out numbers that I'm able to grasp even at a novice level. It looks like it's a decade or more old though (still listing wattage consumption of VCRs, not really accounting for newer battery technology etc.) Any recommendations for a newer resource but along the same lines?
If you're looking for space, my RV build has 4 golf cart batteries, 3 charge controllers, a combiner box, and an inverter. All that takes up about half my pass through storage in my RV. So perhaps 5' X 2 ' X 3'. A lot of builds are more compact so space could be saved.

24 volts and 400 AH is twice the battery power of my build.

For some of my spacing I did a to scale design for my Power Board moving parts around. When I did this I was shocked at how big some parts were. I watched a You Tube video of a real tight build where he did 3D cardboard cutouts prior to receiving his parts.
Since your main goal is to conserve the space, then your best choice is LiFePo4 battery, not only efficient (can be used up to 90-80% of its capacity), but also 1/3 to 1/2 less weight than lead acid battery. Lifepo4 battery is also last longer twice than lead acid battery if you care for it properly. I know the cost is much more, but if your goal is to conserve the space LiFePo4 is the one. Yes, if you parallel the battery you will get more capacity. You need to understand to parallel batteries will take space and you need to do it properly. Battery is a dangerous stuff.
 
Porkchop - Yes, 2 in parallel will double your AH and voltage stays the same. Two in series doubles your voltage and AH remains the same. I have 4 200 AH LiFePO4 batteries in my bank and after over a year on them have only had to run the generator a few times. Just make sure you have enough panels, actually over-panel - they are cheap! I have 2.8 KW of panels and a MidNite Solar Classic 200SL CC. My battery box is about 24" wide, 48" long, and probably 36" high and finished like a cabinet with lift-off top. My chargers and Samlex 1500W inverter set in the top of the box so the only solar component that is seen is the CC on the wall by AC breaker panel.

If interested I could post up a pic...
 
OK, here's a couple of pics. One showing just the box and another with the breaker panel and Classic 200 on the wall. Sorry about the size but I don't have anything up here on my laptop to resize them with.
 

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