Trying to figure what capacity needed

[Skedaddle]

Hi all,

Complete newbie here, I've been watching some of Will's vids to try to get a better understanding of Solar which he's amazing at.

I'm trying to check if solar is feasible for what I want to accomplish, I know it would 'work' but according to my math(which is probably 100% wrong ), it's not feasible.

I'm wanting to use Solar to power my inground pool pump, which would be a Hayward Super Pool Pump, 115/230V, 1 HP. Looking on google, I see it draws anywhere from 600w to 1100w, maybe I'm wrong on that. This is not for a pool however, this is for my Hydroponic plant farm in my greenhouse, so this pump will be required to run 24/7/365.

Now my math is:

1000w x 24 hours day = 24,000wh
72,000wh

2 BB = 2400wh =
30 Battle Born batteries to get 72,000wh

----
OR if it is just 600w:
600w x 24 hours day = 14,400wh
43,200wh

2 BB = 2400wh =
18 Battle Born batteries to get 43,200wh


Hopefully, I'm a complete idiot here and my math is waaay off lol
having said all that, regardless if my math is right or wrong, would Solar be a good idea to use for this case at anyway?

Thanks for reading!

 

[DIYrich]

No comment on battle born batteries, other than cheaper better are available.

1000w 24x7 is 24kWh of battery. Allow for conversion loss of 10%.
Also, allow for days without solar (if you don't have grid backup).

Two 14kWh eg4 powerpro batteries would be good.

 

[rodrick]

Depending on your location and the size of your array you can deduct some hours off for the time the solar is making extra power also consider diy batteries this is by far the most cost effective for large batteries

 

[robbob2112]

Read the blurb below
Buy nothing until you have a plan

Post in thread 'Robbob2112 Answer thread'

Jan 14, 2025

Standard Blurb

Don't spend any money, until you have planned out the entire system. An eraser is cheap, but returns can be costly.

Planning

1. Energy Audit - what do you have to power?
2. Size the inverter for your maximum instantaneous demand (including surges).
3. Size the battery for how long you want power, when the sun isn't shining.
4. Size the PV to cover the loads and recharge the battery, when the sun is shining for your area - most in the US use 4hrs or 5 hours a day of sun
5. Trying to use old equipment you already have usually costs more in design compromises than just...

• robbob2112

• 

Battle Born is very good at marketing and charging very high prices. You can get equivalent quality for less than half the price, and when you are looking at the larger batteries 1/4 the price. To compare apples to apples look at the price per watt-hour

Watt hours are voltage times amphours.

270Ah 12V GC3 Smart Heated LiFePO4 Deep Cycle Battery Kit

The 270Ah 12V GC3 Smart Heated Lithium Battery features Dragonfly IntelLigence® smart communication technology and Integrated Heating for cold weather.

battlebornbatteries.com

12.8v * 270ah = 3456Whr
$2499 / 3456 = $0.74

EG4-WallMount Indoor Battery | 48V 280Ah | 14.3kWh | Indoor | Heated UL1973, UL9540A | 10-Year Warranty

EG4 Wall Mount Indoor Battery: 48V 280Ah, 14.3kWh capacity, heated, UL1973 & UL9540A certified, with a 10-year warranty for reliable energy storage. Available now at Signature Solar.

signaturesolar.com

51.2v * 280ah = 14336Whr
$3299 / 14336 = $0.23

Apples to apples

Note - the biggest drawback of battleborn is they only make 12v batteries. For a basic simple setup that is ok if the price is right

The most basic battery
12v100ah = 1280Whr

Battleborn 12v100ah for $749. - overpriced
Epoch 12v105ah is $349. - expensive - top tier
Litime 12v100ah $200 - middle tier
Wattcycle 12v100ah $149 - lower tier but good quality - and so far they own their mistakes

You can get no-name batteries in the same size for $110

 

[Skedaddle]

Thanks for the info so far from everyone. I would like to make it clear, I was just using the Battle born batteries cause that's what he was using as an example in his vid "How to Size your Solar Power System". I am in no way attached in using Battle born.

I guess I was trying to find help on if my math was 'mathing' as far as the w to wh and then using that to see how many batteries I would need.

again, I'm very ignorant to solar, trying to do as much research I can, I'm just trying to understand how to size up what I would need to purchase as far as batteries, charge controller, inverter and then I will need to look at the type of panels as well, as far as would I need get 600w, 400w etc panels. Because if this is going to cost like 60k, then yeah, I'm not even going to continue researching it, but if were looking at 10 to 15k or even less then that's doable.

thanks again for the help

 

[robbob2112]

There is an example for system sizing in my help pages..

high level - list what you want to run, how long you want to run it... this gets you watthours... figure that for a day and that is the minimal size of battery bank you need to run for a day.

Figure what items you want to run at the same time...wattage... that is the size inverter you need...if the loads are inductive like motors you either need to raise the size or use a low frequency inverter.

Panal array size is related to battery size... in the US we get 4 to 5 hours of full sun a day... poke your address into pvwatts.com to find that for your area.

So, if you come up with a 10,000whr battery you divide by 5 and get 2000w for an array size for charging... if you need to use power while charging your array grows by that amount

 

[Skedaddle]

This would only be for (at least for now)
"I'm wanting to use Solar to power my inground pool pump, which would be a Hayward Super Pool Pump, 115/230V, 1 HP. Looking on google, I see it draws anywhere from 600w to 1100w, maybe I'm wrong on that. This is not for a pool however, this is for my Hydroponic plant farm in my greenhouse, so this pump will be required to run 24/7/365."

So I'm coming up with 1000w x 24 hours day = 24,000wh if that is correct

 

[Rednecktek]

Yes, your math is correct, you've got the right idea. To fine tune from there:

24000wh/day + 10% inverter efficiency loss = 26400wh/day
3 days = 79,200wh

The biggest commonly available battery on the market is the 14kwh units, so:

79,200wh / 14000wh battery = 5.66 (6) batteries, or 2x batteries per day

79,200wh/ capacity / 5hrs of perfect sun = 158,400w of solar panel to refill dead batteries in one day, or 53000w of panel just for the day's usage barring clouds, bad sun, etc.

In short, you've got the concept right, and math hurts.