HBPowerwall (Official)

hbpowerwall

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Settings I use for my PCM60X Charge Controler
http://stores.ebay.com/Maximum-Sola...html?_nkw=PCM60x&submit=Search&_sid=140259531


image_bzlrxc.jpg
 

mbrunton

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hbpowerwall

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Yes going to 4.05 max per cell down from 4.13 - goes back to grid at 49v on the PIPs because i don't have a very balanced pack :) \
 

mbrunton

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ok, so cutoff is at approx 3.5v per pack? So you are saying that's a bit higher than it needs to be due to imbalance at the bottom of charge?
 

Andrew_art50

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Aug 6, 2018
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I'm new here but I've seen almost all of your videos and love your work. I live in Barbados, have a grid tied 5 kW PV solar system, a solar thermal hot water system, and a Nissan Leaf. I want to build a powerwall and use it primarily to recharge my car rather than using fossil fuelgrid power since I mostly charge my car early in the morning on workdays. I typically use 7kWh/day for my car so a 10 kWh powerwall will work fine for me. I'll be installing an off grid PV solar system to put energy in the powerwall and I've started to gather the parts for the powerwall. I ordered four18650 testers today and I'll start collecting batteries tomorrow. I've got a MSc in Renewable Energy Management and designed and installed my PV system so I know the thrill of building something that works with your own hands.Thanks for sharing the knowledge.
 

hbpowerwall

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Welcome Andrew_art50 - to be honest if you need 7kwh you should think about 20+ for storage - your cells will love you for it, cycling them that hard will shorten their life much faster also might need some extra power for a rainy day
 

dabeast

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Aug 23, 2018
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Hi there,

A newcomer to all the powerwall stuff here:).

I have some free laptop 18650 batteries available from work - but am only able to place 8 solar panels on my roof due to space constriction. Would a powerwall still pay for itself?

How many batteries do you roughly have in your setup? How long can you run on them when power cuts off?

Thanks!
 

grumble

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Would a powerwall still pay for itself?
Depends how much power you pull, how much sun you get and how much you spend.

How many batteries do you roughly have in your setup?
I know exactly... 1120.

How long can you run on them when power cuts off?
Depends on the charge state of the batteries. Can be days with good sun.
 

Solexx X

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Nov 16, 2017
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dabeast said:
Hi there,

A newcomer to all the powerwall stuff here:).

I have some free laptop 18650 batteries available from work - but am only able to place 8 solar panels on my roof due to space constriction. Would a powerwall still pay for itself?

How many batteries do you roughly have in your setup? How long can you run on them when power cuts off?

Thanks!

No, It won't pay for itself. If you want to go off grid part of the time, you may recover your money over time. You need a shit-ton of batteries and probably 10kW or moreof panels to make it economic. If you are doing it to reduce your footprint then yes I would say it is worthwhile. I would not bother if you are looking to save money on your electrical bill unless you are either paying a very high rate per kWh or you experience frequent outages that cost you money due to spoiled food or gas for a generator to run your water pump. This is just the start of the future of energy storage for individuals so mostly a hobby. If you get the batteries for free and go big you could go off grid by shutting off your main breaker from the utility but that will require a very big commitment of time and energy. It's what i'm trying to do for personal reasons and will require a backup generator/generators such as wind and biodiesel and woodgas. Good luck! If you are of the same mindset then this is a really good place to find information on building those batteries.Just my two cents of DIY advice. Cheers.
 

Korishan

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I disagree on the pay for itself. It will, eventually. It just depends on how much you sunk into the project that will determine how long it'll take to pay back. Even if you have cheap local power, that just means it will take longer to pay back.
For Pete, he's running fairly balanced atm, if I remember correctly. His costs saved vs costs output is about a stale mate. This is partially because he still grid connected and partially because he still doesn't have a large enough system to fully go off grid for his needs.

For me, I have one of the cheapest power in the US @ $0.13/kWh (including taxes and fees). I use about 26kWh/day, which equates to 9.9MWh per year. This costs me about $1300 in power per year. If I built a system that would take me fully off grid, it would probably take 2 - 3 years to fully repay back.
Again, this is my setup and my ROI is fairly short. Others will be different, and Pete's is definitely much longer than time than mine.
 

hbpowerwall

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[quote pid='35745' dateline='1535204745']
Would a powerwall still pay for itself?

How many batteries do you roughly have in your setup?

How long can you run on them when power cuts off?

[/quote]

If it saves a freezer full of meat & veg from going bad in a blackout Yep, it'll pay for its self :) more than one way to look at value.

4480 in service & 3000 or more waiting for space

Never really tried with the just the power off, but I got 63hours just on batteries alone with 'normal' household use. Solar was turned off for the test.
 

hbpowerwall

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Deciding to go a bit larger on my powerwall setup trying to double up the cells in each mount - looks like it'll work as planned.

 

hbpowerwall

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Bigger packs sit well!


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image_xhaneg.jpgimage_zmtwbc.jpg

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wimpie007

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Apr 8, 2017
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Are the original mounts able to carry this much weight? :-o
I guess a bigger battery is always better :-D
 

hbpowerwall

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wimpie007 said:
Are the original mounts able to carry this much weight? :-o
I guess a bigger battery is always better :-D

So far they are holding up much better than expected. The mount itself is going to be fine, more concerned with the mounts mount failing and the 7S pack falls the wall. I'm hoping to have a 7S pack installed in a week or two & will most likley build something to 'catch' the pack 1cm under it just in case. Side though maybe just a seatbelt idea might also be wise and easy to do as well....*thinks*
 

Jon

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Aug 20, 2017
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Looks good, thanks for sharing.

You could possibly put a right angle triangle wedge top and bottom to strong back the metal to help prevent the top flexing up and the bottom flexing down.
Screwed to the wall, above the top one and below the bottom one, about 20mm wide in the middle of the pack wont interfere with connecting the packs to each other.

Cheers
Jon
 

hbpowerwall

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Jon said:
Looks good, thanks for sharing.

You could possibly put a right angle triangle wedge top and bottom to strong back the metal to help prevent the top flexing up and the bottom flexing down.
Screwed to the wall, above the top one and below the bottom one, about 20mm wide in the middle of the pack wont interfere with connecting the packs to each other.

Cheers
Jon

Considered that option also have it powder coated same as the mount will still look nice and neat as appearance is important lol
 

hbpowerwall

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Finally got the shed DIYPowerwallplugged into something & it's now powering my charge/discharging process - kinda about time really

 

Korishan

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heyhey said:
Very nice mate!

How much of that 50kWh are you likely to use?

He'll use pretty much all of it
 
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