Solar, inverter, battery thread

biometrics

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Batteries. Every electrician/electrical engineer has told me to get two lithium batteries.
You measure the capacity in Ah or kWh, not the number of batteries. For a small system (like a Mecer modified wave manual system) it will likely be 24V so then you typically use two 12V 105Ah batteries (they are not lithium). For a larger online system like I want it’s typically measured in kWh and the one I’m looking at is 5.5kWh (this is lithium). Depth of discharge is also a factor. The non lithium you typically don’t want to discharge beyond 50% whereas with lithium you can use much more.
 

Tribs

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You measure the capacity in Ah or kWh, not the number of batteries. For a small system (like a Mecer modified wave manual system) it will likely be 24V so then you typically use two 12V 105Ah batteries (they are not lithium). For a larger online system like I want it’s typically measured in kWh and the one I’m looking at is 5.5kWh (this is lithium). Depth of discharge is also a factor. The non lithium you typically don’t want to discharge beyond 50% whereas with lithium you can use much more.
Why is that ? That you don't discharge till below 50%
 

biometrics

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Why is that ? That you don't discharge till below 50%
Those type of batteries last longer if you keep the DoD above 50%. Lithium you can go to 0% or close to it without shortening it's lifespan.
 

biometrics

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Just looked at my 2018 electricity bill vs 2021. Almost double. Now paying R1,200 just on usage and it’s going up 15% next year. Done some initial calculations and it now looks like the time to go solar. No more load shedding and free electricity. Breakeven is probably much less than I think atm since there will likely be huge increases evey year, someone has to pay that R400,000,000,000. After breakeven electricity is free. :D
 
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biometrics

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Very neat setup @biometrics. :)
That's not mine, it's an example of the installer I am engaging with. Still trying to figure out the exact configuration and then pricing. But I am now convinced it makes financial sense to go solar. I predict breakeven in FIVE years. Then free electricity.
 

Lara

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That's not mine, it's an example of the installer I am engaging with. Still trying to figure out the exact configuration and then pricing. But I am now convinced it makes financial sense to go solar. I predict breakeven in FiVE years. Then free electricity.
Convenience of not being left in the dark is preferable to recovering the cost. ;)
 

biometrics

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Convenience of not being left in the dark is preferable to recovering the cost. ;)
That's the thing. I kept on thinking about the inconvenience, but recently realised that the price of electricity has become so much (and will increase) that it makes sense to go "off grid".
 

Lara

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That's the thing. I kept on thinking about the inconvenience, but recently realised that the price of electricity has become so much (and will increase) that it makes sense to go "off grid".
The way things are going there may not be a grid. It's wise to take steps to mitigate the risk. :)
 
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