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Solar design  RSS feed

 
Posts: 20
Location: san bernardino, california
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I wanted to run the system by you all before buying the rest of the components. First I'm building an off grid system. I already have 12 x 255 watt Canadian panels for a total of 3000w. In the future I want to add another 1500w. I want to build a 48v battery bank. I don't know my power needs yet but currently we use about 300kW to 600kw a month with normal living on grid which includes the a/c in the summer. For the offgrid house I want to add a 12v system for lights off the 48v bank using a step down converter or by another charge controller to a 12v battery.

Here's what I want to get let me know if it will work or if it's just not going to work right.
8 x Trojan t 105
Midnight Classic 150
Conext XW+ 5548 By Schneider
golf cart DC Converter 48V to 12V Step Down from China

That's what I am thinking so far what do you think
 
Posts: 13
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The battery bank will give you a total of 12kw of energy. Typically, we never want to discharge lead-acid below 50% so that gives you 6 kw usable. I size my battery bank to provide 3 days without solar input so in your case that's 2kw/day available.

As long as your have a little more than 2 hrs of solar insolation per day, you should be able to top off your 50% drained bank in one day.

I've got inverter envy. That's one sexy inverter and seems appropriately sized for the the rest of the system.

Nice!

Austin Laureski wrote:I wanted to run the system by you all before buying the rest of the components. First I'm building an off grid system. I already have 12 x 255 watt Canadian panels for a total of 3000w. In the future I want to add another 1500w. I want to build a 48v battery bank. I don't know my power needs yet but currently we use about 300kW to 600kw a month with normal living on grid which includes the a/c in the summer. For the offgrid house I want to add a 12v system for lights off the 48v bank using a step down converter or by another charge controller to a 12v battery.

Here's what I want to get let me know if it will work or if it's just not going to work right.
8 x Trojan t 105
Midnight Classic 150
Conext XW+ 5548 By Schneider
Golf Cart DC Converter 48V to 12V Step Down from China

That's what I am thinking so far what do you think

 
pollinator
Posts: 684
Location: Richmond, Utah
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That looks great! Basically the system I installed for an off-grid client about 4 years ago. He has a little trouble getting enough power in winter up here in northern Utah, but I'll bet you'll be fine in so. Cal. One thing that DIY installs don't always look into is battery storage. Ventilation and temperature control are essential to safe operation and long battery life. Good luck
 
Posts: 632
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Just to avoid a bit of confusion as you are sizing your system,

Kilowatt is a unit of power. A microwave might have a power rating of 1.2 kw.

A generator might have a power rating of 6 kilowatts.

A solar panel might produce 120 watts, or 0.12 kw.

Kilowatt hours is a different thing.

120 watts x 4 hours = 480 watt hours, or 0.48 kilowatt hours.


Kilowatt hour (kwh) is a measure of power x time. So a battery bank is often rated in kilowatt hours, not kilowatts.


But aside from the nitpicky little units thing, you are asking all the right questions.

Carry on,

finest regards,

troy
 
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