Need help and not sure where to begin!

[Irishbrannan]

Hi! I am new to this forum and absolutely love solar and wind generators. I want to build my own off grid small scale home system to help lower energy costs and have a backup power system capable of running a small window unit, dc low voltage lighting (e26 led) and a fridge/tv whathaveyou. I wanted to use 6 200 watt panels and a inverter along with two 200 amp renogy batteries. At first, I thought a pwm controller and 12 volt inverter to keep it simple, but now I don’t know if I should go mppt? I Also realize now a 24 volt inverter is more efficient. Is there any way to wire these 6 12 volt panels together to utilize a 24 volt inverter? I thought I could wire 3 together paralleled and then series the two strings to achieve a 24 volt load and then be able to use a 24 volt inverter correct? I also live in southwest Louisiana and face hurricane season every year and that’s why I listed only wanting to run those few things to survive on during power outages that last for weeks of not months on end. Any help or direction on wiring, charge controllers, or inverters are greatly appreciated and thanks for your time

 

[12VoltInstalls]

small scale home system to help lower energy costs

The tjing is per kWh solar is more expensive than the grid on the smaller scale.

thought a pwm controller and 12 volt inverter to keep it simple,

Mppt for sure

Also realize now a 24 volt inverter is more efficient.

At 2000 maybe not, maybe yes.

there any way to wire these 6 12 volt panels together to utilize a 24 volt inverter?

They aren’t actually 12V panels but yes 3S2P

 

[MisterSandals]

I also live in southwest Louisiana and face hurricane season every year and that’s why I listed only wanting to run those few things to survive on during power outages that last for weeks of not months on end.

Have you calculated the actual watt hours per day you expect your system to provide?

I wanted to use 6 200 watt panels and a inverter along with two 200 amp renogy batteries.

You should start using the correct units as you start working with numbers to get a better understanding as well as communicate more clearly.
Battery capacities are rated in amp hours, which is only meaningful when specified with a voltage.

200Ah @ 12.8V (nominal voltage) = 2560Wh

With your proposed 6x 200W panels, and guessing 5 solar hours:
6 x 200W x 5h = 6000Wh production per day (just more than double your battery storage)

When you figure your expected watt hour usage day to day or in emergencies, you can see how well this system matches your expectations.

 

[Irishbrannan]

Have you calculated the actual watt hours per day you expect your system to provide?


You should start using the correct units as you start working with numbers to get a better understanding as well as communicate more clearly.
Battery capacities are rated in amp hours, which is only meaningful when specified with a voltage.

200Ah @ 12.8V (nominal voltage) = 2560Wh

With your proposed 6x 200W panels, and guessing 5 solar hours:
6 x 200W x 5h = 6000Wh production per day (just more than double your battery storage)

When you figure your expected watt hour usage day to day or in emergencies, you can see how well this system matches your expectations.

Hi, thank you for your reply. I am a newbie to this and trying to learn. You state that this would produce 6000wh production per day, which is just more than double the battery capacity. Should I expand the battery bank to minimize the wastage? I have know idea of what kind of watt hour usage I need. I’ll figure that out as I get more involved Thanks for your time

 

[MisterSandals]

Should I expand the battery bank to minimize the wastage?

You have not even shared what your daily energy usage will be so its impossible to know if any of this works for your situation.

Presumably you would be using some energy during the day, all of your solar harvest does not need to get stored in the batteries.
Most of your battery stored power will be consumed outside the solar charging hours so knowing your expected use at night should be your guide to battery size.

Its impossible to build a properly sized system without knowing what it needs to do.

 

[Q-Dog]

Are you near Lake Chuck? I'm north of Lafayette and built a small backup system to cover multi-day power outages. I have since made some changes, but click on my signature to see how I got started.

I now have 10kWh battery(400ah @24 volts), 2400 watt inverter/charger, 1000 watts of solar installed ( plus another 1200 watts waiting to install). I run my refrigerator and security cameras and a couple of lights on the backup full time. If we get about a week of clouds, (so once or twice a month in Dec, Jan, Feb) I need to use the grid to add some charge to the batteries because the 1000 watts of solar can't keep up.

I have enough battery to run our critical loads for a few days. It can only run a window A/C for a few hours, basicly enough to get through the night. I don't have enough solar to charge fully flat batteries in one day. but I also have a Honda EU2200 that we can drag out for extended outages. With the generator I can run the window shaker while charging up the batteries.

Of course we haven't had another week-long outage since I installed my system.

 

[Rednecktek]

Do a search for Blurb under my username, that'll help get you pointed in the right direction. I can't grab it from my phone.

 

[Irishbrannan]

Do a search for Blurb under my username, that'll help get you pointed in the right direction. I can't grab it from my phone.

Thank you sir

 

[Irishbrannan]

Do a search for Blurb under my username, that'll help get you pointed in the right direction. I can't grab it from my phone.

Are you near Lake Chuck? I'm north of Lafayette and built a small backup system to cover multi-day power outages. I have since made some changes, but click on my signature to see how I got started.

I now have 10kWh battery(400ah @24 volts), 2400 watt inverter/charger, 1000 watts of solar installed ( plus another 1200 watts waiting to install). I run my refrigerator and security cameras and a couple of lights on the backup full time. If we get about a week of clouds, (so once or twice a month in Dec, Jan, Feb) I need to use the grid to add some charge to the batteries because the 1000 watts of solar can't keep up.

I have enough battery to run our critical loads for a few days. It can only run a window A/C for a few hours, basicly enough to get through the night. I don't have enough solar to charge fully flat batteries in one day. but I also have a Honda EU2200 that we can drag out for extended outages. With the generator I can run the window shaker while charging up the batteries.

Of course we haven't had another week-long outage since I installed my system.

Hi! Yes I’m right outside of lake charles!! I recently moved from lake charles to dry creek/Deridder area and what you have is basically what I would like to build

 

[Irishbrannan]

You have not even shared what your daily energy usage will be so its impossible to know if any of this works for your situation.

Presumably you would be using some energy during the day, all of your solar harvest does not need to get stored in the batteries.
Most of your battery stored power will be consumed outside the solar charging hours so knowing your expected use at night should be your guide to battery size.

Its impossible to build a properly sized system without knowing what it needs to do.

Thank you for your information sir. I will try and figure all that out