Emergency solar setup on a budget

[Swissguy]

Hello community,

I am new here and I started to research into an emergency power generator to use in case of a blackout.

I would like to purchase a 12V 280Ah EVE LiFePO4 battery pack 4S for this purpose and would like to be able to charge it efficiently. I was thinking to get a 600W or 800W solar panel system.

Now I have some issues figuring out how to set up a system with 800W to charge a 12V battery.

I wanted to go for an all in one solution but the 12V ones don't support that power on the solar panels, also I wanted to safe the money for the high amp cables and BMS.

It seems to me that there are some affordable 24V all in one solutions on aliexpress but I don't want to get a 8S system as that would be already over my budget.

Any suggestions on what I could do?

Should I go DIY with an MPPT and an inverter, or go for the 24V All-in-one and using a 12V to 24V converter connected to the battery?

Thanks for your suggestions

 

[Bubba1]

What would you need to run in a power outage? Fridge and freezer. Maybe a few lights and a fan.

 

[Bud Martin]

You can use 600W on the 12V system, the MPPT will just clip the power. My firt system was MPP SOLAR PIP-1012 which is rated at 500W for 12V system, I had three 230W panels (I started with just two panels first but was not happy with the power I was getting in real world setup) connected and able to get 500W with no issue and it is also good when it is cloudy.
What is your power requirement?

 

[sunshine]

Now I have some issues figuring out how to set up a system with 800W to charge a 12V battery.

I wanted to go for an all in one solution but the 12V ones don't support that power on the solar panels

Panels directly connected to the batteries are a possibility.
Proviso: There must be a constant load in the system. The larger the constant load the more unregulated panels in proportion to the regulated (by CC) panels the closer the charging parameters are followed.
The panels need blocking diodes & closer the panel Voc is to the system voltage the more efficient.

Works ok on my little 12v pwm lead acid system.

 

[Swissguy]

What would you need to run in a power outage? Fridge and freezer. Maybe a few lights and a fan.

Hello, yes. A small fridge charging our mobile phones and laptops a few hours per day. Some lights at night and TV for a few hours + reserve for cloudy days. I figured that around 3500 Wh should be fine

 

[Swissguy]

You can use 600W on the 12V system, the MPPT will just clip the power. My firt system was MPP SOLAR PIP-1012 which is rated at 500W for 12V system, I had three 230W panels (I started with just two panels first but was not happy with the power I was getting in real world setup) connected and able to get 500W with no issue and it is also good when it is cloudy.
What is your power requirement?

Hello Bud, thanks for the reply. See my power requirements in my previous post.

What were your amps in the system you described?