Need help shopping for a battery backup system.

[costaricausa]

With Black Friday around the corner we are trying to figure out what would work best for us in case of emergencies.

Context: We live in Austin, Tx which is known as a relatively safe weather place. But with the weather becoming more unpredictable each day, global warming changing patterns and making the weather worse, we would like to prepare for an emergency like the winter storm from 3 years ago.

Our current setup:
1. 15 REC360AA Black Solar panels on our roof
2. SolarEdge - 5000H-US Inverter (5000KWh inverter - https://www.solaris-shop.com/solare...ZHnPihnz_eqT62f4nSMocaV33dxCdQ5RcEJ15QfZOYsnc )
3. 15 SolarEdge Power Optimizers P401 for the solar panels
This is a 5.4KWh system. On a nice sunny day we get 25-27KWh. On a cloudy day we get 5-15KWh generated. In the future we thought of adding a solar panel gazebo, because I love how they look.

My knowledge on batteries/solar setups is limited, but I have learned a bit from Will's videos and other YT's.

With that said, here are 3 ideas I have for an emergency backup:

1. Off the shelf: Costco has the Jackery 3000 Pro with 2 100W solar panels. For $1800. This is a 3k KWh battery system.
2. DIY: Will's Cart system. https://www.mobile-solarpower.com/mobile-48v-system.html
3. A whole house backup. We had our solar panels installed by a company (Longhorn Solar). And at the times they recommended the Tesla power wall or the solar edge battery. But at $8000 + install, was too rich for us at that moment. But as I was reading Will's page on backups (https://www.mobile-solarpower.com/48v-complete-system-blueprint.html) I realized a server battery is wayyyy cheaper and larger than. For example he had this example in the page that is 3x the capacity of the SolarEdge battery and for cheaper: https://signaturesolar.com/eg4-life...door-wheels-busbar-covers/?ref=cPwLcVc0SW-BjN .

Something on the range of option 3 we would need to pay in payments, but for option 1 and 2 we have save up.

So what do you folks recommended based on this information? Has anything dealt with something similar to this? Thank you!

 

[DIYrich]

First of all, determine the max kW of power you want the inverter to produce to power your home. That will drive a lot of your decision.

You can hack a standby system, along the lines of Option 2. But, you will need to size the inverter and batteries. (cheap)

Ideally, you want to design the system to use the SolarEdge when grid is down. (more expensive, but more solar when grid is down)

I would look at an EG4 12kPV (or 18kpv). Put that between the Grid and the Main Panel. Put the Solar Edge as AC PV into the EG4. Add as much battery as you want. Probably around $5,000 plus install with one 5kWh battery. you can add more battery over time.