Home grid-tie Solar is SunRun with SolarEdge. Considering DIY generator/battery

[TedH]

SunRun installed a 9.2kW rooftop (7.6kW inverter) system for $42K. They will upsell name-brand battery banks for serious coin. I'm inclined to move kitchen, laundry and Home AC system breakers into a separate breaker box along with 100a breaker (half of the home 200a service). My goal would be to have failover for the key home systems/areas but not the whole home. The 100a service would come through the 100a breaker, to an inverter/charger (with 48v DC battery bank attached) and then to the three home systems areas.

Has anybody considered such a set up? I have a 24v Inverter/charger (Aims 6000watt continuous/18000 surge) to serve two 50amp hot legs. Do I need a second inverter or just get a LARGER inverter/charger? My battery bank would be 24v (three 24v packs of 8, 304ah cells from 304ah EVE lifepo4 cells, bms, balancers and hardware) in a sealable shelf configuration similar to the 'Off Grid Garage' fella (he has 48v) for about 22kW battery backup. The inverter/charger has ATS. I would save close to $5K DIY and in the footprint of ONE 7Kw Tesla Powerwall.

Thoughts? I've not fully designed my solution but I have similar DIY on my bus (15.5kW - 24v, 600ah pack).

 

[TedH]

I am also considering a 'less DIY' solution around my Aims inverter/charger and an enclosed rack of six, 24v, 5kW Lifepower case power cells at $1,500 each (just saw a price drop to $8.1K). Considering it would be a 30kW storage solution, it would be nearly 4 times the capacity of the $7-10K solutions and much smaller footprint.

 

[BentleyJ]

System design has to be based on whether your not you wanted the SolarEdge system to continue operating when the grid is down. If so then the inverter would have to be grid interactive, UL1741SB compliant model of inverter. The grid-tie system would then be moved to the subpanel and would be AC Coupled to the new inverter.

The Aims inverter will work to power the new, critical loads subpanel in an outage but would not be able to form the micro-grid and control the SolarEdge system.

 

[TedH]

System design has to be based on whether your not you wanted the SolarEdge system to continue operating when the grid is down. If so then the inverter would have to be grid interactive, UL1741SB compliant model of inverter. The grid-tie system would then be moved to the subpanel and would be AC Coupled to the new inverter.

The Aims inverter will work to power the new, critical loads subpanel in an outage but would not be able to form the micro-grid and control the SolarEdge system.

Agreed. I see the SolarEdge compatible solutions have a $$$ premium that hurts my wallet :D