curmudgeon
New Member
- Joined
- Feb 1, 2021
- Messages
- 6
I am designing a battery backup for commercial electricity (split phase 240V 200A) powering my house. This backup is intended (instead of a generator) to bridge the times when grid power fails. The backup major components will consist of a transfer switch, batteries, and inverter. Batteries would be re-charged (and maintained) by the grid once commercial power is restored. From my limited experience, it seems that my backup system is just like the solar based systems and components discussed on Will’s DIY Solar Power channel. Is there any reason I can/should not borrow from the channel presentations but ignore the solar content?
Currently, I am choosing critical 120V circuits in my main service panel to move to a subpanel for inverter backup. I have installed an eGauge EG4115 Energy Meter and Data Logger to monitor and record various circuits/loads to help me scale the backup power requirements. Of the 9kWh of critical circuits currently in my subpanel, averaged over 30 days, only 8% of the 9kWh (9*8%= 0.72kWh) was actually consumed.
So far I am thinking about a Magnum 4400W 48VDC Pure Sine Inverter Charger MS-PAE (because it supports split phase and automatically switches between grid and inverter power) and two 24V Battle Borne batteries (because they are highly rated) in a 48 volt configuration. In a perfect world I could get around 3.3 hours of backup and maybe more by manual load shedding some circuits in the subpanel.
Batteries are a concern. Less expensive SOK Batteries (12V 100Ah at $600 each) or BigBattery Powerblock (24V 92Ah at $1200) are very appealing but their re-charge cycle rate is low and robustness less compared to Battle Borne. On the other hand, Battle Borne batteries may be overkill for a system housed in a climate controlled dry environment and using few recharge cycles relative to solar off-grid systems.
If anyone is involved (or just curious) in using batteries instead of a generator for residential backup, I would be interested in your findings and comments.
Currently, I am choosing critical 120V circuits in my main service panel to move to a subpanel for inverter backup. I have installed an eGauge EG4115 Energy Meter and Data Logger to monitor and record various circuits/loads to help me scale the backup power requirements. Of the 9kWh of critical circuits currently in my subpanel, averaged over 30 days, only 8% of the 9kWh (9*8%= 0.72kWh) was actually consumed.
So far I am thinking about a Magnum 4400W 48VDC Pure Sine Inverter Charger MS-PAE (because it supports split phase and automatically switches between grid and inverter power) and two 24V Battle Borne batteries (because they are highly rated) in a 48 volt configuration. In a perfect world I could get around 3.3 hours of backup and maybe more by manual load shedding some circuits in the subpanel.
Batteries are a concern. Less expensive SOK Batteries (12V 100Ah at $600 each) or BigBattery Powerblock (24V 92Ah at $1200) are very appealing but their re-charge cycle rate is low and robustness less compared to Battle Borne. On the other hand, Battle Borne batteries may be overkill for a system housed in a climate controlled dry environment and using few recharge cycles relative to solar off-grid systems.
If anyone is involved (or just curious) in using batteries instead of a generator for residential backup, I would be interested in your findings and comments.
