Browse 2 backup tools. Opening Critical Load Analysis.
Required capacity
That's roughly 1334 Wh of stored energy — about 1 hours of a typical home's power.
1,215 W total · 2× 100Ah 12V batteries · 20% buffer
| Total load | 1,215W |
|---|---|
| Estimated total surge | 4,500W |
| Required capacity | 1,334Wh |
| Battery bank | 2× 100Ah 12V batteries |
| Inverter efficiency | 92% |
| Avg hourly use | 139Wh/hr |
| Daily energy | 3,335Wh/day |
High surge load detected. Check if your inverter can handle this peak: Inverter Peak Load Surge
Note: Required Wh = average hourly consumption × backup target hours × 1.2 safety factor. Estimated surge uses running watts × 5 for high-surge devices. Battery count assumes 12 V 100 Ah cells at 80% depth of discharge and 92% inverter efficiency.
During an outage, size for circuits you truly need—fridge, lights, internet, and a few outlets—not every HVAC zone or dryer. This tool turns that appliance list into Wh capacity and a starter battery count.
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List each essential appliance with running watts and hours used per day. We average daily consumption into an hourly Wh rate, multiply by your target outage duration, and add a 20% safety buffer for inverter loss and aging.
The 12 V 100 Ah count is a planning shortcut—nominal 1,200 Wh per battery with 80% depth of discharge and 92% inverter efficiency. Pair with Home Backup Battery Sizing for voltage, DoD, and bank Ah.
List each essential appliance with running watts and hours used per day. We average daily consumption into an hourly Wh rate, multiply by your target outage duration, and add a 20% safety buffer for inverter loss and aging.
The 12 V 100 Ah count is a planning shortcut—nominal 1,200 Wh per battery with 80% depth of discharge and 92% inverter efficiency. Pair with Home Backup Battery Sizing for voltage, DoD, and bank Ah.
Q: Peak vs. average load? A: Total running watts shows simultaneous demand; Wh capacity uses your daily usage pattern. Q: Include surge? A: Use Inverter Peak Load Surge for motor start sizing. Q: Whole house? A: List only circuits you need during an outage.
List each essential appliance with running watts and hours used per day. We average daily consumption into an hourly Wh rate, multiply by your target outage duration, and add a 20% safety buffer for inverter loss and aging.
The 12 V 100 Ah count is a planning shortcut—nominal 1,200 Wh per battery with 80% depth of discharge and 92% inverter efficiency. Pair with Home Backup Battery Sizing for voltage, DoD, and bank Ah.
List each essential appliance with running watts and hours used per day. We average daily consumption into an hourly Wh rate, multiply by your target outage duration, and add a 20% safety buffer for inverter loss and aging.
The 12 V 100 Ah count is a planning shortcut—nominal 1,200 Wh per battery with 80% depth of discharge and 92% inverter efficiency. Pair with Home Backup Battery Sizing for voltage, DoD, and bank Ah.
Q: Peak vs. average load? A: Total running watts shows simultaneous demand; Wh capacity uses your daily usage pattern. Q: Include surge? A: Use Inverter Peak Load Surge for motor start sizing. Q: Whole house? A: List only circuits you need during an outage.