Battery load worksheet
Build a Critical-Load List Before Sizing a Home Battery
Add running watts from your own equipment. See simultaneous power, daily energy, deliverable battery energy, and static runtime without hidden appliance defaults.
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Panels, cost, savings
Backup load worksheet
Build the critical-load number before sizing a battery
Enter running watts from each device nameplate or manual. The tool keeps simultaneous power, daily energy, and static battery runtime separate.
Loads you want during an outage
No appliance wattage defaults are inserted. Verify every value on the nameplate, manual, or with a qualified electrician.
Load summary
Static backup planning estimate
Enter at least one running-watt value
Results stay blank until a load has running watts above zero. This avoids presenting an invented household load.
How the estimate works
Deliverable kWh = usable capacity × (1 - reserve) × inverter efficiency. Static runtime = deliverable kWh ÷ simultaneous running kW.
What this does not model
- Startup surge, motor locked-rotor current, 120/240 V circuits, power factor, and inverter output limits.
- Thermostat or compressor duty cycles. Static runtime assumes all active rows run continuously at entered running watts.
- Daytime solar recharge, weather, battery temperature, degradation, transfer equipment, or load-shedding controls.
- A final electrical design, backup-panel scope, code review, permit, or installer quote.
Copy the simultaneous kW into the battery planner, then ask an installer or electrician to verify surge, circuit, inverter, and transfer-equipment requirements.
SolarCalcNow provides planning estimates only. Results are not installer quotes, engineering designs, tax advice, financing recommendations, or utility interconnection approval.
Three numbers that should not be blended
Running watts describe simultaneous power while a device is on.
Daily kWh add the hours you expect each load to run.
Startup surge can exceed running watts and requires equipment-specific verification.
What to do next
Take the calculated simultaneous kW into the battery planner, then compare backup value separately from bill-savings payback.
FAQ
Common solar calculator questions
Where should I find running watts for each load?
Use the device nameplate, manufacturer manual, or a measured value. Do not rely on a generic appliance list when the actual equipment is available.
Does hours per day change the static runtime result?
No. Hours per day estimates daily energy. Static runtime assumes every active row runs continuously at its entered watts so the two concepts remain separate.
Does this calculator include startup surge?
No. Motors, pumps, compressors, and some electronics may need higher startup power. An installer or electrician must verify surge, inverter output, voltage, circuits, and transfer equipment.
Does solar recharge extend the displayed runtime?
It may, but this static estimate does not include solar recharge, weather, shading, outage timing, or battery controls. Use it as a conservative energy worksheet, not an outage guarantee.