Transparent, non-saving worksheet

Backup Planning Worksheet

Estimate the stored energy needed for a set of loads. This is a planning starting point—not equipment sizing, a runtime guarantee, or an electrical design.

Enter your assumptions

Planning estimate

Wh = watts × hours ÷ efficiency × (1 + reserve/100)

5,647 Wh

500 W × 8 h ÷ 0.85 × (1 + 20/100) = 5,647 Wh

This is the energy-side estimate from the stated inputs. It does not select a battery, inverter, transfer method, conductor, overcurrent device, or installation design.

Checks before using the estimate

Loads vary

Startup surges, cycling appliances, temperature, duty cycle, and behavior can change demand.

Usable capacity differs

Battery chemistry, discharge limits, inverter efficiency, aging, temperature, and manufacturer controls affect usable energy.

Power and energy differ

Watt-hours estimate energy. The inverter and system must also support continuous and surge watts.

Confirm locally

Have a qualified electrician or installer review transfer equipment, service, code, utility, and installation requirements.

No values are transmitted or saved by this worksheet. Do not use it as a guarantee of runtime, savings, system compatibility, code compliance, or emergency performance.