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Home Solar Backup & UPS Energy Storage Calculator

Essential / eco backup runtime

27.6hrs

Your essential / eco backup runtime comes out to about 27.6 hrs.

Full load ~11.7 hrs · 9 kWh usable

Backup runtime scenarios

Full load runtime

11.7hrs

2,525 W listed

Essential / eco

27.6hrs

405 W essentials

With solar (full)

78.1hrs

23 kWh/day solar

With solar (eco)

275.9hrs

Daylight-assisted estimate

Inverter peak load & surge

Peak appliance

1,500W

Surge-class combined

2,150W

Motors / compressors

Inverter status

OK

Within continuous & surge

Battery health & lifespan

Cycle life (est.)

5,118cycles

~90% DoD LFP model

Lifespan outlook

25yrs

Annual fade

1.7%/yr

Capacity @ 10 yrs

8.4kWh

Planner recommendations

Solid emergency backup profile

Essential circuits hold ~27.6 hours with ~25-year LFP cycle outlook.

Note: Usable energy ≈ battery kWh × 90% DoD × 94% inverter efficiency. Runtime uses average blackout-day draw (watts × hours ÷ 24). Solar yield = kW × peak sun hours × 85%. Cycle life is an LFP planning model (~6,000 cycles at 80% DoD, adjusted for 90% DoD). Peak-shaving savings use your peak vs off-peak rate delta. Estimates only — validate with equipment specs and a licensed installer.

How this calculator works

How to use the Home Solar Backup & UPS Energy Storage Calculator

The Formula

Usable kWh = pack × 90% DoD × inverter efficiency. Runtime compares full-load vs essential circuits using average blackout-day draw. Surge checks compare motor/compressor starts against inverter continuous and peak ratings. Peak-shaving mode estimates monthly savings from peak vs off-peak rate deltas.

Practical Example

Q: Why is eco runtime longer? A: Essential-only circuits exclude AC and washer-class loads. Q: Does solar help during a blackout? A: Hybrid systems that island can offset daytime draw and stretch hours.

About Home Solar Backup & UPS Energy Storage Calculator

Backup runtime & surge model

Usable kWh = pack × 90% DoD × inverter efficiency. Runtime compares full-load vs essential circuits using average blackout-day draw. Surge checks compare motor/compressor starts against inverter continuous and peak ratings. Peak-shaving mode estimates monthly savings from peak vs off-peak rate deltas.

Frequently asked questions

Q: Why is eco runtime longer? A: Essential-only circuits exclude AC and washer-class loads. Q: Does solar help during a blackout? A: Hybrid systems that island can offset daytime draw and stretch hours.

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