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Energy

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🔋Energy

How long do light, phones and radio last when the power is out?

  • Record storage: power banks (mAh), batteries (Wh), car battery (Ah), solar panel (W), generator (W). The app converts everything into usable watt-hours with realistic deductions.
  • Consumers: phone charging, radio, headlamp, laptop, fridge, fan heater with typical daily need.
  • Result: days of power for the essentials, solar top-up calculated conservatively (winter, clouds, angle).
  • Feeds into endurance.
  • Locations: if an entry has a storage location, a filter row appears at the top (Flat, Holiday home …). Stored watt-hours, supply and "That's enough for" then apply to the chosen location — what's in the holiday home doesn't help in the flat.

Power cut and blackout: how the app calculates

In a blackout it does not matter how many power banks are in the cupboard, but how long the radio runs and how often the phone gets charged. So the app converts everything into watt-hours (Wh).

  • Power bank: mAh × 3.7 V ÷ 1000. A 10,000 mAh power bank therefore gives about 37 Wh, not 10 Ah at the USB output.
  • Car battery: Ah × 12 V, but only half counts as usable. 60 Ah gives roughly 360 Wh.
  • Battery: Wh are taken as entered.
  • Deduction: Of everything stored, 85 % counts. Example: 37 Wh gives about 31 Wh usable, which is two phone charges (15 Wh each) or around 10 hours of radio (3 W).
  • Solar and generator: They store nothing, they supply power. Solar counts only at a quarter of its rated output, a generator at full output.

Prepare before the power is gone

Enter each source with quantity and storage location. The "Charged" switch reminds you that power banks drain by themselves; an entry with the switch off shows the tag "empty?". The list "That's enough for" shows at once what is carried: headlamp (3 W), room lamp (8 W), laptop (45 W) and fridge (35 W daily average). A fan heater and a kettle at 2000 W each blow through any battery supply and only make sense with a generator. Record generator fuel separately under supplies.

Honest limits

All values are approximations. The app does not measure charge, it calculates from what you enter. Cold lowers battery capacity, converters lose energy, in winter a solar panel delivers only a fraction. Better to calculate cautiously than too optimistically. Never run a generator in an enclosed space (carbon monoxide risk).

Energy
Energy
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