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Portable Power Station Runtime Calculator

Enter your appliances and power station capacity to calculate exactly how long it will run. Accounts for real-world efficiency losses.

🔋 Power Station
Recommended: keep 20% reserve to extend battery lifespan
🔌 Your Devices
Usable energy
Total device load
Efficiency factor
Reserve kept

How Runtime Is Calculated

Runtime = (Capacity × Efficiency × (1 - Reserve%)) ÷ Total Device Watts

Example: 1,000Wh station (LiFePO4, 90% efficient) with 20% reserve running a 100W fridge:
(1,000 × 0.90 × 0.80) ÷ 100 = 7.2 hours

Common Runtime Examples

1,000Wh Station
  • 🔋 Phone charging ×4: ~40 hrs
  • 🔌 Laptop: ~11 hrs
  • ❄ Mini fridge: ~9 hrs
  • 📺 TV + router: ~6 hrs
2,000Wh Station
  • 🔋 Full-size fridge: ~10 hrs
  • 🔌 CPAP machine: ~48 hrs
  • 📺 TV + fridge + lights: ~8 hrs
  • ❄ Basic home essentials: ~6 hrs
3,000Wh+ Station
  • 🔋 Full home essentials: ~12 hrs
  • 🔌 Window AC (1,000W): ~2 hrs
  • ❄ Space heater (1,500W): ~1.5 hrs
  • 📺 Off-grid weekend camp: ✓

Tips to Maximize Runtime

Use DC outputs when possible. Charging a laptop via USB-C (DC) instead of AC avoids the inverter efficiency loss, giving you ~10-15% more runtime.

Avoid high-wattage appliances. A 1,500W space heater drains a 1,000Wh station in under an hour. Use propane or a proper generator for heating.

LiFePO4 beats Li-ion for cold weather. Li-ion loses 20-30% capacity below freezing. LiFePO4 only loses 10-15%.

Keep 20% reserve. Draining to 0% repeatedly shortens battery life significantly. Most manufacturers recommend staying above 20%.