Portuguese Prepper
Emergency Power Calculator: How many watts do you actually need?
Before you spend $1,000 on a generator, you must do the math. Buying a unit that is too small is a waste of money because it will trip its overload protection the moment you turn on your fridge.
To size your system correctly, you need to understand two numbers: Running Watts (the power needed to keep a device on) and Surge Watts (the spike of power needed to start the motor).
Phones/Laptops have 0 Surge Watts (Easy to power).
Fridges/ACs have massive Surge Watts (Hard to power).
Rule of Thumb: Buy 20% more capacity than you think you need.
Typical Appliance Power Ratings
Use this chart to estimate your total load. Add up the running watts of everything you want to turn on at the same time, then add the *highest* single surge watt number.
| Appliance | Running Watts | Surge Watts |
|---|---|---|
| Smartphone | 5-10 W | 0 W |
| Laptop | 50-100 W | 0 W |
| LED Lamp | 10 W | 0 W |
| Refrigerator | 150 W | 1,200 W |
| Sump Pump (1/3 HP) | 800 W | 1,300 W |
| Window AC (10k BTU) | 1,200 W | 2,000 W |
| Microwave | 1,000 W | 1,500 W |
Tier 1: Tech Only (Under 300 Watts)
Goal: Charge phones, keep the Wi-Fi router on, run LED lights.
Solution: You do not need a gas generator. A small Portable Power Station (250Wh–500Wh) is perfect. It is silent, cheap, and can be recharged by a small solar panel.
Tier 2: Fridge & Essentials (1,000–2,000 Watts)
Goal: Keep the food cold, run a CPAP machine, and power a fan.
Solution: You need a unit capable of handling the 1,200W surge of the fridge. Look for a Solar Generator with 1800W+ Output or a small 2000W Inverter Gas Generator.
Tier 3: Whole Home (5,000+ Watts)
Goal: Central AC, water heater, well pump, and kitchen.
Solution: Batteries are too expensive for this. You need a large Dual Fuel (Gas/Propane) Generator wired into your house via a transfer switch.
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