Portable power stations (also sold as "solar generators") are everywhere now. Between social ads and promises of "free, endless power," it has gotten hard to separate real value from marketing spin.
To pick the right unit without regretting it, you only need to understand three simple specs. Forget the brochures, here is what matters.
1. Capacity (measured in watt-hours, Wh)
This is the size of your energy tank. A 1000 Wh battery can, in theory, run a 1000-watt device for one hour, or a 100-watt device for ten hours.
- Light camping (phones, laptops, a small cooler): 300 to 500 Wh is plenty.
- A van or home backup (fridge, coffee maker, tools): aim for at least 1000 to 2000 Wh.
Want to see it in real numbers? Pick a capacity and an appliance in the calculator below and see how long the station will actually last (accounting for losses and the fact that a fridge cycles on and off).
Runtime calculator
Cycling appliance: it only draws power about 33 % of the time (the motor stops once it reaches temperature).
Estimated runtime
≈ 1d 2h
Estimate for 1000 Wh usable at ~85 % (inverter losses + real depth of discharge). Real numbers vary with temperature, battery age, and appliance efficiency.
2. Cell type: insist on LiFePO4 (LFP)
This is the single most important factor for how long your investment lasts.
- Older batteries (standard lithium-ion) last around 500 cycles before losing range. Used often, they are done in about two years.
- Newer units use LiFePO4 (lithium iron phosphate). They take 3000+ cycles before dropping to 80% of their original capacity, close to ten years of daily use. Stop buying standard lithium-ion.
3. Inverter output (measured in watts, W)
Do not confuse capacity (Wh) with output power (W). You can have a big 2000 Wh battery that still cannot run a coffee maker if its inverter is capped at 500W.
Always check the rated output of the 120V outlets. To run anything that heats (kettle, hair dryer, microwave), you want an inverter of at least 1500W to 2000W.
