How We Test Portable Power Stations
Every GadgetPreview recommendation is backed by a published test procedure. Here is exactly what we do, what we measure, and how we score.
1. Runtime tests
We plug in real appliances — a 12V compressor fridge, a CPAP, LED lights, a laptop — and run each station from 100% to zero. Three runs per station, and we publish the average. No manufacturer runtime claims are repeated as our own.
2. Charging tests
Each station is timed from empty to full three ways: wall outlet (AC), car (12V), and solar panels in real sunlight. We record the full curve, not just the headline “0-80%” number.
3. Solar input tests
We measure actual watts delivered from solar panels with an inline meter, in real sun, at midday. Panel marketing watts and station marketing watts are both ignored — only measured watts count.
4. UPS switchover tests
For stations with UPS mode, we time the cutover from wall power to battery with an oscilloscope-class meter. Under 20 milliseconds passes. Over that, it fails — a CPAP or desktop computer will notice the gap.
5. Cost per usable watt-hour
Every pick is judged on usable watt-hours per dollar: (rated Wh x 0.85 inverter efficiency) / street price. Capacity you cannot use is not value.
Our labeling promise
Our testing lab is being built. Until hands-on testing is complete for a model, its pick is labeled “Based on manufacturer specs” and drawn from manufacturer specifications and published owner data — never presented as a measured result. As each test completes, spec-based picks are replaced with measured data, and the test behind every number is published.
What we don’t do
- No sponsored rankings. Ever.
- No pay-to-play placements.
- Manufacturers can send test units, but it buys them nothing except a spot in the test queue.
- If a station fails a test, we publish the failure.
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