How we rate portable power stations
Every power station on PowerScope is described with the same fields and rated with the same rules, so any two pages can be compared honestly.
Where the specs come from
We start from the Amazon listing, then convert every value into the same units (Wh, W, minutes, pounds, cycles). Amazon listings are often incomplete or mix in specs from other models, so when a spec is missing or inconsistent we check the manufacturer's page or a reputable independent review for that exact model, and we list those sources on each page. If a value can't be verified anywhere, we show a dash (—). We never estimate a spec to fill a chart.
Capacity, output, surge and charge times are manufacturer claims. Independent tests typically find 80–90% of rated capacity usable at the AC outlets, which is why our runtime estimates use 85%.
The seven editor scores
Scores run from 0 to 10. Four are calculated from the spec sheet on fixed scales that are the same across the whole site, so adding new power stations never changes existing scores. Three are editorial judgments.
| Score | How it's calculated |
|---|---|
| Capacity | Logarithmic scale on rated watt-hours: 100 Wh = 0, 3,600 Wh = 10. |
| Output | Logarithmic scale on continuous AC output: 150 W = 0, 3,600 W = 10. |
| Solar input | Logarithmic scale on maximum solar input: 50 W = 0, 1,600 W = 10. Shown as n/a when the maximum isn't published. |
| Portability | Logarithmic scale on weight: 100 lb = 0, 4 lb = 10. |
| Charging | Editorial: time to full (or to 80%) from a wall outlet, plus options like car, dual AC + solar and app-controlled fast charging. |
| Battery life | Editorial: cell chemistry (LiFePO4 vs other lithium), rated cycles and to what capacity, and warranty length. |
| Value | Editorial: price per watt-hour and per watt at our price check, weighed against features, seller and the owner-review track record. |
The editor score shown on cards is a weighted average: capacity 20%, value 20%, output 15%, battery life 15%, charging 10%, solar input 10% and portability 10%. An axis we can’t verify (shown as n/a) counts as 0, so missing data never makes a station look better.
Runtime estimates
The runtime calculator and the "How long it runs" tables use typical device draws (for example 40 W for a CPAP without humidifier, and a full-size fridge averaging about 1.3 kWh a day). Your devices may differ, so the calculator lets you edit every number.
Owner reviews
We read the Amazon customer reviews for each listing and summarize the recurring themes, good and bad, in our own words. We don't write, edit the meaning of, or invent reviews.
Prices
Prices are a snapshot from Amazon.com on the date shown next to them. They change often, so the price on Amazon at the time of purchase is the one that applies. We only call something a deal when Amazon shows a real discount.
Money
We earn a commission when you buy through our Amazon links. Commissions never affect scores or rankings. See our affiliate disclosure.