| Primary job | Stores mains electricity in advance so USB devices can be charged later. | Generates electricity from daylight to charge USB devices or refill a power bank. |
| Reliability in a UK winter outage | Very predictable if kept charged before storms and checked every few months. | Variable; short days, low sun and cloud can make output much lower than the headline wattage. |
| Indoor use | Works indoors, in the dark and overnight. | Needs direct outdoor daylight or a very bright window, with best performance outdoors. |
| Speed | Charges phones at a known rate, often with fast USB-C output on better models. | Can be fast in strong sun but slow or intermittent in weak light, especially behind glass. |
| Best kit role | Core home, car and everyday-carry backup for short to medium outages. | Secondary top-up for camping, long trips, summer outages and stretching stored power. |
| Cost and maintenance | Usually cheaper and simple to maintain by rotating through normal use. | Often costs more for a quality folding panel and needs care with cables, connectors and weather. |
| Best pairing | A head torch, emergency radio and phone charging cables. | A power bank or portable power station, so daylight energy can be stored for use after dark. |
