How Many Solar Panels Does Your Power Station Need?
Updated 2026-09-24
Solar panels turn a power station from a one-charge battery into something that can keep going for days. The question is how much panel you need, and the answer comes down to three numbers: how much energy you use per day, how much sun you get, and how many watts of solar your station can accept.
Step 1: How much energy do you use per day?
Add up the watt-hours (Wh) your devices use in a day. A fridge that averages 50W uses about 1,200Wh a day; a CPAP without the humidifier uses roughly 300–500Wh a night; a phone and laptop together are usually under 150Wh. The runtime calculator does this math for you.
Step 2: How much sun do you get?
Solar is measured in peak sun hours — the number of hours per day equal to full-strength sunlight. Across most of the US it's roughly 3–6 peak sun hours, lower in winter and in cloudy northern regions, higher in summer and in the Southwest. If you're unsure, plan on 4.
Step 3: Rate panels at about 75% of their label
A "200W" panel rarely delivers 200W. Heat, panel angle, haze, cable losses and charge-controller losses usually mean you get somewhere around 70–80% of the rated watts in good sun, and much less in partial shade or clouds.
Put it together
Panel watts needed ≈ daily Wh ÷ peak sun hours ÷ 0.75
| Daily use | 4 sun hours | 5 sun hours |
|---|---|---|
| 300Wh (CPAP, phones, lights) | ~100W | ~80W |
| 600Wh (small fridge, Wi-Fi, laptop) | ~200W | ~160W |
| 1,200Wh (full-size fridge) | ~400W | ~320W |
| 2,400Wh (fridge + freezer + extras) | ~800W | ~640W |
Round up to the next common panel size, and add more if you need to refill a drained station quickly rather than just keep up with daily use.
The limit people miss: the station's solar input
Every power station has a maximum solar input, and extra panel watts beyond that are simply wasted. That limit ranges from about 100W on the smallest units to over 2,000W on home-backup models. In our comparison chart it's the "Solar" column. A few examples from our data:
- Compact units such as the EcoFlow RIVER 3 and Jackery Explorer 300 Plus accept about 100–110W — one mid-size panel is all they can use.
- Many 1kWh-class stations take 400–600W. The EcoFlow DELTA 3 Plus is an outlier at 1,000W.
- The Jackery Explorer 2000 v2 has a 2kWh battery but only 400W of solar input, so refilling it from empty takes most of two sunny days.
- Home-backup units such as the Anker SOLIX F3800 and EcoFlow DELTA Pro 3 accept 2,400W or more.
Rule of thumb: if you plan to live on solar during an outage, pick a station whose solar input is at least one-third of its battery capacity in watts. Then a good day of sun can refill it.
Voltage and connectors
Panels wired in series add voltage; panels wired in parallel add current. Each station's manual lists a maximum input voltage and current for its solar port — stay under both, or the station will refuse to charge (or worse). Brand-matched panels and cables are the easiest route; third-party panels work fine if the voltage, current and plug (usually XT60 or Anderson) match.
Our picks
For the most solar headroom per dollar, sort the comparison chart by solar input, or browse the best 1kWh stations and 2kWh stations.