The Scenario
If you're spending a day at a location shoot — whether that's a mountain ridge for landscape photography or a festival for event coverage — you need power for your camera batteries, phone, and possibly a drone. The question is: solar panel or power bank?
We tested two representative options side by side: the Bigblue 21W Foldable Solar Panel ($68) and the Anker 737 Power Bank 20,000mAh ($148) charged beforehand. Both were used across five outdoor shoots over three weeks in varied weather conditions.
Solar Panel: Bigblue 21W
What it is: A four-fold, 21-watt panel with dual USB-A outputs and one USB-C PD output. It weighs 415g and folds to roughly the size of a paperback book.
Real-world output: In direct sunlight at noon, we measured 17-18W actual output — consistent with Bigblue's claims. At 9am or 4pm in clear conditions, output dropped to 9-11W. In partial cloud cover, it fell to 4-6W. In overcast conditions typical of coastal fog or forest canopy, output was essentially negligible at 1-2W.
The catch: The panel needs to be angled toward the sun and not shaded. Even partial shading on one section drops output dramatically because the cells are wired in series. Leaves, a camera bag strap, or your own shadow will kill performance.
Power Bank: Anker 737 (20,000mAh)
What it is: A high-capacity lithium polymer bank with 87W USB-C PD output, 65W input charging, and a built-in display showing charge level and output rate.
Real-world capacity: We measured 18,400mAh effective output at 5V/3A — about 92% of rated capacity, which is respectable. That's enough to fully charge a Sony NP-FZ100 camera battery (the 2280mAh one) approximately 8 times, or a phone like the iPhone 15 Pro about 4.5 times.
The catch: It's heavy at 630g, and it needs a power source to recharge. At home, wall charging takes about 2.5 hours via 65W PD. At a campground with solar, you'd need 2-3 days of good sun to fully recharge it via the Bigblue panel.
Head-to-Head in the Field
Scenario 1: Full-day landscape shoot, clear weather — Both worked. The power bank started at 100%, finished at 42% after charging a camera battery twice and a phone twice. The solar panel kept a phone topped up throughout the day but couldn't meaningfully charge the power bank while also running a device — the panel's output split across outputs meant neither got enough current for fast charging.
Scenario 2: Music festival, 3-day, partial shade — Power bank only. You can't keep a solar panel oriented properly at a crowd event, and shade from tents and bodies is constant. The power bank (charged before the event) was the only reliable option.
Scenario 3: Backcountry hike, multi-day — Solar wins only if you have time to stop and set it up properly. On a moving trail with tree cover, solar output was marginal. The power bank was essential for this use case, but required pre-charging at a trailhead with a power bank or vehicle USB.
Our Take
For photographers on location shoots (one day, clear weather): The power bank is the better carry. Reliable, predictable, heavy but not unreasonably so. The solar panel is a nice backup but doesn't outperform a pre-charged bank in real-world shooting conditions.
For multi-day backcountry or travel with unreliable power: The solar panel earns its place. Choose a model with at least 15W and independent cell sections so shading on one area doesn't kill the whole panel. The Bigblue works; cheaper panels with fewer cells often don't.
Best combo: A 10,000mAh power bank (250g) for everyday carry, charged from a wall plug, plus a 15W+ solar panel only when extended off-grid time is expected. Don't carry both for day trips — the weight penalty isn't worth it.