How Much Solar Panel Do You Need for a Security Camera?

Solar panel sizing starts with energy per day, not camera voltage or battery capacity. If a camera consumes 5 watt-hours per day, the panel must harvest more than 5Wh/day after conversion losses and poor-weather margin.

Core formula

Required panel watts ≈ daily camera Wh ÷ (peak sun hours × system efficiency). If the camera uses 6Wh/day, the location receives 2.5 effective sun hours in the design month and you assume 60% practical efficiency, theoretical break-even panel size is about 4W.

Why you should oversize above break-even

A break-even calculation assumes the average day behaves exactly as modeled. Real systems face clouds, panel dirt, shadows, cold-temperature charging restrictions and bursts of camera activity. A 6W or 10W panel may be a more robust choice than a theoretical 4W minimum.

Battery capacity is the second half

The panel covers average energy. The battery bridges nights and cloudy periods. If the camera needs 6Wh/day and you want three no-sun days with only 80% of the battery considered usable, the battery energy target is at least about 22.5Wh before additional cold/aging margin.

Panel orientation matters

Reolink recommends orienting panels toward the equator—south in the northern hemisphere, north in the southern hemisphere—and adjusting tilt for latitude to improve sun exposure. Shade can dominate the result regardless of rated panel watts.

Use the Solar Camera Power Budget Calculator to calculate panel and battery targets together.