Last updated: 2026-11-07
A solar powered traffic camera is a roadside camera that runs from a solar panel and battery instead of the grid. Panel watts equal daily watt-hours divided by peak sun hours and 0.75 system efficiency. A 15 W camera-and-radio load at 3 peak sun hours needs about 280 W of panel and 1,350 Wh of battery.
A camera pole stands at a junction where the nearest mains connection is a trench away, and the plan is to power the camera from the sun. Searches for a solar powered traffic camera map or a solar powered traffic camera california mostly return live-view pages for single sites, as the titles of the ranking pages show. This guide covers the other half: how much panel and battery keep such a camera running, with every input stated so you can swap in your own.
What solar powered traffic camera means
A solar powered traffic camera is a roadside camera and its network link that draw all of their energy from a solar panel and a battery instead of the mains. The camera can be a fixed unit that records vehicles, a PTZ unit that pans over a junction, or a plate-reading unit. What changes between them is the average load in watts, and that load sets the size of everything else.
The governing relation is short. Daily energy in watt-hours equals average watts multiplied by 24 hours. Panel watts equal that daily energy divided by the peak sun hours of the worst month and by a system efficiency of 0.75, a stated allowance for controller, cable and temperature losses.
Peak sun hours are the daily solar energy on the panel plane in kWh/m2/day, which equals the number of hours at 1 kW/m2 that would deliver the same energy. The figure changes with site and month, so a camera in California and a camera in a northern city need different panels for the same load. Take the value for the darkest month of operation from the site's solar resource data, not the annual mean.
The table sets out the load used through the rest of this guide. The wattages are assumptions for a small fixed camera, a wireless bridge and the controller overhead, so replace them with datasheet values for your own hardware.
| Load item | Assumed average watts | Hours per day | Watt-hours per day |
|---|---|---|---|
| Fixed camera | 6 W | 24 | 144 Wh |
| Wireless bridge | 6 W | 24 | 144 Wh |
| Controller and wiring overhead | 3 W | 24 | 72 Wh |
| Total | 15 W | 24 | 360 Wh |
The diagram shows how that energy moves from the panel to the camera.
Worked example, step by step
The worked example sizes a 15 W camera and radio load for a site with 3 peak sun hours in the worst month. The assumptions are 0.75 system efficiency, 3 days of battery autonomy, 80 percent usable battery depth, a 12 V battery, and a target of refilling the reserve within 4 days of sun after a dull spell.
- Daily energy: 15 W x 24 h = 360 Wh per day.
- Autonomy reserve: 360 Wh x 3 days = 1,080 Wh drawn from the battery.
- Battery size: 1,080 Wh / 0.8 usable depth = 1,350 Wh, which at 12 V is 1,350 / 12 = 112.5 Ah, so specify at least 120 Ah.
- Recovery energy: refilling 1,080 Wh in 4 days takes 1,080 / 4 = 270 Wh per day on top of the 360 Wh load, so the panel must harvest 630 Wh per day.
- Panel size: 630 Wh / (3 h x 0.75) = 280 W, rounded up to a 300 W array.
- Check: 300 W x 3 h x 0.75 = 675 Wh per day, which leaves 315 Wh per day after the load.
- Controller current: 300 W / 12 V = 25 A, so choose a controller rated above 25 A at 12 V.
The example assumes an MPPT controller. A PWM controller joined to a panel with a higher-voltage rating passes only the panel current at battery voltage, so the harvest falls below the rated watts and the 0.75 allowance no longer holds.
The 160 W bar only breaks even with the load, and 160 W is what the formula gives before any refill margin. The 300 W bar is the sized answer.
What most guides leave out
Most guides leave out recovery time, which is the number of days the panel needs to refill the battery after a run of cloudy days. Autonomy only tells you how long the camera survives a dull spell. Recovery tells you whether the reserve is full again before the next one arrives.
Recovery time is the reserve energy divided by the daily surplus, and the surplus is the harvest minus the load. The table applies this to the 300 W panel and the 1,080 Wh reserve from the example, at three assumed values of peak sun hours.
| Peak sun hours | Harvest per day | Surplus after 360 Wh load | Days to refill 1,080 Wh |
|---|---|---|---|
| 2 | 450 Wh | 90 Wh | 12.0 |
| 3 | 675 Wh | 315 Wh | 3.4 |
| 4 | 900 Wh | 540 Wh | 2.0 |
At 2 peak sun hours the same 300 W panel needs 12 days to refill, so a winter with spells closer together than that drains the battery step by step until the camera drops out. A buyer who sizes only for break-even finds this out in January. The fix is to size from the worst month, not the annual mean, and to read the surplus column before accepting a panel size.
Every extra watt of average load costs more than it seems. One more watt adds 24 Wh per day, 72 Wh to the autonomy reserve and 90 Wh to the nominal battery. Under the 4-day refill target in the example, that is about 19 W of extra panel per watt of load, because (24 + 72 / 4) / (3 x 0.75) = 18.7 W.
Shading counts as load in this arithmetic. A panel in the shadow of a gantry, a tree or the camera pole itself cuts the harvest, and the table above assumes full sun on the array for the whole peak-sun period. Cold also matters, so check the battery datasheet for its minimum charging temperature before specifying a pole-top cabinet.
Choosing hardware for this
Choose the hardware by four measurable numbers: average load in watts, worst-month peak sun hours, battery capacity in watt-hours and the panel input voltage window of the charge controller. Everything else follows from those four. LinkSolar is a China-based B2B supplier of custom & OEM solar panels, solar cells and mounting hardware.
Start with the load, because it is the number most often guessed. A PTZ head with heaters and infrared lighting draws far more than a fixed unit, and the guide to high-power PoE PTZ cameras with IR and cold shows how those loads enter the budget. For compatibility questions on moving cameras, the PTZ solar security camera buying notes cover the power side.
Next, match the supply voltage to the device. Many roadside cameras and radios run on PoE, and the page on a 24 V solar PoE supply for a camera and wireless bridge explains how that choice changes the battery and controller. If the camera reads plates, specifying panels and power for plate cameras adds the night-time load of the illuminator.
For temporary sites, a solar security camera trailer moves the same arithmetic onto a towable frame, where panel area is limited by the trailer footprint. For a fixed pole, give the mounting design the pole diameter, the panel tilt and the design wind speed for the site. The overview on the solar security camera page collects the product range for these builds.
FAQ
Where can I find a solar powered traffic camera map?
A solar powered traffic camera map is a search for live-view locations, and the pages that rank for it are single-site camera pages rather than hardware guides. To watch a given camera you need the page of the organisation that operates it. To power your own camera, use the formula in this guide instead.
Does a solar powered traffic camera work in California?
A solar powered traffic camera works in California when the panel is sized to the worst-month peak sun hours of that exact site, not to a state-wide average. Use the site's solar resource value in the formula, then read the recovery table to see how long a dull spell takes to repay. Roadside installations on public right-of-way also need approval from the road authority, so confirm that before ordering.
Can a solar powered traffic camera run at night?
A solar powered traffic camera runs at night from the energy the battery stored during the day. In the worked example the 1,350 Wh battery holds 1,080 Wh of usable energy, which covers 72 hours of the 15 W load with no sun at all. Night-time infrared lighting adds watts, so count it in the load budget.
Does a PTZ or plate-reading camera change the sizing?
A PTZ or plate-reading camera raises the average load, so the same formula returns a larger panel and battery. Every extra watt of average load adds about 19 W of panel under the 4-day refill target used here. Replace the 15 W figure with the datasheet average of your camera, including heaters and illuminators.
Next step
The sizing above needs four inputs before a panel and battery can be specified, and they match what the requirements form asks for: power, size, quantity and target market. Write down the average load of the camera and radio in watts, the panel space on the pole or trailer, how many sites you are equipping and the country or state where they will stand. Send your requirements with those four items and the worst-month peak sun hours for the site.