Solar Powered Camera Trap

This post explains to create a solar powered camera trap. We recently picked up a basic, simple to use camera trap from Stealth Cam (the STC-P12). We wanted to see if we could run the wildlife camera off of a small solar panel as it runs off of 8 (!) AA batteries and we hate disposing of AAs. We could use the 12V DC input on the bottom of the cam, but didn’t want to use one of our large laptop style systems to charge it. Instead we used one of our basic kits and boosted the 5V USB output up to 12V.

Parts list:
– Stealth Cam STC-P12
– 6 Watt Solar Charger Kit (3.5 Watt Kit would probably work also)
– 2 x Extension cable
– 5 to 12V Boost – lots of these on eBay
– Waterproof Case – we like the Nanuk 330
– Epoxy or waterproof gland

Determining power requirements:
Before building the system, we wanted to first make sure that the boost from 5V would work. We connected the system through a Drok inline multimeter and then our power supply to confirm the results. We measured:
– a bit less than 1 Watt power consumption for a second while the system was taking a picture
– 0.72 Watts while camera was in standby for about 60 seconds after picture
– Less than 0.005 Watts when camera went into sleep mode

This was well within the parameters of our system, so we proceeded with the build.

Assembly:

Power in: We cut one of the extension cable and drilled a hole in the case so that the cable just fit. We then spliced that cable to a MicroUSB cable to connect to the Voltaic V15. To test this portion, point the panel at the sun and the charge indicators on the Voltaic battery should light up in sequence.

Power from battery to camera: First, we cut the output USB cable (included with the V15) to expose the positive and negative wires and soldered them to the boost circuit. Then we cut a second cable, drilled a hole through the case and connected the cable to a 5.5 x 2.1mm plug.

This is what the system looked like when complete. The battery fits snugly inside the case.

Always On Mode – Important to prevent battery shutoff!
Our battery is designed to shut off after 20 minutes if nothing is drawing power. You want to override that setting in this sort of 24 x 7 setup. To switch to Always On mode, hold the power button down for 7-8 seconds until the lights flash three times. Now the battery stays on no matter what. To double check that you are in Always On mode, double click the power button. If the power stays on, you are in Always On mode. If not, hold the power button for another 7 seconds.

More testing and field use:
Before taking it out to the field, we tested it in a Brooklyn backyard with a pumpkin as bait. We got mostly squirrels plus a few sparrows.

We then installed it on the edge of a field where it looked like there were was a deer path.

The edge of the woods are often brush filled and there wasn’t a perfect spot to hang the panel. We hung the panel on a branch and pointed it toward the sun.

Results:
From a power perspective, it worked great. The Voltaic battery was completely full after a cloudy January in the field.

From a wildlife perspective, we only caught one deer plus pictures of ourselves when we went to check on it. I’m not sure if this is because the motion sensor was only so-so, the camera wasn’t in a great spot or the deer just weren’t that active. We’ll continue to test.