I am in the process of building a solar tracker. This will be feedback based, using sensors to determine the location of the sun. not calculation based. (curriculum for calculation based is separate)
I want to use a couple of LED's as the sensors. pointed about 20 degrees apart, then compare the outputs. the high will be closer to the sun. then the motor will redirect to follow the sun by keeping the sensors balanced.
this will be completely off the grid so I need to use battery power. I can calculate for the motors, but am looking for the lowest energy use for the Arduino. with 4 analog inputs from the LED's I can either use an AI pin, or use an RC from the sensor and get a pulse in for a DI.
is one lower energy use ? suggestions ? I would want to compare about once per minute.
also, at night the power would be zero. I could just shut power off and wait until the sun came up and then start new each day.
looking for suggestions on how best supply power for a stand alone operation.
any help will be welcome.