An Arduino UNO microcontroller measures the temperature and moves the actuator.
It uses simple hysteresis control so as to make few adjustments during the day.
It also sends the temperature wirelessly to another Arduino NANO inside the house.
This image was taken before the addition of the ambient light sensor.
Note on wiring:
Transmitter: DAT to digital pin 12, + to 3.3 volts, - to ground, Short antenna
Receiver: DAT to digital pin 11, VCC to 5 volts, GND to GND, Long antenna