You might not think twice about what it takes to actually make a turn signal work, but it turns out, there's actually a cost every time you flip the stalk.
This video, put together by YouTube channel , figures out the annual price of using a blinker. Using various equations and educated estimates, the video calculates the exact amount of gasoline a car must burn to power the alternator, which in turn, gives the car electric energy to light the signals.
Of course, the amounts are extremely minimal. According to the video, every time you use your turn signal in the U.S., it costs $0.00004. Add that up over the amount of time you signal a year, and you get around $0.30. Additionally, this video doesn't take into account that side-marker signals aren't required in the U.S., meaning the costs could be even less, depending on if your car is equipped.
Additionally, the video covers the cost if your car happens to use LED lights instead. LEDs require one-sixth the electricity to work, and therefore, require one-sixth the money to operate.