Itâ€™s always been a goal of mine to make Jalopnik the best source for turn indicator-related information and commentary on the internet. Thatâ€™s why Iâ€™m both so impressed at the work that went into this video and a bit ashamed it didnâ€™t occur to me to think this through. Finally, someone has done the math to show exactly how much it costs a driver to use their blinkers.

If the accent wasnâ€™t a clue, the video was not done by an American, which is why it suggests that cars have six indicators: in Europe and a number of other parts of the world, amber indicator repeaters are used on the front quarter-panel of a car. In the US, only four lights are required for turn indicators, so you may wish to adjust the math accordingly.

Anyway, hereâ€™s the full video, from a channel called Chapter S:

In case youâ€™re not able to watch it, the conclusion arrived at is that it costs between 21Â¢ and and 29Â¢ per year to use your indicators in the U.S.

The basic formula used to arrive at this conclusion is pleasing complex: assuming the blinkers will be used for about five seconds, with the light bulbs from the signals using about 0.08W of energy/second. Like I said, with two less lights we could possibly reduce that for American-market cars.

Then, we take the energy content of gasoline, 46.7MJ/kg, and the Chapter S team computes that a liter of gasoline contains 35MJ of energy. Then, they find that an average gasoline engineâ€™s efficiency to be about 25 to 26% efficient, and the carâ€™s alternatorâ€™s efficiency at about 70%, so when you combine the two you get the rather depressing number of 17.5% efficiency of a gas motor converting fuel to electrical power.

So, that means thereâ€™s 1.7KW of electrical energy in every liter of gasoline to go through the engine. Now, with the indicators needing 0.08W, 0.000008L of gasoline can provide that energy, but when youâ€™re using a system with 17.5% efficiency, itâ€™s going to need 0.00005L of gasoline to do it.

Then, you can compute the yearly cost with the above formula, changing the price per gallon as needed. Got it?