user651: Does using the delay function use any less power than spinning in a polling loop on a timer?

user8175: The answer is probably "they are equal" because what the CPU is doing is less than 1% of power draw. In order to save power while waiting you can put the chip to sleep. Assuming you have an Arduino uno, this post contains sample code about sleeping and current consumption. http://forum.arduino.cc/index.php?topic=78430.0
Maybe explain what you are doing (what size battery you have) and we can add some advice about ways to save power 

user6740: That depends very much on how delay() was written (and how it will be written in the future!). There are "sleep modes", which will reduce the power consumption of the arduino - these are one of the best way to reduce power consumption. Delay() may or may not activate these. If not, there could be a replacement Delay() function that could do this.
If you want to reduce power, check out http://www.gammon.com.au/power - this is an excellent step-by-step tutorial on how to reduce power consumption from 50mA down to 288 µA

651: <p>Does using the delay function use any less power than spinning in a polling loop on a timer?</p>
 8175: <p>The answer is probably "they are equal" because what the CPU is doing is less than 1% of power draw. In order to save power while waiting you can put the chip to sleep. Assuming you have an Arduino uno, this post contains sample code about sleeping and current consumption. <a href="http://forum.arduino.cc/index.php?topic=78430.0" rel="nofollow">http://forum.arduino.cc/index.php?topic=78430.0</a></p>

<p>Maybe explain what you are doing (what size battery you have) and we can add some advice about ways to save power </p>
 6740: <p>That depends very much on how delay() was written (and how it will be written in the future!). There are "sleep modes", which will reduce the power consumption of the arduino - these are one of the best way to reduce power consumption. Delay() may or may not activate these. If not, there could be a replacement Delay() function that could do this.</p>

<p>If you want to reduce power, check out <a href="http://www.gammon.com.au/power" rel="nofollow">http://www.gammon.com.au/power</a> - this is an excellent step-by-step tutorial on how to reduce power consumption from 50mA down to 288 µA</p>
