Reducing Arduino Power Consumption
Contributors:
Alex the Giant
Alex the Giant 
Resources and Going Further
More information on low-power modes and options can be found in the datasheet for the 328P.
For more power-related fun, check out the following SparkFun tutorials.
Electric Power
An overview of electric power, the rate of energy transfer. We'll talk definition of power, watts, equations, and power ratings. 1.21 gigawatts of tutorial fun!
Benchtop Power Board Kit Hookup Guide
Need more power? This Benchtop ATX Power Supply Kit should help give you the boost you need to power those energy hungry projects.
Adding a Timed Button to a Project
This tutorial will walk you through making a timed power controller for interactive projects. You will learn how to add an on button that will provide power to your project for an amount of time and then turn off again.
Understanding Thermal Resistance
Discussing what thermal resistance is, how it’s used for thermal management, and how to maximize the life of your project.