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.
Beefcake Relay Control Hookup Guide
This is a guide for assembling and basic use of the Beefcake Relay Control board
IoT Power Relay
Using the ESP32 to make a web-configured timed relay.
Buck-Boost Hookup Guide
This tutorial shows you how to hook up and use the SparkFun Buck-Boost board.
Hookup Guide for the SparkFun RedBoard Artemis
Get started with the RedBoard Artemis - all the functionality of the SparkFun Artemis module wrapped in the familiar Uno R3 footprint