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
LiPo Charger Plus Hookup Guide
This tutorial shows you how to hook up and use the SparkFun LiPo Charger Plus board.
SparkFun Qwiic Quad Solid State Relay Kit Hookup Guide
A Hookup Guide to get you started with the SparkFun Qwiic Quad Solid State Relay Kit (say that five times fast!).
How to Run a 5V Device On a 3.3V System With Qwiic
Power up your 5V I2C devices on the Qwiic system! This tutorial shows you how to use the SparkFun Qwiic 5V Boost to integrate power-hungry sensors like the SEN55 seamlessly.