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.
Alternating Current (AC) vs. Direct Current (DC)
Learn the differences between AC and DC, the history, different ways to generate AC and DC, and examples of applications.
IoT Power Relay
Using the ESP32 to make a web-configured timed relay.
Qwiic Quad Relay Hookup Guide
SparkFun’s Qwiic Quad Relay is a product designed for switching not one but four high powered devices from your Arduino or other low powered microcontroller using I2C.
Single Cell LiPo Battery Care
This tutorial will go over how to safely charge, connect, disconnect, reinforcing the cables, and handle single cell LiPo batteries.