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.
Wireless Joystick Hookup Guide
A hookup guide for the SparkFun Wireless Joystick Kit.
IoT Power Relay
Using the ESP32 to make a web-configured timed relay.
ATX Power Connector (4-Pin) Breakout Hookup Guide
Do you need to power a project with 12V and 5V from one wall adapter? The ATX power connector breaks out the standard 4-pin computer peripheral port for your 12V and 5V devices!