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.
Blynk Board Project Guide
A series of Blynk projects you can set up on the Blynk Board without ever re-programming it.
IoT Power Relay
Using the ESP32 to make a web-configured timed relay.
Nuclear Battery Assembly Guide
How to put together your BYOT (Bring Your Own Tritium) Nuclear Battery Kit!
LuMini Ring Hookup Guide
The LuMini Rings (APA102-2020) are the highest resolution LED rings available.