add power usage blurb

Author: Max Roby

docs/12-self-hosting/01-overview.mdx

@@ -25,12 +25,21 @@ There are many ways to self-host CI/CD runners, and which one is best for you wi
 own situation and constraints. For the purpose of this guide we will make the following assumptions:
 
 - 💻 User already has their own hardware
-- 💸 Budget is $0
+- 💸 Budget for new hardware, software, or services is $0
 - 🛠️ FOSS tools should be prioritized where possible
 - 📜 We define `Self-Hosting` in this context to refer to a user taking responsibility for the
   operating-system level configuration and life-cycle-management of a given compute resource (metal,
   on-prem, cloud VM, VPS etc...)
 
+## Power Consumption
+
+Hosting your own runners also comes with an increase in power consumption. This will vary based on
+the hardware you use and the prices of energy in your area. Below are some useful resources for
+discovering the potential energy costs of self-hosting.
+
+- https://outervision.com/power-supply-calculator
+- https://energyusecalculator.com/electricity_computer.htm
+
 ## Requirements
 
 This guide is tested on devices which meet the following requirements: