Intel(R) Power Gadget is a program designed for computers with Intel processors for helping you monitor power usage. The application provides you with real-time data, allows you to keep a log containing the offered information, and comes without a price.
As soon as you launch the utility on your Mac, it immediately starts displaying information regarding your computer's power usage. If you want to save the offered information, simply go to the app's main menu -> Logging and select the "Log To File" option. To stop recording content, click the aforementioned button again. The program will immediately generate a CSV file that contains the offered power usage information.
Another advantage is that the application uses a very small amount of CPU resources while monitoring your power usage.
The only thing I'd add to this program would be a built-in help manual. A guide might come in handy to beginner computer users who aren't familiar with the type of details this application has to offer.
Still, the utility proves to be a reliable solution for monitoring real-time power usage on your Mac. It's efficient, simple to handle, and free. You should definitely give it a try.