Recently, I wanted to delete a Power Plan on Windows 7.
First of all, you cannot delete system Power Plans (Balanced, High Performance, and Power Saver). You can only delete power plans that you have created.
Go to Power Options in your Control Panel.
I had created a Power Plan called "Mahesh". See below. I want to delete this.
Click on "Change plan settings" next to the plan name.
You will go to the following screen where you will see "Delete this plan" option at the bottom left corner. Click it to delete the plan.