This is a plugin for Cura (versions 15.06 and up) that adds an extra window that shows the print cost based on the fillament used estimation combined with the density and price, which can be set by the user. It also includes Electrical cost.
To use the plugin, you simply download all the files and put them in their own folder inside the plugin folder of Cura:
/plugins/ElectricPrintCostCalculator/