How often have you been approached by a salesperson at your doorstep or got a text message on your mobile selling a device which can go in a wall and save energy or reduce your monthly electricity bill substantially? The so called “Power Saver Device“(known by different names) is nothing but Power Factor Correction (PFC) device that would connect to the mains and improve power factor measured by your electricity meter. However it is important to notice that utilities bills a residential user based on real power that does not factor in Power factor and thus none of these devices would really reduce your monthly bill. The so called “Power Saving” device may be useful for Industrial applications, where utilities charge the user based on PFC rather than real power.