What is an energy saver?
Although there come in all kinds and colours, they are usually small devices that include their own plug. They resemble a mobile charger, although they are usually somewhat larger and more colourful. They are also usually cheap: The best-selling models range from 5 to 35 euro.
But we insist: Behind this generic concept there is a little bit of everything.
What energy savers marketed by different brands have in common are their two main hooks:
1. They could not be simpler to install: Just plug them in
2. They promise savings on your electricity bill
Given this information, the success they enjoy with a large part of the population is obvious. But, is what they promise actually a reality?
How does an energy saver work?
An energy saver is a device that claims to use the latest technology to eliminate excess energy generated by power peaks produced by some appliances.
This excess or residual energy is the so-called reactive energy. Unlike active energy, it cannot be consumed and it is of no use to you at all. It is generated in appliances that have motors (fridges, washing machines, dishwashers, etc.).
Its external appearance does not indicate that we are dealing with a particularly complex gadget and, indeed, an energy saver is fundamentally a capacitor.
Without going into technical details, what this capacitor does is capture the residual energy and redistribute it within the system in such a way that it is actually consumed (active energy). That is, they minimise reactive energy and voltage rises.