The Content Of The Article:

Hello, I wish that finally, my question gets answer, it is the 5th time that I write to you. I read on the internet that there is an electricity saver up to 48% (video demonstration with a fridge) One economizer per home, connected to one of the sockets (max power 19kva, single phase 220V) Price of the unit: 59,90 € The house is heated by a heat pump with a 30 cm roof insulation Hoping that my email will be read and you can answer it. Thank you in advance

The laws of physics are stubborn. One watt consumed = 1 watt restored. I do not see how a device, whatever it is, would allow to escape this fundamental rule enacted by a certain Blaise Pascal. You mention the quality of the insulation of the house: it may be a factor limiting the consumption of a possible electric heating.
As indicated in one of my answers, although anxious to respect my commitment to answer a maximum of questions, it is not possible for me to satisfy them all...

On the same topic

  • Questions answers
    • Cable section between branch circuit breaker and switchboard
  • DIY tips
    • Automation of a blind: energy savings

This may interest you

Video Instruction: Chinese Power Saver - Does it actually save power?