It is not just ambient electrical noise that contains usable energy. Others have demonstrated practical sensor energy harvesting from ambient WiFi and ambient b

It is not just ambient electrical noise that contains usable energy. Others have demonstrated practical sensor energy harvesting from ambient WiFi and ambient broadcast TV signals. I'd expect that the Sony device can probably use those too, so if you've got WiFi in your building you should be fine. If there is ambient radio, you can also use that for extremely low power data transmission from your sensors. The trick there is to not actually transmit any of your own energy. You instead either absorb or reflect the ambient radio. This is called backscatter communications. Here is a video showing a demonstration of both energy harvesting from ambient radio and backscatter data transmission [1]. If you use WiFi signals as your ambient radio for backscatter, the research group in that video has also demonstrated that you can make your backscatter data stream match standard WiFi protocols so that you can use ordinary WiFi equipment for the receiver. The above was fairly short range, but even so there are a lot of interesting applications. For instance you might want to have moisture sensors inside a wall to detect water leaks early. If your sensors are powered by ambient EM energy (noise or radio), you don't have to limit the sensors to places where you can easily reach them later to change batteries. They are fine if they are behind brick or drywall with no openings. [1] https://www.youtube.com/watch?v=gX9cbxLSOkE https://www.youtube.com/watch?v=gX9cbxLSOkE