Wall Warts

I forget where I read that neologism. It refers to the transformers which convert high voltage AC to low voltage DC for example for this computer. If they are plugged in, they consume electricity, even if they are not in use. Obama says unplug them

"Using compact fluorescent light bulbs, energy efficient appliances, and unplugging power chargers when they're not in use are relatively simple solutions, he said."

But wait, why don't they unplug themselves ? About 15 years ago, I was watching Italian TV and there was a report on the invention of the year award. It went to the guy who invented the wall wart which disconnects itself from the AC current when no DC is demanded from it. Why isn't this invention used ?

This is a very simple idea. I see no problem with a mechanism to measure the flow of DC out of the wall wart and flip a switch inside the wall wart interrupting the wire which connects the wall wart to the wall when that flow is very low. I am fairly sure that this works, even if the appliance powered by the wall wart has a battery in it. Once the battery is fully charged, current can't flow through it in the charge me more direction.



My reaction was "why didn't I think of that ?" Now my reaction is "why the hell aren't all transformers self disconnecting ?"

Now it is clear that wall wart energy consumption is just not on my mind when I am shopping for a laptop (battery life maybe but once it's plugged in I have no concern I confess). I think that, as with compact fluorescent light bulbs, this is an area in which government intervention is reasonable. Consumers just aren't paying attention, so a law requiring newly sold wall warts to be self disconnecting seems to me to be a good idea.