Ask HN: On-Demand Phone Charger
Not to nitpick, but surely there is a charger out there in the marketplace that can apply electrical load once the iPhone/Android gets connected to the charger. That is assuming that Energy Saving Trust accurately assert that it is eating electric cost wether the device is connected or not. [1]
Perhaps with a big zenier diode or something instead of an always-on wounded transformer coil sucking electricity …
Is there such a thing? I could imagine some type of mechanical (or even electronic) relay to kick in that coiled transformer load but as a tiny consumer product?
Does one exist? If so, how would one search for such a product on search engines?
Napkin Math:
35W/hour (rated phone charger)
24 hours x 365 days (always on)
306.6kW/year, total usage (1 charger)
$0.149/kWh electric rate
$45.68 per charger
or $274.10 annual electric bill for six(6j chargers
of course, Energy Saving Trust claims the chargers are essentially always on, whether you have the device connected or not.
[1] http://monopolybuysellrent.co.uk/advice/energy-saving-tips/