Expects not only an increase in temperature.
Leaving the charge overnight in the outlet, you can not be afraid of ruin. It won’t affect your electricity bills. If nothing is connected to the charger, there is no consumer of electricity and there is nothing to “suck” energy.
If the charger is left in the socket at least for the night, at least for life, the maximum that will happen is to heat up a little. Told regarding it Maxim Dvoryashinrepair technician.
On the contrary, it is best not to get it at all. Otherwise, you can loosen the socket or bend the plug of the charger. Especially for the portalMorning News» Dvoryashin spoke regarding the zero impact of charging on the payment amount:
A plug left in a socket without a device consumes no electricity, as there is no source for consuming that electricity. Therefore, you should not worry, it does not affect energy consumption in any way.