i mean cellphone chargers when not used and kept plugged in.
Yes, they will consume a small amount of electricity. Most cellphone chargers are switching power supplies and use much less energy when idle than do the old transformer style chargers. You can generally tell whether your charger or other plug-in AC adaptor is a transformer or the more efficient switching power supply simply by picking it up. The transformers will be much heavier. You can also do a crude judge of how much energy is being wasted by simply feeling the charger since all of the power loss shows up as heat being given off by the unit. Notice that the switching power supply chargers will be cool to the touch while the transformer based chargers and AC adaptors will feel warm.
very little, and the is no risk of fire hazard with good power supplies if they are not smothered
Dear pa, Thank you, am also fine like you then dear am one 18years experienced power electronics engineer from that if a good working charger will not consume electricity.
Cellphone chargers, yes, if it is not switched off at the wall. Extension cable, no. If it has an indicator light it will use a very tiny amount.
Not if they aren't switched on! You should never leave a cellphone charger energised. Although power usage is very small, the risk is fire. If by extensions you mean the cellphone charging lead, it can't use power if it's not in use, i.e. connected to the 'phone. When connected, there will always be a tiny power loss as heat.
