AC light or fan timer with 0 WATT standby power
To find this or similar module just look for keywords some of these keywords: AC, timer, delay, relay, countdown. I got this with shipping for less than $3 a piece.
Very important thing it that both the timer AND the relay is rated for AC voltage of your country and relay is powerful enough to drive your load. They are usually rated 10A with is so much that it can drive an average electric kettle that runs at 230V, but always check first to make sure. For stuff like for example 30W fans/lights it only needs 30W/120V=0.25A for US/JP and 30W/220A=~0.13A for 230V countries, so 10A is amply rated.