Lowest power consumption while designing 220v switch

Using Arduino General Electronics
1

I need to design a circuit that switches a 220v lamp(Lamp is about 10W-20W) by microcontroller with possible lowest power consuption. I have found minimal power consuption on triac and optocoupler circuit, it draws around 2.5 mA. Is there a more efficient solution ?

Thanks in advance

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it draws around 2.5 mA. Is there a more efficient solution ?

I doubt you're going to beat that. You need isolation and an LED (opto-isolator) is a fairly efficient solution.

You could build something that's "powered" from the 220VAC line so the controller only consumes power during turn-on & turn-off. i.e. That's how a regular wireless home-automation switch works. The controller remains idle when not sending commands and the batteries in my [u]X-10 transmitters[/u] last a long time.