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by post_break 3638 days ago
I love my Wifi lifx bulbs. Amazing output, low latency, and the standby usage is 0.7w when off. My biggest complaint is there is no physical switch to turn them on and off. Using my phone is slower than a switch, and if I switch them off they won't be able to come back on with my phone or IFTTT schedule. 0.7w seems low to me for standby.
3 comments

According to this [1], an iPhone 4 only uses 0.024W on networked standby. So 0.7W per bulb is not really low.

Even worse, it's above the EU limit which mandates <0.5W (since 2013) [2].

[1] https://www.iea.org/media/workshops/2012/network/3ViegandSes...

[2] https://en.wikipedia.org/wiki/EC_Regulation_No._1275/2008

"0.7w seems low to me for standby."

Affordable for many, yes, but IMO, for a LED lightbulb, that's horrendous. Let's do the math: 0.7W full time is 16,8 Wh a day.

In use, a 1000 lumen bright LED bulb uses 14W. If we assume you have it switched on 12 hours a day, that 0.7W at 24 hours a day adds 10% to its power usage.

More realistically, your LED bulb will take 10W, and be on for four hours a day, for 40Wh. That means that 16,8Wh adds almost 50% to your power usage.

And I think the typical bulb will use even less power and an even lower duty cycle. 8W, 2 hours a day, and you have a radio broadcaster that occasionally switches on a light :-)

By the way, 0.7W also is also against the spirit of an EU directive on power consumption (http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:320...), which by now (it's over four years after this came into force) states:

The power consumption of equipment in any condition providing only a reactivation function, or providing only a reactivation function and a mere indication of enabled reactivation function, shall not exceed 0,50 W.

What if wall switches were replaced by very simple phones...or even watches. It would effectively be running the one app all of the time, defaulted to the lights in the room. There could even be some sort of hard-wire bus between this switch and the bulbs, to communicate through RF interference.
With the drastic price fall of Android tablets (mostly the Amazon Fire) - there have been a few enterprising people that have hacked them into basically being "smart switches" for their homes.

The results are still a little too janky for my taste but the costs are getting there.

Or just use something like the Philips Hue Tap [1], which sends an RF signal (ZigBee) solely using the energy from your button press (no batteries).

[1] http://www2.meethue.com/en-us/productdetail/philips-hue-tap-...

I wish this would work with LIFX. I refuse to go to Hue but man I want a physical switch.
Since touch screen tend to break and are expensive to replace, I suggest that we instead use a simple button interface. I'm sure you could find some kind of USB button that you can hook up to the phone on your wall.
Zigbee hardware switch: $36 https://www.amazon.com/GE12722-Z-Wave-Wireless-Lighting-Cont... 7 inch touchscreen android tablet: $39 https://www.amazon.com/gp/product/B01CGSWYFM/

The zigbee switch also has a relay in it, which is the majority of the cost, but if you're controlling a bulb with a built-in receiver, you're not using that relay. There really aren't much cheaper zigbee, zwave, wifi or bluetooth wall switches.

This is what I do. I use my old android phones, on a dedicated network.

I'm also building a RPI kiosk to manage them