So Thomas Edison. Yes he purposely electrocuted an elephant to make AC power look unsafe. But he was also an early pioneer in lightbulbs, most famously, the edison-type bulb. You probably have a bunch of A19/E26 bulbs kicking around your house, even if they have been converted to compact fluorescent or LED to reduce power.
Now, an earlier popular method of reducing power was the dimmer. A dimmer works in a fairly simple fashion. Your power is AC (despite the fate of that poor elephant). This means that between 50 and 60 times per second it goes from positive to negative, crossing through zero-volts. What a dimmer does is take this sin-wave (left), and just delays the turn-on time by a little bit (right). This has the affect of causing there to be less power delivered, and, in a resistive edison-style bulb, less light.
So what happens is, you and I have gone out to the hardware store, and bought dimmer-switches and retrofitted our homes over the past 30 years. And then the CFL / LED lights came on the market. And this caused trouble. The early ones of these low-power lights didn't support dimmers at all (you could either remove the dimmer, or just accept a lowered life-span of the device and some buzz/flicker). You see, the CFL has complex voltage supply needs (generally higher than your household AC). This means it has a mini power supply in the bulb in the base. And it just doesn't like the delayed start.
Eventually dimmable CFL came on the market, but were quickly eclipsed by cheaper, simpler, better LED lights.
Now the LED light faces the same challenge. Your retrofit dimmer mucks with its power supply, either achieving nothing, or breaking it. But, in the same fashion, they gradually came out with dimmable LED bulbs (the power supply tracks the zero cross offset and reduces its DC output).
OK. So back to me. When I moved into this house (2004) I made some changes to the lighting. One of these was changing out the large brass chandelier with a different one. And it takes 15 x 100W bulbs. 1500W yes. So to offset the power this used, I installed a dimmer of course. And it was a bit complex because it had a 3-way switch (top and bottom of stairs). So I found a high-power 3-way capable dimmer, and was happy. When CFL started to get popular a year or so later, they didn't support dimming. I always said to myself, when the first bulb in that burns out, I will go back and look at it.
Fast forward to 2017. 0. None. Nada. All of the bulbs from 2004 are still in happy operation. You see, that dimmer extends their life. So I start looking. One approach, I can find an automatable 1500W in-wall dimmer. Nope, that is not a thing, seems like very few people have a single light fixture of this power, and those that do, want to use it for tanning 🙂 So approach two, reduce its power. So I ordered 18 x 15W LED (dimmable, you have to check) bulbs. And after some precarious bulb exchange, you can see the result in the upper left photo. A big pile of old edison bulbs. Now my thinking in getting the 15W bulbs is they are '120W like in light output' as a marketing term. So I assumed they overstated that a bit (1600lm each, but i don't have an accurate lumen meter to check). So since I have a dimmer on this, better to be able to go a bit more light than needed right?
Now, I could have gone with smart bulbs. 15 of them, and then had individually addressable lights in this chandelier and a fancy wall panel to operate. But, well, that seems a bit over the top. How often have you said "I want the 3 o'clock bulb in the 2nd - row of that chandelier just a bit dimmer?".
So now that the power is reduced (from 15x100 @ peak to 15x15 @peak, e.g. from 1500 to 225W) we can move ahead with a more rationale automation strategy. And I'm going to continue with the zigbee dimmer from the earlier post. It allows for an 'add-a-switch', e.g. a GE 12723. So i head on over to amazon to order it, and, what, has amazon got me figured out now? Its available as a monthly subscription? I need so many of these they are offering me to just have them show up monthly? ??? Nice try mr bezos, but, well, its the same price for one vs subscription, I think maybe I won't lock in just yet.