Hey guys,
i just bought some hue none color (white) bulbs and i want to measure the power they use to send to emoncms. The thing is i have no way to measure the power BUT I do have a wemo insight so i can read the power the hue light bulb is using through a simple light that hook up to a wall socket. I’ve noticed already the the colored bulbs i have that they use less power if the brighness is lower or if the color changes. Now since the white once don’t use color i wonder if i measure the power at say 5% 10% 15% … 100% brightness … if i get some kind of fixed constant multiplier to measure the power based on the brighness setting of the bulb. if this is the case i can make an automation in home assistant to read the lights brightness and calculate its power using that fixed constant and brightness level and then send it to emoncms every 5 seconds using input api + curl. But i’m not sure if there would be such fixed constant relative to brightness and before spending time on it to see if there is, i’d thought i’d ask here. i think it might work for the white only ones but not sure for the colored ones. The home assistant part is not an issue as i’m currenly already sending 4.5 watt value to emoncms when they are on and 0 when they are off. but this is probably not always correct. Hence the idea / question i had …
can answer it myselve now as i took the measurements using a wemo insight, a plain light fixture and one of my hue white bulbs
There isn’t a constant magic value to calculate it, there is a correlation between brightness and power usage although it’s not linear at higher brightness it uses more power.
So what i did was measure the power values at 10 - 20 - 30 - 40 - 50 - 60 - 70 … 230 - 240 -250 brighrness setting, look at the values and write it in a table. Then i wrote a (personal) component for home assistant that checks brightness every 5 seconds the brightness level of my hue white bulbs based on that brightness level and the measurements i have now in my table i can calculate an estimated power use, that estimated power use i send to emoncms now and use it to add to my other readings of power. When the bulb is off it uses 0.3 W at around 250 - 255 (highest brigness level) it uses around 9 W. When i compared my estimated values send to emoncms to the values measured by my wemo insight now (which i also see in emoncms) they give a good estimate on the power use without measuring it for real. There are some slight deviations but it works fairly well for estimates when i compare the 2 value so now i can know my hue white bulbs power use without actually measuring it in real time but using estimates.
Too bad i can’t think of a way to the same for colored hue bulbs as there are more settings then just brightness level… so what i do with them is send the value that i measured at a the light setting i use the most to emoncms not as accurate as for my hue white light bulbs but it’s better than sending nothing all 
edit: here’s the measuments i had taken at diffrent brightness levels:(it’s good to know that brightness level 0 is diffrent from the bulb being off, when i had set brightness level 0 the light was still on but very low brightness, it’s not the same as turning the bulb off)
