Interesting....my last grow from seed to harvest, I tracked @ 6.7 cents / kwh and I came up with this for my entire grow.As I prepare for the first move from the paper towel to the Jiffy pods, I set up my tent with the proper lighting, temperature and RH. I did several environment tests over the last week using the room humidifier, portable A/C and the fogger to get temps and RH where I feel I can control them throughout the grow.
I'll keep the seedlings in the jiffy pods and in the dark until the cotyledons open. After they first show cotyledons, I'll turn on the lights but I want the lights low and temperatures below 80F (26.7C). I don't have to worry about the low temps here as it will always be above 72F (22C). RH will be higher than the shown 49% as the seedlings will be in a dome until I see some roots coming through the jiffy pods. I'll monitor inside the dome to keep RH around 70% to 75%. Once roots start to show they will be transplanted to the grow bags.
For the first part of the seedling stage I'll position the LEDs about 28 inches above the plant area and reduced the power to 84W (1/4 power). This gave me a Lux reading of 11000. The Demon light from @Budget LED allows me to adjust the light from 30W to the full 330Ws. I use a separate energy monitor for the lights so I can see exactly how much power I'm using. The lights are also monitored as part of the total power.
Until tonight.
$38.63 for electricity alone.