Are you sure 3 x 1060 3GB consumes just 10 Watts per day? DId you calculate entire pc power too?
This page says a pc with a single 1060 FE consumes around 200 W
Lets say the card only takes 100 W, so 3 of these cards = 300W + 100W of pc = 400W total. Thats 400W total load per second per hour x 24 hrs. In one hour your pc has already taken 0.8 - 1KWhr.
Your bill is Rs 5 per unit of 1 KWhr I suppose. So in 24 hrs you will get ~ 24 KWHr = 24 x 5 = Rs 120 per day. 120 x 30 days = 3600 if the price per unit does not change like my power company does.
Your rig consumes approx 720 units a month.
I only have option of MSEDC (biggest power supply cheater company in Maharashtra & India).
My electric bill is 6.73 for 101 -300 units, 9.70 for 301-500 units, 11.20 for 501-1000, and Rs 12.48 for 1001+ units. And for us 1 unit = 500W and not 1KW like other areas in India.
So if i have you exact rig and my units double (720x2 = 1440 units) I will have to shell out 1440 x 12.48 = Rs 17971 per month. This is not including tax etc. Not affordable for me.