150 Mhs gets you roughly 3 USD per day, electricity cost = 0,1 USD/kwh , 0,75 ( 750 watt ) x 24 x 0,1 = 1,8 USD electricity cost , 3-1,8= 1,2 USD profit. Is it sensible to build a mining rig with this conditions? Maybe with second hand parts, definetaly not with brand new equipment. Is it sensible to continiue mining with your existing rig? Yes
This is what I figured it would cost.
But if he is spending a higher amount in electricity then it is certainly not worth it even if ethereum price doubled in price to it's all time high.
Some places even charge a different rate at night time so all these factors are involved to even have a mining rig running to turn a profit.