I use a MarsHydro FC-4800, so I got some figures from the net, about running costs from Europe.
Thailand electric is 3-4THB/unit but then figures i was getting seemed a bit low bearing In mind I was told to budget 2000thb/month per light.
Here's my working anyways.
Light Monthly Cost 0.3 euros/unit = 11THB/unit (European Tariff)
18H - (50% Power Max, Seedlings & Vegetative) 480W=0.48kw/h
1 day Wattage: 0.48kw/h x 18 hours= 8.64kw/h
Daily Cost: 8.64kw/h x €0.3/ kw/h= €2.60
Monthly Cost: €2.60 x 30 = €78.00 = 2870.06THB (100%)
50% of 2870.06THB = 1435.03THB
12H - (100% Power - Flowering) 480W=0.48kw/h
1 day Wattage: 0.48kw/h x 12 hours= 5.76kw/h
Daily Cost: 5.76kw/h x €0.3/ kw/h= €1.73
Monthly Cost: €1.73 x 30 = €51.84 = 1907.56THB