Or you can use a combined UV/heat bulb like this, 100w or 160w depending on the size of your enclosure. Make sure you have a light fixture with a ceramic base that can handle the wattage (they often sell these at Home Depot/Lowe's or hardware stores for less than pet stores). http://www.google.com/products/cata...=X&ei=QtSST-CSMtDUiAKu3szkDw&ved=0CIUBEPMCMAE
UVB tube lights are low energy. they do not emit heat like a standard bulb, spotlight or combined MVB lamp.
The electrical cost can easily be calculated. Find out what you pay for electricity for a kWh (kiloWatt hour)... it will say on your electricity bill.
A kiloWatt is 1000W, so 1kWH is how much you pay for using 1000W in an hour.
Cost of running bulb for day = Bulb Wattage / 1000 * kWH unit cost * number of hours it's switched on.
If you have separates:
A 150W basking bulb on for 14 hours with electricity costing 15 pence a unit works out at: 150/1000*15*14 = 31.5 pence a day.
A UVB tube of 20W (these are low energy), also on for 14 hours works out at: 20/1000*15*14 = 4.2 pence per day.
You would need both of these
An MVB combined bulb will save you having two lamps, but will run at the higher basking bulb cost... saving you 4.2p a day.