Use energy-efficient light bulbs if you're looking to cut as much energy costs as possible. The brightness in this bulb amounts to 1 200 lumen.
From Amazon
Osram DULUX D 18W/830 G24d2 (100W) FS1 153 mm compact LLp warm tone for CCG, 1 piece [Energy Class G] [Energy Class G]
LED Bulbs
Osram 18W Dulux CFL D 2 PIN Warm White - OS025704
Big on Electricals
Osram 18W Dulux CFL D 2 PIN Warm White - OS025704