Reptile light bulbs are 25 watts to 60 watts (use less energy) and cost less. Not sure if anybody has tried them
Because I was brooding outdoors in a central NC summer (night temps no lower than 68), I used reptile night bulbs at 100 and 60 watts (stepping down to a 40 watt regular bulb as the chicks grew and the nights stayed in the low 70's). I used these bulbs in a regular heat lamp and it was quite successful for this circumstance.