As a heat source, the actual wattage of a bulb is what determines how much heat is produced. So a 13 watt CFL (Compact Florescent Lamp - the "spirally" ones) produced only 1/3 a much heat as a 40 watt incandescent bulb. It may say it's equivalent to a 60 watt, but that is light output, not heat. For an incubator, the "waste heat" that the CFL don't produce is what make the eggs warm.My bf wants to know if it is ok to use the energy saving bulbs, the ones that are all spirally??
If you use a CFL, it is likely you will need several of them to get the heat right and that really defeats the purpose of them.