I am trying to use these as the one and only heat source. Problem is, i have not come across one that is above 100 watts. I use them in the house with the baby chicks becuase they actually sleep at night this way. They are pretty expensive too. I have a total of two of them and the one has lasted for YEARS.
I am so paranoid that the light bulbs will blow on a cold night. I do not heat the house above 70 degrees and the heat source has to be reliable.
I do find them a safe and reliable method of taking care of my babies. I only have 4 chicks left in the house now. They are with the parrots in the bird room. The rest are out in the nursery and I have the white heat lamps on them. I am afraid of the infrared heat lamps, i have been told by quite a few people that these are bad for the developing eyes on chickens less than 8 weeks old.