Ways to generate heat and contains that heat safely

I’m building an egg incubator. I have an “unlimited” supply of fertilized eggs, hence I want to try a few approaches.

Can you help me scientifically choose the kind of container, especially its material, and heating source that I could use to maintain a constant, and uniform temperature of approx. 38 degrees Celsius inside that enclosed space, and an hygrometry of 50% to 70%. The incubator itself would be inside a regular house which temperature is already apprx. 20C . I’m open to any solution, especially if it involves scavenging electronics.
I don’t need light, I just need heat. Right now I’m using a PP plastic box with two halogen bulbs inside, but I don’t like it from a security point of view, because the melting point of PP is too low and the bulbs too close to the box.

Power resistors on a sheet of aluminium would dissipate the heat. If your current lamps provide sufficient heat, that would be a good starting point for the power required. Use a number of aluminium clad power resistors of the correct R and power rating.

Use a temperature sensor in the air space to monitor the temperature. Simply turn the power onto the Rs if too cool and turn it off when warm enough.

Use a humidity sensor to control humidity.

Weedpharma

in an enclosed and insulated box, you do not need much heat. the more insulation, the less loss of heat and the less heat needed inside.

you could use a hair dryer, an SSR and use a second SSR to control fan speed. wal-mart, about $10,00 for a cheap hair drywer with two stages of heat, internal thermal protection, and a fan with multiple speeds.
computer fan of 12VDC could be uses for more speed control.

thermal mass is also a consideration. if you put in a water bottle and an aquarium heater, it will maintain a temperature within a range. you could blow off heat from that to add more heat.
the idea with the hot water is that you cannot get it too hot and the amount of heat will require long ramp times, making control easier.

but, it would not recover quickly from large heat losses such as opening a door and letting all the heat out.

Light bulbs and heat lamps are often used in incubators. Go small so the chicks don't overheat.

zoomkat:
Light bulbs and heat lamps are often used in incubators. Go small so the chicks don't overheat.

Antoino:
I don't need light, I just need heat. Right now I'm using a PP plastic box with two halogen bulbs inside, but I don't like it from a security point of view, because the melting point of PP is too low and the bulbs too close to the box.

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