As Chicken Week here at Pi Towers draws to a close, we are all thinking deep thoughts about roasting temperatures and the very best fillings for omelettes.

The eggs Dennis Hejselbak is working with are not for omelettes.

Dennis, who lives in Denmark, has built a Raspberry Pi-powered incubator, complete with camera. Chicken eggs take about 21 days to hatch, and today is day 11 of the incubation period, so if you keep an eye on the stream on his eggs page, you should be able to watch them hatch in ten days’ time.

When you’re hatching eggs, there are a few variables you’ll need to keep an eye on. There’s heat, which in this incubator is controlled by a light bulb (the box is polystyrene, so it’s well insulated) and an old CPU fan. Dennis needs to make sure the box is humid enough – that’s what the sponges are doing in the picture above, while a hygrometer attached to the Pi checks for humidity levels – and he turns the eggs manually two or three times a day, which is vital for a successful hatch. (He says that he’s hoping to automate the turning for the next batch of eggs he raises in this incubator.) Temperatures and humidity are captured on the live stream (this is a static image: click on the picture for the real stream on Dennis’ website).

Why would you build your own incubator? It’s much cheaper than commercial alternatives; you can add features like that camera; and the satisfaction you get out of building something like this yourself is enormous. This project is well within the grasp of schools: Dennis has made complete build instructions, with all the Python code and wiring schematics you’ll need available. (If you do start an incubator at school, make sure someone has access to the classroom at weekends to turn the eggs three times a day if you haven’t automated turning; chickens do not stop incubating outside school hours.)

Frankly, I’d rather like to start a chicken incubator at Pi Towers, but Emma has already forbidden office dogs, hamsters and anything more highly evolved than brine shrimp, so I’m guessing we may be out of luck.

This marks the end of Chicken Week.