All details can be found here : https://hackaday.io/project/189482-kokot-a-low-energy-chicken-coop-door

• Automatic chicken coop doors help to keep your chickens safe by working on sunrise and sunset hours to open and close.

• A chicken coop door is essential and its primary purpose is to provide safety for your chickens from predators.

• Kokot is an automatic chicken coop door which works with battery power and solar panel.

• It is designed to be as cheap as possible, fully automatic and will be a "low energy" device.

After a few brainstorming sessions we came to the following key specifications:

• the door should open/close phased with the sunrise and sunset hours. This seems to be better than classical light sensor. These sensors are prone to "false detection" in case of bad weather (false night) or when illuminated by car headlights (false daylight). 
• the system should be self powered (no mains into the fields)
• it should use a rechargeable battery and should be equiped with a solar panel
• the door should be "guillotine style" for compactness and efficiency (see picture above on right wall)
• the door should be automatic but should also offer manual "open close" capabilities
• the whole system should cost less than 40€

Optionnal specifications

• Kokot should be "smart". That is connected to internet and/or your smartphone 
• kokot should monitor temperature and humidity into the coop
• And of course kokot must be energy efficient to avoid draining the battery and to keep the costs as low as possible (smallest battery, smallest charger, smallest solar panel, smallest motor...)