Need help on estimating power consumption

wvmarle:
How can you know at which position the stepper is upon startup? Or what if the stepper misses some steps occasionally?

I want to position the door myself in the closed position when i start the arduino for the first time. Its the easiest position to start from and replicate everytime i would change something

You may consider using a servo...

I just don't see how i could fully open or close a door with a servo unless i make a huge lever...? am i missing something here, bacause a huge lever would result in much more force needed to be used.
I'm still trying to figure out how to handle missed stepper-steps. i was just hoping that those could be avoided or minimized with a decent setup.

A counterweight (or spring) on the door is also a good idea

thats a good sugestion indeed. adding counterweights shouldn't be too hard.

jremington:
This is an idiotic requirement:

could you explain why? I have some LG HE4 18650 batteries that are capable of 20+A drain, and the capacity of a 18650 should also be sufficient. where do you see the problem of using a single 18650?

and i'm asking this because before measuring because i'm still building the coop, and would like to order all parts so that i don't have to wait for it later. i'm simply not able to build the complete setup at this point to test and measure.