Wow, that works great. Now you can have an automatic "charging" station for that balloon powered car you designed: https://www.youtube.com/watch?v=wkyOi47r9Io
Use of the silicone baking mold is brilliant. At first I thought that was a 3D-printed part (made me wonder about durability) but this a great source for it and smart to start with and design the structure around.
Were those TPU flap valves printed in place? Almost looks like they were.