Drying by the light of a window indoors is not that effective. Outdoor drying is effective because of a combination of the direct sunlight and air circulation. Cloth diapers hold a lot of moisture even after running thru the spin cycle, so if you were drying indoors, you’d probably want to run a fan too which will drive up you electric bill too.

But if the window is visible to the outdoors, your apartment management may say diapers in the windows are unsightly too.

I’d just go with the electric dryer because you’re gonna have your hands full with so much more because of your precious newborn

Buy yourself one of those expaning wood racks for drying clothes and put it near the window where the sun can get to the diapers. It will work just fine, the only difference is you won’t have the outdoor breeze blowing through them to help dry them, but you will benefit from the natural anti-bacterial properties as well as the natural bleaching properties of the sun.

Congratulations for using cloth diapers, it is something I wish every mother would do for their children. I’ve always thought that it was the child’s health and wellbeing that should come first, not convenience.

Good luck.

Throw them in the drier.

that would be fine