We dry some of our clothes inside, and some in the dryer.
Socks, underwear, kids' shirts, bedsheets, etc. we dry in the dryer. We have a gas dryer - I went a month without using it and a month with using it and the difference was negligible for what we use it for.
The rest we dry in our basement (fall-mid spring) or outside (late spring-summer). We have a dehumidifier in our basement, so with that going everything dries overnight for the most part.
If you're worried about mold, the best thing you can do is make sure everything dries evenly. I'll rotate, flip, and resituate laundry if there's a lot or it's taking a while to dry, just so that all of the damp sides get exposed to dry air at some point.