If you let your hair air dry, it should produce diffuser like results, if not better!
For me, using the diffuser produces the same results as letting my hair dry overnight while I sleep with my hair in a bun. If I just let my hair air dry naturally, sure it takes like 3 hours to dry completely, but the results are even better than diffusing it!
All of these options give me great hair results though! So you'll be fine without the electricity. Just remember not to touch it too much while it dries. The more you touch it, the frizzier it'll get. Once it's completely dry, feel free to shake your hair and ruffle it up with your hands to add volume.