Solar-powered smartwatches might become more practical in the years ahead. Researchers have developed a flexible solar cell that could be an ideal fit for future wearable tech. It’s 10 times thinner (0.3 micrometers) than human hair and, as you’ve likely noticed in the photo, light enough that it can sit on a flower. And importantly, it’s still reasonably powerful with an output of 9.9W per gram — it might have enough power for a full-featured smartwatch.

The technology could keep devices running for a long time, too. Tests suggest that it could degrade by just 4.8 percent after more than 4,700 hours, and last for 20,000 hours with “minimal degradation.” The useful shelf life would be about 11.5 years, Monash said.