If you’re worried about your loved ones missing their next appointment because the battery in their watch ran down, consider giving them a watch that never needs a new battery—or winding. For years now, watchmakers like Citizen, Casio, Seiko and Timex have offered watches with photovoltaics integrated into the watch face. Such watches start at about $20 online these days.

The great thing about these is, you don’t have to look like an ecogeek or solar-geek when you walk around with one on. And with some, you can’t even tell that there’s a solar panel on them, like the Citizen Calibre 8700 (Pictured). It’s a great way to tell time and a great little way to support solar power.

Pictured: The Citizen Eco-Drive 8700, courtesy of Amazon.