A New Kind of Skeleton: When Solar Power Becomes Part of the Design

For much of watchmaking history, the skeleton dial has been a showcase for mechanical craft. Cut away the face, expose the gears, and let the wearer marvel at the tiny mechanical ballet keeping time. It is one of watchmaking's great traditions, and far from the only way to read the idea. MONDAINE, the family-owned Swiss brand, has asked a different question with its new Doppio Solar Skeleton: what if skeletonization could reveal solar technology instead? Here, the visible solar cell forms part of the movement itself.

The answer sits on the wrist. A precisely cut circular opening at the middle of the dial draws the eye past the hands, past the numerals, down to the solar cell itself, taking in light and turning it into energy. Instead of hiding it, MONDAINE makes it part of the design. Rarer still for that honesty to look this composed.

The Rise of the Light-Powered Watch

Solar timekeeping was once treated as a purely functional feature, valued for convenience rather than design. That reputation has aged badly, and buyers have noticed. Across the design-led end of the market, people now want objects that earn their keep without asking much in return, and a watch that powers itself from the light around it, natural or artificial, fits the brief almost too neatly.

The appeal is easy to grasp. The solar cell, integrated into the movement, gathers both natural and artificial light, feeding a rechargeable cell that keeps the hands moving through long stretches in the dark. There is no winding ritual to remember and, crucially, the solar system eliminates the need for regular battery replacements. The wearer simply lives their life, and the watch keeps pace.

That efficiency is only part of the story. MONDAINE makes the Doppio Solar Skeleton with cases and bracelets of up to 91 percent recycled stainless steel, and runs a free watch-recycling service at its Swiss headquarters for pieces that finally reach the end of the road.

Light Made Practical

The numbers behind the Doppio Solar Skeleton give the romance some spine. A few minutes of sunlight are enough to wake a fully discharged movement, and a single full charge carries the watch through as much as eight months in total darkness. Built-in protection against overcharging and deep discharge keeps the whole system honest over the long haul, so the watch asks almost nothing of its owner beyond the occasional glimpse of daylight.

MONDAINE is no newcomer here. It introduced what it calls the world's first analog solar wristwatch in 1973, which makes the Doppio Solar Skeleton the latest chapter in a solar story more than fifty years in the making.

Underneath sits a Swiss solar movement built on Ronda precision, pairing dependable quartz accuracy with a light-fed power reserve. The visible solar cell forms a functional part of the movement, bringing function and design together. Sustainability, told this way, reads less as a slogan than as a natural outcome. The Doppio Solar Skeleton is a natural extension of the Mondaine Group's long-standing sustainability philosophy. For more than 50 years, the company has embraced the principles of Reduce, Reuse, and Recycle. Since 2020, it has also achieved comprehensive carbon neutrality across Scope 1, 2, and 3 greenhouse gas emissions, independently measured in accordance with the GHG Protocol, while supporting certified reforestation projects to address remaining emissions. Its Swiss factory even runs largely on its own solar power, so the energy that charges the watches also helps build them.

Skeletonization, Turned Inside Out

Here, the Doppio Solar Skeleton makes its boldest move. The watches belong to MONDAINE's Doppio collection, whose design language leans on repetition and depth: double line hands and indexes, a concave dial, and a double-domed sapphire crystal that layers the face so the eye travels inward rather than skating across a flat surface. That approach sits within MONDAINE's wider design philosophy of clarity, functionality, and timeless Swiss design. That descending quality gives the new model its stage.

Where a traditional skeleton watch parts its dial to flaunt mechanical craft, the Doppio Solar Skeleton exposes its solar cell, a functional part of the movement that becomes part of the watch's visual identity. The circular aperture at the center of the dial echoes the line's concentric, repeating forms. Through it, the purple surface of the solar cell spreads beneath the hands like petals caught mid-bloom. The outer ring keeps its indexes for clean readability, the logo and solar markings are laser-engraved into the surface, and a vivid red seconds hand ticks over the lot. Instead of mechanical complexity, a functional element of the solar movement becomes the ornament. The exposed solar cell is not only practical. It becomes a design feature in its own right, giving the wearer something to notice and appreciate each time the watch catches the light.

The effect lands differently across the two versions. On the polished silver 316L steel case with its vegan grape leather strap, a plant-based material that has been animal-free since 2022, the purple reads deep and rich against the black dial, understated and easy. On the polished black case with its matching mesh bracelet, the whole thing turns moodier, almost architectural. A 41 mm case diameter and a discreet date window keep either one at home on a boardroom wrist or a weekend one, and a 5 ATM water-resistance rating comfortably handles everyday wear.

The Substance Behind the Statement

The two executions do more than offer a choice of color; they let the watch read the room, and a quick-release strap lets it move from a desk to a dinner in seconds.

Seen together, the credentials are not gestures. A carbon-neutral maker, more than fifty years of solar know-how, recycled steel, and plant-based straps: the Doppio Solar Skeleton does not just claim its green credentials, it puts its solar technology on display. That is the difference between a watch that talks about sustainability and one that shows it.

Solar watchmaking spent years waiting for the world to take it seriously. With the Doppio Solar Skeleton, MONDAINE has done something smarter than argue the case. It has taken a functional part of the movement, the solar cell, and made it the point of the design. The result is not simply another solar watch. It is a new reading of what a skeleton watch can be, one that reveals solar technology rather than traditional mechanical components.