What if your watch could turn the light around you into the energy it needs to keep running?
That is the idea behind Citizen Eco-Drive, a technology designed to power a watch using light instead of requiring regular disposable battery replacements.
It Uses More Than Sunlight
Despite sometimes being described as “solar-powered,” a Citizen Eco-Drive watch does not rely only on direct sunlight.
Eco-Drive can use both natural and artificial light, including:
- Sunlight
- Indoor lighting
- Office lights
- Lamps
- Other everyday light sources
This means the watch can continue generating energy during normal daily wear, even when most of your time is spent indoors.
How Is Light Turned Into Power?
The Eco-Drive process can be explained in three simple steps:
1. Light Passes Through the Dial
In many Eco-Drive watches, a solar cell is located underneath the dial.
Citizen carefully designs the dial to be translucent enough for light to pass through while still concealing the solar cell underneath. This allows the watch to maintain an attractive, traditional appearance.
2. The Solar Cell Converts Light Into Energy
Once light reaches the solar cell, it is converted into electrical energy.
Citizen describes the Eco-Drive mechanism as:
Convert. Store. Drive.
The watch converts light into electricity, stores the energy, and uses it to drive the movement.
3. Excess Energy Is Stored
Energy that is not immediately needed is stored in a rechargeable power cell inside the watch.
This stored energy allows the watch to continue operating at night, inside a drawer, or anywhere else where light is temporarily unavailable.
Will an Eco-Drive Watch Stop in the Dark?
A fully charged Eco-Drive watch can continue running even when it is no longer exposed to light.
According to Citizen, many Eco-Drive models can operate for more than six months in complete darkness after receiving a full charge. Certain models equipped with a power-saving function can operate for much longer.
The exact power reserve depends on the model and the functions it includes.
Does It Ever Need a Battery Replacement?
Eco-Drive watches use a rechargeable power cell rather than a traditional disposable watch battery. Because that cell is continually recharged by light, regular battery replacement is not required.
This is convenient for the owner and helps reduce the number of discarded watch batteries.
Citizen reports that its light-powered technology has helped prevent more than 100 million batteries from entering landfills since the company introduced its first light-powered analog watch in 1976.
How Can You Tell When the Charge Is Low?
Some Citizen Eco-Drive models include an insufficient-charge warning.
When the stored energy becomes low, the second hand may begin moving in two-second intervals instead of its normal one-second movement. This is the watch’s way of letting you know that it needs more exposure to light.
After the watch receives enough light and rebuilds its charge, the second hand should return to its normal movement.
Features can vary, so always refer to the instructions provided for your specific Citizen model.
Does Eco-Drive Mean the Watch Never Needs Maintenance?
Eco-Drive greatly reduces the need for routine battery changes, but the rest of the watch should still be properly cared for.
The bracelet, clasp, crown, crystal, seals, and water-resistance components may still need professional attention over time. Avoid leaving the watch in complete darkness for extended periods, and allow it to receive regular exposure to light.
Citizen recommends occasionally exposing an Eco-Drive watch to direct sunlight for the best charging results.
Fifty Years of Light-Powered Innovation
Citizen introduced the world’s first light-powered analog quartz watch in 1976. Over time, the technology developed into what is now known as Eco-Drive.
Today, Eco-Drive can be found in everything from classic dress watches to chronographs, dive watches, titanium models, and advanced timepieces with atomic or satellite timekeeping.
Find Your Citizen Eco-Drive Watch
Whether you prefer something classic, sporty, rugged, or sophisticated, Citizen offers Eco-Drive watches for many different styles and lifestyles.
Explore the Citizen watches currently available at Pineforest Jewelry ›
Looking for a particular Citizen model, dial color, bracelet, or feature that you do not see online? Pineforest Jewelry also offers special orders. Let our team know what you are looking for, and we will be happy to check availability.
Sources and Credit
Information for this article was prepared using educational material provided by Citizen Watch:
Power reserves, charging times, warning features, and power-saving functions can vary by model. Consult the instructions for your specific Citizen watch for complete information.