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How Long Do Seiko Solar Watches Last? Here is Your Answer!

Written by Eddie B. Robinson / Checked by Justin Tucker

how long do seiko solar watches last

Do you still have a Seiko solar watch from the late 1970s that you are now wondering if it still works? Did you discover a long-hidden 1980s Seiko solar watch from a box in the attic? Maybe you also asked yourself, how long do Seiko solar watches last?

While Seiko is no Rolex, Omega, or Patek Philippe, it has been one of the world’s most reliable watch brands since 1881. The best part about Seiko solar powered watches is that they continue operating as long as they get light exposure.

So, how long do these wristwatches last? Let us find out.


How Long Does a Seiko Solar Watch Last?

Seiko guarantees its solar watch batteries to last at least a decade. Unfortunately, some factors can impact the wristwatch’s longevity.

For example, frequent recharging can shorten the battery’s lifespan. Instead of getting eight to ten years’ worth of power, you will only have six or less.

In such instances, having a service center install a Seiko solar watch battery replacement is an excellent option, especially if you are fond of your wristwatch.

It is worth noting that a fully charged Seiko solar watch will operate for at least six months. If you are judicious in your care, you can extend it to a year or so.

You might also want to avoid placing your Seiko solar watch in direct sunlight to prevent device malfunctions. Some people might think it is an excellent idea to leave the solar watch on the car’s dashboard to charge, but doing so might also cause the wristwatch to fail.

What Is the Evolution of the Seiko Solar Watch?


Roger Riehl produced the world’s first solar watch in 1968, which went into production in 1972 as Synchronar. The first mass-produced solar watch looked more like a gadget from Star Trek than what many people associate with wristwatches.

In 1976, Citizen developed its solar-powered analog wristwatch, the Crystron. A year later, Seiko introduced its solar watches. Together with Citizen and Casio, Seiko captured the imagination of wristwatch fanciers.

Seiko solar watches underwent significant breakthroughs and innovations spanning 44 years. Hence, 1970s Seiko solar watch models will be less efficient than their more contemporary counterparts.

For example, a 1980 Seiko solar watch battery might only last five to six years. On the other hand, 21st century Seiko solar watch battery life can reach at least ten years.

The integrated photovoltaic cells of the 1970s and 1980s-era Seiko solar watches are also less efficient than 2010s’ miniature solar panels. The technology improvement translates to better solar energy conversion, improved solar efficiency, and increased durability.

There is also improvement in the design. No longer are Seiko solar watches the same quartz timepieces the brand is famous for. You also get trendy, sporty, and dressy devices to track time.

Technological advances also solved many early Seiko solar watch problems. You get a reliable and accurate timekeeping device that runs for many decades.

Hence, you can say contemporary Seiko solar watches are more durable than their predecessors.

Do Seiko Solar Watches Rely Only on Solar Power?


One thing that separates Seiko solar watches from other brands is their power source versatility. Although these wristwatches require sunlight to charge their batteries, solar is not the only energy source.

These timekeeping devices can continue working for as long as there is light in the environment, including artificial light. You can charge a Seiko Solar 100M indoors and outdoors. As long as you have a light bulb or any other lighting fixture, your Seiko watch should perform optimally.

However, it would be best to understand that artificial light sources are less efficient than direct sunlight.

Related guide: Guide to reset Seiko solar watch.

How Long Does It Take for a Seiko Solar Watch to Recharge?

Seiko solar watches can achieve a full charge status within three hours on a bright and sunny day. However, you cannot expect the second hand to start moving instantly because the wristwatch needs about eight minutes to do so.

The good news is that during sunny weather, Seiko solar watches require only a minute of direct sunlight to maintain one-day operation.

On the other hand, charging the Seiko solar watch on a cloudy day takes ten hours, with the first second-hand movement occurring after 30 minutes. It also requires three minutes to maintain one-day usage.

You can expect a full-charge status in 250 hours or about 10.5 days if you choose to recharge the wristwatch with a 500-lumens, 60-watt incandescent bulb placed about two feet away from the Seiko solar watch. A 1000-lumens 30-watt fluorescent lamp needs 175 hours to charge the solar watch.


Modern Seiko solar watches can last at least a decade because of the various innovations introduced into their design. You might have a different answer if you refer to earlier Seiko solar watch models in asking the question, how long do Seiko solar watches last?

If you have this timekeeping device, take care of it like you would any prized possession. Charge it only when its battery is empty to optimize its charging cycle. After all, a single charge only lasts three hours on a sunny day, and it already lasts up to a year.

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