Shining a Light on Sustainability

Lighthouses have been guiding mariners home since the times of The Iliad and The Odyssey in the 8th century BCE. They may have begun as fires on top of hills, known as beacon fires, but they have developed quite magnificently since the times of Homer. 

Considered to be one of the oldest lighthouses in the world, the Pharos of Alexandria was started during the time of Alexander the Great in Pharos, Alexandria in Egypt. It served as the prototype of all future lighthouses and was one of the seven wonders of the Ancient World. It collapsed after a series of several earthquakes many centuries later. Photo from Oldest.org 

Lighthouses began as wood fires, coal fires, and eventually massive oil lamps that were sheltered in glass and relit every couple of hours by the solitary lighthouse keeper. The conical shape developed as architects battled the windy coasts and employed advancements in structural research. And while I could go on for hours detailing the magnificent symbol of safety and home that lighthouses represent for ocean-travelers across the centuries or the bravery of the watchers who devoted their lives to guiding seafarers through the murky waters and extreme weather events of the coasts of the world, I won’t. Rather, lighthouses are also a symbol of another guiding light in the modern era — sustainable energy. 

This lighthouse was built by the Romans in 43 AD and is part of the Dover Castle Museum in the South East England county of Kent. Photo by Luc Hermans via Pictures of England (2005)

One lighthouse used to burn up to almost 300 tons of coal a year and they emitted massive amounts of black smoke that had to be cleaned off the glass windows regularly. As technology developed, and as mathematicians and scientists discovered that mirrors and lenses could dramatically increase the output of light, the lighthouse began to change along with the duties of the lighthouse keeper. 

The first lighthouse to use electricity in the United States was our very own Statue of Liberty, which transferred to an electrical system in 1886. However, since the beginning of the 21st-century, lighthouses have seen what some call the LED revolution. It started with LED light testing on signaling buoys but gradually progressed to more-efficient lights for lighthouses.

Research conducted on an existing lighthouse in Italy in 2014 determined just how effective LED lighting could be for the industry, concluding that their LED-light (which was actually a collection of multiple LED lights, was verifiably satisfactory in meeting “illumination requirements of the marine signaling norms” and that it was advantageous because it resulted in “reduced energy consumption, enhanced efficiency, longer life, decreased faults, slower aging, and lower maintenance costs” as well as increased durability and reliability. While concluding that LED replacements resulted in 30 percent less light than an incandescent lightbulb, this was proven to be a worthy disadvantage because it was easily outweighed by the power-saving qualities and increase in reliability, as well as the fact that lighthouse repairs, which are funded by taxpayers, that used to cost millions of dollars now cost less than $30,000. Also, LED lights turn on instantly, whereas traditional lightbulbs take some time to warm up.  

The SL-LED Light from Sealite’s High Output LED Lighthouse Source Series; Photo via Sealite.com

Replacing traditional light models like the halogen-tungsten lamps and incandescent lightbulbs has become a major priority in the marine signaling industry because it saves energy, reduces light pollution which increasingly plagues our modern world, and requires a lesser financial investment. The majority of mariners rely on GPS signals for navigation, so light-signaling buoys and lighthouses serve as an extra guide nowadays. The U.S. Coast Guard has begun replacing older lightbulbs with LED lights and transferring lighthouse power from electrical to solar power as it did with Cape Lookout Shoals in North Carolina in 2017 to reflect a changing industry and a world transformed by the effects of climate change. Similar changes have been made all along the coast and in key areas like Florida, where the coral reefs are still very difficult to navigate. 

A lighthouse doesn’t save the ships; it doesn’t go out and rescue them, it’s just this pillar that helps to guide people home.     

Lea Michele

Happy National Lighthouse Day from Eco18! 

Catie Brown

Although I’ve always loved writing, I embarked on my journey into science journalism about three years ago. I am fascinated by all things water — oceans, ice, coral reefs, currents, extreme weather, sanitation, energy, and (of course!) climate change. I also love looking into the different ways we talk about climate change as a social, cultural, economic, spiritual, and political crisis. Big thanks to coffee and chemistry jokes for keeping me going. Happy reading!