Shining a Light on LEDs: Types of Bulbs

This is the first of a 3-part series of blogs written by AmeriCorps Member Phoebe Little, who, along with Grace Sherman, is working with GrowSmart Maine to bring our Energy Efficiency Community Campaign to Biddeford and Windham. We know that energy efficiency and weatherization are pragmatic steps in mitigating climate change that also save Mainers money. While GrowSmart continues to advocate and plan events to highlight connections between smart growth and Maine’s Climate Action Plan and 10-Year Economic Plan, we are also engaging in this community level boots on the ground work for immediate impact. While EV charging stations and renewable energy production are ramping up, simple steps like switching to LED lighting (and knowing how to recycle them) and adding weatherization window inserts through WindowDressers, Mainers are making a difference now. Check out our October and November Window Builds in Biddeford and Windham on our website calendar at

Switching to energy efficient light bulbs is an easy step each of us can take to save money and reduce our energy use. Along with weatherization, this is a common entry point for energy efficiency work for many Mainers. 

Phoebe is a 2020 graduate of Smith College where she studied government and environmental science and completed a thesis on armoring Maine Island communities against sea level rise. In 2021, she graduated with her Masters degree in audio journalism from the Salt Institute for Documentary Studies. She’s thrilled to be back in her home state working with communities to increase energy efficiency.


Shining a Light on LEDs: Types of Bulbs

Phoebe Little
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Everywhere you turn, LED light bulbs are replacing traditional incandescent bulbs and even newer fluorescent bulbs. Making the switch from incandescent light bulbs to more energy efficient options like fluorescent bulbs or LEDs is one of the easiest ways to increase your home’s energy efficiency. This simple step can also lead to real savings on electricity and replacement costs as well as a tangible environmental benefit because in making the switch, less energy usage means less carbon emissions.

In this three part series, we’ll take a deep dive into LEDs: what they are, their benefits, and how to properly recycle them! 

In 2014, the Nobel Prize for physics was awarded to Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura, the team that invented the blue LED light. The team was recognized for “the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources”. Now, LEDs are used in a wide array of applications from televisions to sterilizers and do not contain toxic mercury that is found in fluorescent lamps. These LED bulbs have many benefits including energy efficiency and longevity leading to increased savings on electricity bills- but making the switch from incandescent and fluorescent bulbs can be confusing, especially when there’s a lack of information about proper recycling and disposal. This post provides a Maine-specific guide to energy efficient lighting. 

To learn what an LED light bulb is it’s helpful to first understand what an LED light bulb is not. When you close your eyes and imagine a light bulb you’re likely picturing an incandescent bulb. These bulbs are usually shaped like rounded orbs. They have a thin metal filament that stretches through the middle of the bulb and emits light.

Fluorescent bulbs most often look like a thin tube that’s been twisted up into a spiral. In fluorescent light bulbs, an electric current is driven through a tube containing argon and a small amount of mercury vapor. This reaction generates invisible ultraviolet light that excites a fluorescent coating of phosphor on the inside of the tube, which then emits visible light.

LED stands for light emitting diodes. For a long time, this technology was used only in small electronic displays such as the buttons on VCRs or the clocks on cable boxes. The light emitted by these tiny early LEDs was focused in a specific direction, and not very strong so the technology wasn’t used in household lighting until fairly recently. Advancement in technology over the past few decades has harnessed LED technology to create lights that are bright and suitable for lighting up whole rooms. 

According to the Lighting Research Center, LED light bulbs bring together positive and negative currents to create energy that gets released in the form of light. The result is a fast source of light that is reliable, instantaneous, and able to be dimmed.


Check back next Thursday, as we continue with the second blog post in this series: Shining a Light on LEDs:  Light Bulb Cost Showdown.