Let there be light!....Sustainably?

Updated: Sep 15, 2020

There's an old saying that goes something like this, "Charity begins at home"....while this may be true, charity isn't the only thing that can start from your home.


Most people think the only way to make their homes and business more sustainable and "greener" by conserving energy is to switch to renewables, however there are simpler, inexpensive ways to do so that many take for granted. One simple change that can go a very long way is through a change in the light-bulbs  one uses around their home.  

In Trinidad and Tobago, we usually use incandescent or Compact Fluorescent (CFL) light-bulbs, with CFL being the smarter choice of the two. However, there is an emerging technology which has the potential to be a step up from CFL bulbs called Light Emitting Diodes or LED.


Here is a comparison of all three types of bulbs:

1. Incandescent Bulb:

The incandescent light bulb or lamp is a source of electric light that works by the emission of light caused by heating the filament.



2. CFL Bulb:

In a compact fluorescent bulbs, an electric current is driven through a tube containing argon and a small amount of mercury vapour. This generates invisible UV light that excites a fluorescent coating (called phosphor) on the inside of the tube, which then emits light.



3. LED Bulb:

The average light emitting diode works through what is known as a “p-n junction”, which is formed of a p-type semiconductor (which contains positively charged carriers) and an n-type semiconductor (which contains electrons). This is when the color starts to change and light is being emitted by the LED.

LEDs are "directional" light sources, which means they emit light in a specific direction, unlike incandescent and CFL bulbs, which emit light and heat in all directions. LED lighting is therefore considered to be able to use light and energy more efficiently.



1. Energy Efficiency and Energy Costs

  • Life Span:

Incandescent = 1 200 hours

CFL = 8 000 hours

LED = 50 000 hours

LED bulbs have a longer lifespan than CFL and Incandescent bulbs.

  • Energy Use:

Incandescent - Consumes = 100 Watts; Emits = 60-80 Watts

CFL - Consumes = 24 Watts; Emits = 100 Watts 

LED - Consumes = 12-15 Watts; Emits = 75-100 Watts

LEDs consume the least energy, while having a larger output of energy.

LEDs use less power (Watts) per unit of light generated.


2. Environmental Impacts

  • Greenhouse gas emissions:

For 30 bulbs per year, carbon dioxide emissions stand at: 

Incandescent = 4500 pounds per year CFL = 1051 pounds per year LEDs = 451 pounds per year 

LEDs help reduce greenhouse gas emissions and aid in achieving a lower electricity bill, due to the less amount of energy required.

  • Mercury Content:

Mercury is highly toxic to human health and the environment.

LEDs and Incandescent bulbs do not contain mercury, unlike CFL bulbs.

  • Restriction of Hazardous Substances (RoHS) Compliant:

RoHS originated in the European Union and restricts the use of certain hazardous materials found in electrical and electronic products.

LED and Incandescent bulbs are RoHS compliant, unlike CFLs.


3. Important Facts 

  • Sensitivity:

CFLs may not work under 10 or over 20 degrees Fahrenheit, and are also sensitive to humidity. Some incandescent bulbs are sensitive to both low temperatures and sensitivity.

However, LEDs are not sensitive to low temperatures or humidity.

  • Durability:

Incandescent/CFLs = can break easily

LEDs = very durable 

  • On/off cycling:

Switching on and off quickly affects the bulbs in the following ways...

CFL = can drastically reduce the lifespan of the bulb 

LED = does not affect it

  • Turning on

Incandescent = instantly 

CFL = takes some time to warm up

LED = instantly 

  • Failure

Incandescent = only occurs i