Incandescent Bulbs - Popular but Not Energy Efficient
Incandescent bulbs were introduced in 1879 by Thomas Edison. What many people do not realize is that up until about 10 years ago these were still the most common form of light bulbs in use!
The incandescent bulb was used everywhere and could be found in homes and offices. They provide a nice warm glow but are not energy efficient! Over 90% of the energy used by incandescent bulbs is given off as heat. They are extremely hot to the touch, and the underlying technology has not changed significantly since they were invented over a century ago.
Halogen - Similar to Incandescent But Longer Lasting
Halogen lights which give the feel of daylight became readily available in the 60’s and had greater efficiency than the incandescent and has been a favorite light source for many applications. However, halogen lights also produce a significant amount of heat.
Fluorescent Lights Have Been in Offices for Over 50 Years
Typically found in the form of tubes - these have gone from T12 (Which are 1 1/2 inches in diameter) to T8 and more recently T5. The tube diameter has gotten smaller with the T5 being just over ½ an inch. As they have gotten smaller in diameter, they have also become more energy efficient and have a longer life. Fluorescent tubes are powered by ballasts, going from magnetic ballasts to more efficient electronic ballasts. For many years there were rebates from utility companies which made conversion to these smaller tubes a wise business decision. However, fluorescent tubes are problematic for several reasons. They tend to have an audible hum and also have a flicker which is visible to some people and can cause eye strain and headaches.
Compact Fluorescent Lights - Energy Efficient With a Cost
CFL’s (Compact Fluorescent Lights) began replacing the incandescent bulb in the 90’s. They provided energy savings compared to incandescent type bulbs. They used the same fluorescent bulb technology but were adapted to a smaller form that would fit in downlights, table and floor lamps. However, they have drawbacks: they require a warm-up time so do not illuminate instantly when turned on. They also contain mercury which is hazardous - especially if they break because it is toxic. These lights are often not disposed of properly and can end up going to landfills. These have always been my least favorite type of light. They were brought to market mainly as a go between for incandescent bulbs and the latest technology LED’s.
LEDs - The Emerging Standard
LED’s (Light-emitting diode) have been available for about 15 years. They are now available for just about every light need. They come in multiple form factors including tubes and screw-in forms. LED lights have a longer life, low maintenance costs and substantial energy savings (80-90% over the earlier light sources). By 2030 LED’s are projected to be the most common of light sources. Currently, there are Utility rebates to upgrade to these lights. However the rebates are becoming smaller and soon will be unavailable.
As light sources have changed so have the fixtures that house them. From bulk cloud like fixtures or exposed tube fixtures for fluorescent tubes, to flat panels that look like sky lights for the LED’s. In today’s office environment you can have a look to fit any décor or need.
Human Centric Lighting - The Next Step
HCL (Human Centric Lighting) is lighting that considers our biological need for light. It can provide the correct light at the correct time of day for the task we are doing. It uses LED technology to emit light at specific frequencies to match our biological patterns. For example, we respond to certain light frequencies early in the day versus the evening. HCL lighting can include controls which can be manually changed or set on a predetermined schedule. This is lighting that I am most excited about and believe it will be a game changer for healthcare, offices and schools.