The LEDs vs Fluorescents Debate

The Internet has encouraged people from every corner of the world to discuss and debate everything … from politics to pizzas.  Energy-saving LEDs are of course prime topics of ‘virtual’ conversation and few are more energetically debated than whether LED tubes are better than fluorescent lighting. 

LinkedIn, the social networking site, hosted a heated debate between electrical contractors on this very subject.  Every aspect of LED tubes and fluorescent lighting came under scrutiny.  This debate prompted a survey on the use of LEDs instead of fluorescent, conducted by Houston Neal, the marketing director of a US software and technology blog.

The results of the survey, which was focused on commercial lighting applications, predicted a bright future for LED tubes.  They provide greater energy cost savings than fluorescent lighting and they’re better for the environment.

Differences between LED tubes and fluorescents

Fluorescent tubes have been the mainstay of commercial lighting since the 1930s.  Even today, fluorescents are still in daily use in offices, warehouses, shops and factories.  While they’ve done a sterling job, they are not without problems.

Fluorescent tubes contain mercury and argon, so can damage the environment.  They are classified as hazardous waste and must be properly recycled.  The flickering and humming associated with fluorescent tubes has been reported to cause headaches and eye strain.  Fluorescent tubes also generate heat, adding an estimated 2° to the temperature.

A fluorescent tube is very different technology from an LED. The light in a fluorescent tube is produced by electrodes and a combination of argon gas and mercury.  LED tubes are made up of hundreds of individual LEDs.  They can be retro-fitted to old fluorescent fittings as well as being used with new LED fixtures.  (If an LED tube is to be used with an existing fitting, the ‘ballast’ must first be removed.  If in doubt, we recommend consulting your electrical contractor for advice).

Although fluorescent tubes last considerably longer than incandescent bulbs, they still can’t compare with LEDs.  Certainly the initial cost is higher but a replacement LED tube will last at least twice as long as a fluorescent, and use considerably less electricity in its lifetime.  And when you also consider LEDs are non-hazardous, create a better working environment and don’t generate heat, they are clearly the better option and the future of commercial lighting.

Light emitting diode (LED) fluorescent tubes are all the rage in the lighting market. The technology promises to be more energy efficient, less environmentally harmful and more economical than traditional fluorescent tube lighting. Regardless, there is a lot of debate over whether they are ready for widespread commercial use.

We recently came across this very debate being held in a LinkedIn electrical construction group. It was aheated thread with two electrical contractors hashing out the pros and cons of using LED fluorescent tubes. To continue our series of articles on “green” construction, we thought we’d tackle the issue ourselves. So here we present our findings on LED fluorescent tubes.

Survey Results
We recently asked our blog readers and other industry professionals to participate in a short survey on LED vs fluorescent tubes. We received great feedback from participants, so be sure to check out our survey results.

What is a LED Fluorescent Tube?
“LED fluorescent tube” is a misnomer. LED lights and fluorescent lights are completely different technologies. LEDs are very small bulbs illuminated by movement of electrons in a diode. Fluorescent bulbs use electrodes and a gas combination of argon and mercury to produce light. So the name “LED fluorescent tube” really refers to an LED tube that reminds us of traditional fluorescent tubes (likely above your head as you read this).

LED lights should also not be confused with compact fluorescent light (CFL) bulbs. CFLs use the same tecnology as fluorescent tubes to produce light, but on a smaller scale. They are a replacement for the incandescent bulbs commonly found in most home light fixtures. CFLs have garnered a lot of press because of their energy efficiency and environmental benefits (i.e. they use less power).

An LED tube is made up of hundreds of individual LEDs. They come in a variety of sizes (2, 4 or 6 feet), different temperatures (i.e. different colors of light) and varying arrays of LEDs. They can be purchased with new fixtures, or used for retrofitting existing fixtures. But keep in mind, they don’t require ballasts, so those will need to be removed when replacing fluorescent bulbs.

When comparing LEDs to fluorescent tubes, here are four key specifications you should review:

• Lumens – This is the unit of measurement for strength of light. Look for tubes with 1500 lumens or more.
• Watts – This is a unit of measurement for power consumption. Four foot LED tubes typically use 15 to 25 watts, while fluorescent tubes use more than 30 watts.
• Lifespan – This is how long the bulb will last. It’s measured in hours. 50,000 hours is common for LED tubes.
• Color temperature – The temperature of the light is the color of the light. It is measured in units of absolute temperature, or Kelvin (K). 3000K is considered warm (redder), 4100K is considered neutral, and 5800 K is cool (bluer).

Pros and Cons of LED and Fluorescent Tubes
To give recognition where it’s due, fluorescent tubes are a great invention. They have been lighting most of America ever since GE brought them to market back in 1938. They are four to six times more energy efficient than incandescent bulbs and are said to last 10 to 20 times longer. Of course there are disadvantages too.

Fluorescent tubes contain mercury and phosphor which present health and environmental risks. Lights require a ballast which adds to the cost of the lamp and can cause a buzzing noise. Finally, they flicker and the light is often drab.

Meanwhile, LED bulbs last longer than fluorescents, they don’t contain harmful ingredients like mercury and they use much less power than fluorescent lamps. And this is just for starters. LEDs aren’t perfect though. The tubes are generally not as bright and cost more up front. And unfortunately, cost will likely be the number one driver of greater adoption. So let’s compare the costs of each.

Costs of LED Tubes vs Fluorescent Tubes
The debate over LED vs fluorescent tubes always teeters at the cost argument. When comparing the upfront cost of one LED tube to one fluorescent tube, fluorescent wins. However, when you consider volume discounts and the lifespan of LEDs, the scale leans the opposite direction. Let’s compare the costs of each.

This table compares the first-year cost of a single commercial-grade (i.e. UL and CE compliant), four foot T8 LED tube to a four foot T8 fluorescent tube. To measure kilowatts per year, we assumed the lights would be on for 12 hours a day and 255 days a year. We used an average energy rating of 20 watts per hour for LEDs and 32 for fluorescents. To calculate energy cost, we used an average cost per kilowatt of $0.11.

Clearly fluorescents are less expensive in the first year. However, when you account for product longevity, LED tubes are the winner. LED tubes last an average of 50,000 hours (roughly 16 years) while fluorescent T8 tubes last an average of 25,000 (roughly 8 years). To determine this, we looked at every fluorescent T8 tube that Sylvania offers (nearly 150) and calculated average lifespan. To be precise, it was 24,787.67 hours.

In this next table, we compare the 16-year cost (the lifespan of an LED tube) of 40 LED tubes compared to 40 fluorescent tubes. In this example, the number 40 is somewhat arbitrary. We have twenty, 2′ x 4′ fixtures in our office, so we chose 40 bulbs as our comparison. Keep in mind, fluorescent fixtures require ballasts, so we’ll need to tack on an additional $400 to fluorescent tubes (20 ballasts at $20).

Using prices from our previous table, in the first year it will cost $3,069 for the energy and initial purchase of 40 LED tubes. The fluorescent tubes would cost $1,071. Every year thereafter, the energy costs of LED tubes will be $269, and $431 for the fluorescents. In the eighth year, the fluorescent bulbs will need to be replaced at a cost of $240.

You’ll notice the numbers in our table look a little different. That’s because we’ve included an annual energy inflation rate of 5%. We also used a 2.5% inflation rate to calculate the cost of the replacement fluorescent bulbs in the eighth year. Finally, we used a 6% discount rate to determine the net present value (NPV).

As our table reveals, the 16-year cost for 40 LED tubes is $6,431 while the cost for fluorescent tubes is $6,846. This is 6% in savings over the life of the tubes. Keep in mind, this is only 40 tubes. Building owners with more light fixtures will realize more savings as the volume discount will be greater and energy costs will be lower. So, over the lifespan of the product, LED tubes are more cost effective than fluorescent tubes.

A Bright Future for LED Tubes
The cost of manufacturing LEDs is dropping. Researchers at Purdue University have developed a way to create LEDs using inexpensive, metal-coated silicon wafers instead of expensive sapphire-based bulbs. This has the potential to bring the cost down to levels competitive with fluorescent tubes. You can stay up to date on news of this development over at the Eartheasy blog.

In the meantime, there’s no reason electrical contractors shouldn’t promote LED tubes. LED tubes can help building owners become eligible for government and utility company incentives. They help companies reach the desirable – and highly marketable – green cachet. They provide greater energy cost savings than fluorescents. And finally, they are simply better for the Earth. They are the future of commercial lighting.