At some point, you might have wondered, “Aren’t all LED lights the same?” But actually, they aren’t.
Three main factors distinguish high-quality LED fixtures from others: the efficiency of light output and resources, the correct optical options of the fixtures, and the quality and strength of the fixtures. Understanding the differences between each of these elements is crucial when evaluating LED lighting. Here’s a breakdown of each factor.
1. LED Efficacy
LED efficacy refers to how efficient an LED fixture is. It is an equation of total delivered lumens of light output and the total energy consumption it takes to power a fixture (measured in watts). For instance, if a 100 watt LED flood light has 10,000 delivered lumens, the efficacy of that fixture is 100 lm/watt (10,000/100).
Often, estimates that come from larger firms which use the more traditional lighting distribution model (of manufacturer, representatives, wholesale supply house, and contractor) are based on older and outdated fixtures. This can make the estimate seem less expensive and, consequently, a better deal. However, these fixtures can be much less efficient, having efficacies of 80 lm/watt to 120 lm/watt. So what can initially seem like a financially beneficial choice may turn out, in the long run, to be more costly.
By contrast, as LED fixtures continually improve and get more efficient, the efficacy of fixtures has substantially increased: high-quality fixtures have an efficacy of 150 lm/watt to 190 lm/watt.
Why does this matter? Consider a warehouse with 250 fixtures of 400-watt Metal Halide high bays. If you replace the high bays with a fixture with only 120 lumens/watt, you would need a fixture that is 150watts to achieve 18,000 lumens. This is roughly the number of lumens needed to replace a 400w Metal Halide and achieve a noticeable improvement in light levels.
By contrast, if you used a fixture with 180 lumens/watt, you could achieve the same 18,000 lumens with a 100 watt LED high bay. This would result in a slightly lower price per fixture, since, obviously, a 100 watt LED fixture costs less than a 150 watt LED fixture. The lighting difference may not be substantial, as the fixture manufacturer is using the same aluminum mold for both fixtures, but there should be a light-output difference.
But what will be noticeably different in using a 100w LED fixture vs 150w LED fixture is the quicker payback and return on investment for the end user. If you are getting the same amount of light with a 100w fixture, you are saving an additional 50w per fixture. This 50w per fixture times the 250 fixtures in the warehouse results in an additional 12,500 watts of total savings, which will knock off months in your payback calculations.
When comparing fixtures and estimates, make sure to buy the latest technology with the most available energy savings.
2. Correct Optics and Lenses
The second difference between LED fixtures that customers often overlook is the lens type or beam angle on their chosen LED fixtures. Often, inexpensive, lower-quality fixtures come in only one lens type. While this may be acceptable for many standard lighting projects, such as a typical parking lot, it is not sufficient for specialized lighting projects, such as a tennis court or a fixture that is center-mounted on a light pole.
Parking lots with poles that have fixtures mounted to the top of the pole require certain Type 5 lens types in order to provide illumination 360 degrees around the pole. If a standard Type 3 or 4 lens is used, there will be no light coverage behind the pole. This will leave many dark spots around the parking lot.
All flood-type LED fixtures can use different types of lenses on the fixtures to achieve different lighting patterns. For example, tennis court lighting projects also have very specific lens requirements and need a low-glare fixture. Specifically, they require strict lighting spill levels as they are often in residential neighborhoods, so it is very important to use a lens that provides little to no light spill behind the pole, which will limit the amount of light that will “spill” into unwanted spaces. It is also best to obtain a fixture with lower UGR rating (glare rating) to avoid bad glare problems for players.
When requesting quotes on LED lighting for sports facilities such as a tennis court, always inquire about the beam angle of the fixture as well as the distribution type lens the fixture is using. Also make sure you achieve high enough light levels, measured in foot candles (a measurement of illumination), on the court. The last thing you want is to install brand new lighting only to have athletes complain of insufficient light levels.
Remember that the cheapest fixture might not be the best financial investment for these types of specialty projects.
3. Quality and Strength
The last point in comparing LED fixtures is the quality of raw materials and quality of design for a fixture.
First, all high-quality fixtures are made of aluminum. Many cheaper fixtures, especially high bay fixtures, are made of steel. Steel does not dissipate heat nearly as efficiently as aluminum. By using steel, the light degradation and color shift of the fixture will be greatly accelerated, and a yellowing of light and a brightness reduction will become noticeable over time.
Second, the strength of materials is very important, especially in an industrial environment. It is important to make sure that the lights are correctly placed, that they are sturdy enough, and that they project enough lighting. Otherwise, problems such as uneven lighting can occur.
If you are looking to install LED lighting–or to retrofit the current lighting–at your facility, pay attention to the details of your options. Remember, not all LEDs are created equal. Talk to an expert and get the right solution the first time!