The LED industry has been steadily advancing since the 1960s; this development in LED technology has caused their efficiency and light output to rise exponentially. This trend is generally attributed to the parallel development of other semiconductor technologies and advances in optics and material sciences.  In the early 2000s, processes for growing gallium nitride (GaN) LEDs on silicon were successfully demonstrated. In 2012, high-powered LEDs such “GaN on Si” LEDs were demonstrated to have commercial feasibility.  It has been speculated that the use of six-inch silicon wafers instead of two-inch sapphire wafers and epitaxy manufacturing processes could reduce production costs by up to 90%. The result of these advancements have made LED technologies for consumers more accessible than ever before.

Advantages of LED

  • Efficiency: LEDs emit more lumens per watt than any other light source. LEDs can achieve up to 90% and 40% energy efficiency when compared to typical incandescent and fluorescent lighting respectively.
  • Lifetime: LEDs can have a relatively long useful life with a L70 in excess of 100,000 hours. Fluorescent tubes are typically rated at 10,000 to 15,000 hours and incandescent at 1,000 to 2000 hours. However, this varies greatly depending on the application of the LEDs due to heat degradation. LED tubes typically last 30,000 to 50,000 hours, but high quality LED fixtures can last 100,000 hours or more.
  • Maintenance: LEDs require relatively low maintenance when compared to other light sources. Several reports by the Department of Energy (DOE) suggests that this is where the greatest costs savings are made and not in lower energy costs.
  • On/Off Time: LEDs will light up and achieve maximum brightness very quickly compared to fluorescent which needs to warm up. This makes them perfect for dark rooms where the light is usually off.
  • Color: LEDs can emit light of specific wavelengths to produce colors without using any color filters required by traditional light sources. This means greater efficiency and lower manufacturing costs.
  • Cool light: In contrast to most light sources, LEDs radiate very little heat in the form of IR that cause damage to sensitive objects and fabrics. Instead, heat is dissipated through the base of the LED. In addition, LEDs lower the cost of A/C by reducing energy waste in the form of heat.
  • Flexibility: LEDs can be very small (< 2 mm2) and are easily attached to printed circuit boards allowing for greater design flexibility and full control over how light is emitted from the fixture.
  • Focus: LEDs emit light in the direction where illumination is needed. In contrast, traditional light sources emit light in all directions and therefore require reflectors which increase inefficiencies. An optical lens can also be placed directly over each LED to further focus the light emitted, reducing inefficiencies due to the dilution of the light source.
  • Cycling: LEDs are ideal for applications subject to frequent on-off cycling; they are unlike HPS lights which fail earlier when cycled often or HID lamps which require a long restart period.
  • Dimming: LEDs can easily be dimmed either by pulse-width modulation or lowering the forward current allowing for exceptional lighting control.
  • Shock resistance: LEDs are solid-state devices making them highly resistant to shock caused by physical damage; this is unlike fluorescent and incandescent bulbs which are extremely fragile.

LED Lifespan

Many LED light manufacturers rate their fixtures at 100,000 hours lifespan, but at an ambient temperature of 25°C. In reality, this is not the case for most light applications as ceiling temperature is drastically higher than room temperature due to heat rise. Low quality fixtures struggle to manage this excess heat from the environment. This means that given two fixtures with a similar rated life span, but different build quality, their performance in a more non-ideal environment will be completely different. We take this into consideration when designing all of our light fixtures so that the ideal operating temperature encompasses a wide variety of environments.

“There’s a fundamental flaw with fan-and-heatsink cooling systems: no matter how hard the fan blows, a boundary layer of motionless, highly-insulating air remains on the heatsink. You can increase the size of the heatsink and you can blow more air, but ultimately the boundary layer prevents the system from being efficient; it’s simply a physical limitation of fan-and-heatsink cooling systems –from ExtremeTech.com

The design of our heat sinks are based on the specific thermal foot print produced by the placement of the LEDs; each LED has their own heat signature. This heat signature is carefully mapped and the cooling fins of the heat sink are placed accordingly. We designed some of our fixtures to include fans as an additional cooling component in order to achieve a desired thermal junction (TJ). Although our fixtures already have a low TJ with only passive cooling relative to our competitors, lower temperatures are still desired because it increases the efficiency and longevity of the system.

The function of a heat sink is to transfer heat from one place to another. The problem is that traditional heat sinks must first go through a heat soak phase before it starts dissipating heat.

Our design does not wait for this phenomenon to happen and gets rid of the heat right where the heat signature of the LED is produced. This is our proprietary technology and it is our “Competitive Advantage”. By utilizing this approach, we can maintain a constant temperature of 51°C TJ. This is an important factor since the temperature of the LEDs will determine several factors:

  • Light efficiency
  • Longevity
  • L70 of the fixture

Our heat sinks are designed to perform only with passive cooling. The LEDs we utilize for our lights can safely operate up to 105°C

Extrusion VS. Die Casting

Die casting, when compared with extrusion, are used to cut production costs. In our heat sinks, aluminum extrusion produces a structure with relatively good dimensional outcome; die casting requires extensive finishing before use. This is a key factor for our heat sinks since the location of the fins cannot vary because of the heat signatures of the LEDs. Also, there is no way for us to control the molecular flow and structure of cast aluminum. In contrast, the extrusion method produces a heat sink with a very consistent molecular structure resulting in superior thermal conductivity.

Non-recycled vs recycled aluminum

The extrusion process also requires higher quality non-recycled aluminum; recycled aluminum has large amounts of impurities which result in an inconsistent molecular structure. The result of this is inferior thermal conducting properties which cause poor heat management and high operating temperatures.

The external housing and LED circuit boards for all of our fixtures are also made from extruded, non-recycled, aluminum. Lower quality circuit boards are more insulating and cannot sufficiently transfer heat from the LEDs to the heat sink.

Most lighting applications have traditionally used either high pressure sodium (HPS) or high intensity discharge (HID) lamps. HPS are mostly used in street lighting, high-bay, and industrial applications, therefore, they will be our focus. There are two kinds of sodium lights: Low Pressure (LPS) and High Pressure (HPS). The lamp works by creating an electric arc through vaporized sodium metal.

Some points to consider regarding HPS lighting:

  • The light must warm up before working at full capacity taking anywhere from 2 to 15 minutes.
  • They use a ballast, typically consuming anywhere from 20% to 50% in addition to the energy consumption of the light bulb.
  • Dimming capabilities can be at a maximum of up to 50% of the total light output.
  • These lights produce a surface temperature of around 215° Celsius.
  • A 100 Watt HPS lamp contains around 6mg of mercury which eco-unfriendly and harmful to humans.
  • HPS operational temperature range is -30° to 65°