LED light bulbs are becoming increasingly popular with designers and consumers of green technology, as they use less electricity, last longer, and emit more light than traditional incandescent bulbs. But there’s still a lot to be improved upon.
The world is facing a very serious environmental crisis. Among the different factors contributing to the dilemma, lighting is one of them.
Impact of lighting on the environment
Lighting affects the environment in a number of adverse ways, including energy usage, materials used to produce lighting products, and light’s impact on the nighttime sky also known as light pollution.
There are 3 dominant types of lighting at the moment – incandescent, LED, and CFLs – and among these, LEDs have the least overall impact on our environment according to a number of studies based on energy-efficient lighting. Let’s see how.
Components & materials used for production
More the material needed for production, bigger the impact on the environment
All three light bulbs use similar materials such as tinplate steel for the Edison screw, and copper, solder and insulate in their base assembly. However, LED bulbs require additional porcelain material. While incandescent light bulbs don’t require any ballast or drivers, both CFLs and LED bulbs require different types of printed circuit boards, resistors, transistors, inductors, capacitors, diodes and copper wire which make the bulky base of those bulbs.
LEDs require additional Teflon tubing which improves the insulation of the circuit in order to prolong its operation according to their projected lifespan. Optics of all 3 types of lighting relies on different types of glass, whereas LED bulbs require additional plastics. CFLs require usage of mercury as a glowing gas, electrodes as the filament, as well as plastic, glass, and copper wire for its housing.
A similar type of housing and same materials are required by LED bulbs, while they use LED module to provide the light and it consists out of LED die, aluminum, plastics, and copper wire. Incandescent light bulbs are fairly simpler and require Tungsten as a filament. Currently available LED bulbs require additional heat sink which enables their cooling and longer operation, and those heat sinks require usage of additional aluminum, copper and plastic.
This brings us to a simple conclusion that the most complicated process in light bulb production goes to LED bulbs, followed by CFLs, while the production of incandescent light bulbs require the least complicated process.
Why then do lighting experts still consider LEDs as the most environmentally friendly option?
Energy usage and its impact on the environment
Longer lifespan reduces the frequency of disposal of lamps
In spite of the number of materials used in the manufacturing process, power consumption and invariably the life span of the product can change the overall impact of a lighting device on the environment. This is where LEDs score an advantage. The lifespan of a single LED bulb is equivalent to the lifespan of 3 CFLs, which is equivalent to the lifespan of 22 incandescent light bulbs. So, in the long run of operation and bulb replacement, LED bulbs are the least material consuming.
LEDs: A green technology ‘still in the making’
LEDs are considered a green technology as they are energy efficient as they consume less energy than other light sources for a given task, have a long lifespan (upto 80,000 hours) which means fewer replacements and do not contain mercury or other harmful gases or emit any harmful UV rays.
Although LEDs are more efficient than most other light sources, a major hiccup in LED design is an important component called heat sink which is a problematic area. LEDs are cool to the touch because they generally don’t produce heat in the form of infrared (IR) radiation. On the other hand, LEDs generate heat in the diode semiconductor structure (in addition to photons) and this heat must exit the system through conduction and convection.
Effective cooling of high-powered LEDs for homes, offices and streetlights is a serious engineering challenge as it affects LED performance, longevity, and even lamp safety. Heat sinks serve to draw away heat from LEDs to ensure long life but also add to an LED bulb’s costs. The aluminum contained in an LED lamp’s large aluminum heat sink causes a greater impact on landfills because of the energy and resources consumed in manufacturing.
Packaged LED manufacturers spend considerable time constantly improving all elements of component design, manufacturing, and packaging to optimize efficiency. Improving the efficiency of an LED lamp would mean a reduction in the amount of heat the lamp produces and the size of heat sink it requires. Thermal management represent about 25-30 percent of total cost in an LED bulb, second only to the LEDs themselves. Improving thermal performance would mean a reduction in overall cost.
LEDs surpass 100 lumens per watt
Many LED companies are making major breakthroughs in increasing the efficiency of LEDs. Between 2012-2014, LED efficiency jumped from 60 lumens per watt to 100 lumens per watt and may soon hit the 150 lumen per watt mark by 2020. GE Lighting released the first ENERGY STAR qualified LED bulb to achieve 100 lumens in 2014. It was the first to achieve 100 lumens per watt, making it the most efficient bulb of this kind. At 1600 lumens and 16 watts, this bulb is best suited for consumer requirements for brighter LEDs in reading lamps or task lighting but can also be used in various commercial applications, such as in hotel rooms.
Increase in blue LED chip efficiency
Osram achieved one of the best values in the world in terms of forward voltage for blue-high current chips. This has led to an increase in efficiency of up to eight percent. According to Dr. Marcus Eichfelder, Project Manager at the Regensburg high-tech company, the reduction in forward voltage was achieved thanks to a new process in the epitaxy.
The blue Osram Oslon Square (LD CQAR), for example, now has a typical forward voltage of only 2.87 volts (V) instead of the 3.05 V specified so far in the data sheet – the lowest typical values in this component class worldwide. At 85° C a voltage of 2.78 V can be achieved in the component. Depending on the operating point, this translates into an increase in efficiency of these light emitting diodes (LEDs) of six to eight percent, which can be transferred to the entire UX:3 chip family. These chips can be found in all blue and white LEDs. The LEDs are used in an extremely wide range of applications – the Osram Oslon Square, for example, in street lighting and industrial lighting. (Inputs from Osram’s press release).
Improvement in secondary optics to maximize performance
Cree new XLamp® XP-L High Intensity LEDs is the first of Cree’s new class of high intensity LEDs optimized to deliver double the candelas of previous single-die LEDs through secondary optics, while reducing the amount of lumen loss. Built on Cree’s breakthrough SC5 Technology Platform, the new component innovation radically lowers the system costs for maximum performance in high intensity applications like indoor, track and stadium lighting.
Heat pipe design: New patent pending technology
Gembird Europe BV, a European manufacturer computer-related products has created an LED bulb based on (patent pending) heat pipe design. Heat pipes are a common solution for cooling computer CPUs but so far have never been used in LED bulbs.
Providing a far greater lit area of 330 degrees as compared to the 140-160 degrees provided by traditional LED bulbs, efficient cooling which ensures there is no decrease in light output over years of use, minimum defect possibility due to distance between the driver and light source, high performance in a closed light fixture and finally the capability to produce 135 lumens per watt, engineers at Gembird believe the EnerGenie LED bulb to be the most efficient LED bulb in the world.
Further improvements in manufacturing processes and electronics will lead LED bulbs to be even more environmentally friendly in the coming years. According to a newly released report from the Department of Energy’s Pacific Northwest National Laboratory and UK-based N14 Energy Limited, by 2017 the LED bulb will have 50 percent less environmental impact than today’s LED lamps.