The Decline of the Incandescent Light Bulb
The incandescent light bulb provides a warm and familiar glow. But its inefficient use of energy translates to higher electricity bills and contributes to carbon emissions. As such, most forward-thinking nations have started phasing out these bulbs.
The classic incandescent light bulb has a metal wire filament inside an airtight glass envelope that is heated by an electric current. Several variations exist, including a halogen bulb that uses halogen gas to extend its lifespan.
Energy Efficiency
While they’re still widely available in many stores, the majority of light bulbs sold today are LEDs, not incandescents. These newer bulbs produce far more light than their predecessors, and they’re much more energy efficient too. The switch to LEDs could save consumers and businesses money while also reducing carbon emissions, which are linked to climate change.
Until recently, incandescents were still the dominant lighting option, but they’re now being banned under federal energy efficiency regulations. The rules, which took effect Tuesday, ban the manufacture and sale of incandescent bulbs that don’t meet certain minimum energy-efficiency standards.
The Energy Department’s standard was designed to encourage manufacturers to use better materials and develop technologies that would reduce waste and emissions. The standard is based on a measure called luminous efficacy, which measures the amount of visible light produced by a bulb per watt of electricity it uses.
A traditional incandescent bulb relies on electrical current passing through a resistive material, such as a tungsten filament, output speed sensor to generate heat. The heat causes the atoms in the filament to temporarily jump out of their original orbital positions, releasing energy in the form of light.
But only two to three percent of the electricity that powers a traditional incandescent light bulb is actually used to emit visible light. The rest is lost as heat.
Light Output
The light output of an incandescent light bulb is a key factor that determines how much brightness it produces. Most light bulbs are rated for their brightness in lumens. The higher the lumens, the brighter the bulb. Many manufacturers also list a wattage equivalent on their packaging. This number is a rough estimate of how much light a particular bulb produces, but it can be misleading.
When an incandescent light bulb is hooked up to a power source, the electric current heats up a metal filament (typically tungsten) until it glows. The light from the bulb is produced by electrons bumping into the metal atoms. Only 10% of the energy used by an incandescent light bulb is converted to light. The rest is lost as heat.
Inventors have experimented with incandescent lighting for over 200 years. In 1850, Warren de la Rue invented an incandescent arc lamp with a platinum filament. Other inventors, including Edward Shepherd, William Robert Grove, W.E. Staite, and John Daper, continued to develop more practical versions of the light bulb.
Incandescent light bulbs are not very efficient and produce a lot of heat. This heat increases the load on a building’s air conditioning system. They also produce less light than other types of electric lights. Some states and cities have passed laws limiting the use of certain types of incandescent bulbs.
Lifespan
The average incandescent light bulb has a lifespan of around 1,000 hours. But there are many different types of bulbs that can last much longer than this. Be sure to check the bulb’s listed lifespan before making a purchase.
The lifespan of an incandescent bulb is affected by how often it is turned on and off. A light that is constantly being turned on and off puts the filament under more stress than a light that is turned on for a short time. This can cause the filament to burn out sooner.
A light bulb’s lifespan also depends on the temperature of the filament. Hotter filaments have shorter lifespans than cooler ones. The lifespan of an incandescent light bulb can also be affected by the type of socket it is used in. Some sockets are designed to accommodate more delicate bulbs than others.
Incandescent light bulbs can be compared to other lighting options by their luminous efficacy, or the amount of visible light they produce for each watt of electrical power consumed. The higher this incandescent light bulb figure is, the more efficient a bulb is. The best bulbs have a luminous efficacy of over 100 lumens per watt. The lowest rated bulbs have a luminous efficacy below 60 lumens per watt. This means they are only slightly more efficient than an incandescent light bulb.
Cost
While the upfront cost of an incandescent light bulb is cheaper than LED bulbs, it’s more expensive to maintain this type of lighting because it uses a lot of energy. It also has a short lifespan and requires frequent replacements. Consequently, it is best for areas that aren’t used frequently and require less maintenance.
Incandescent bulbs don’t produce the most light, but they do emit a good amount of heat. Most of the electric power they use is emitted as heat rather than light, which makes them less energy efficient than newer technologies like CFLs or LEDs.
Fortunately, the US government’s ban on most incandescent light bulbs has prompted companies to develop more effective alternatives. In addition to reducing greenhouse gas emissions, these alternatives will save you money on your energy bills.
Edison and his Menlo Park colleagues experimented with many variations on the incandescent light bulb before creating a practical model. The filament they eventually settled on was made from platinum, which had a high melting point. This was essential to achieving the bulb’s high vacuum and efficiency, which were both necessary for commercial viability. Inventors before Edison, such as Warren de la Rue and Joseph Swan, had tinkered with carbon and other types of filament to create the electric light bulb. They also struggled to make the bulb viable.
