The amount of light a bulb produces. Depending on which government agency you ask, this is “brightness” or “light output.” Your reference point: A standard 100-watt incandescent produces about 1,700 lumens.
Not a measure of brightness; instead, it’s a measure of how much energy a bulb consumes to reach its claimed brightness.
Fact: We’ve already said goodbye to 75- and 100-watt incandescent light bulbs, and starting January 1, 2014, we’ll also be saying goodbye to 40- and 60-watt bulbs as well. This is due to the Energy Independence and Security Act.
Since we’ve conflated watts and brightness, it’s easier to talk about bulbs in terms of watts. So if a 100-watt incandescent produces 1,700 lumens, and a 20-watt LED does the same, the LED will be sold as a 100-watt equivalent.
The number of lumens a bulb produces for each watt it consumes. The higher the number, the more efficient the bulb. A good number for incandescents is around 18, CFLs around 60, and LEDs around 54.
Turning a bulb on and off, on and off, reduces the Average Rated Life (ARL). Incandescent, halogen, and LED bulbs are less affected by on/off cycles than Fluorescent, Compact Fluorescent (CFL), and HID bulbs. In general, the ARL for a bulb that turns on and off once a day will be much longer than a bulb that turns on and off many times a day.
LEDs dim over time. They’re considered effectively dead when they produce no more than 70 percent of their original brightness. For LEDs, this lifespan is given in hours of years, the latter an estimate based on three hours of daily use.
Typical Average Rated Life (ARL) for Types of Light Bulb
Incandescent 750-2,000 hours
Compact Fluorescent (CFL) 8,000-10,000 hours
LED 40,000-50,000 hours
Based on an assumption of three hours of use per day at 11 cents per kilowatt-hour. For a 60-watt incandescent, it’s just over $7 per year. CFLs and LEDs both come in at about $1.50 per year.
LIGHT BULB TYPES
Three of the most common types of light bulbs are energy-saving Incandescent, CFL and LED.
INCANDESCENT BULBS: 25% ENERGY SAVING
Incandescent bulbs use a filament that’s heated to the point of glowing. The glowing filament produces the bulb’s light.
• Incandescent bulbs last on average 1 year.
• Incandescent bulbs do not contain mercury.
• Can be used with a dimmer switch.
CFLS: ABOUT 75% ENERGY SAVING
CFLs are quiet, instant-on and have warmer, color-corrected tones. They can be used anywhere you would use a typical incandescent light bulb.
• Compact fluorescent lamps (CFLs) last up to 9 year.
• CFLs contain small amount of mercury.
• Available in medium bases to fit standard light sockets, such as table lamps.
LED: ABOUT 80% ENERGY SAVING
LEDs are a type of solid-state lighting — semiconductors that convert electricity into light. They have lower wattage than incandescent bulbs, but emit the same light output. This allows them to produce the same amount of light, but use less energy. As with the CFL, Light Emitting Diode (LED) bulbs are the most energy-efficient light bulb options.
• LEDs are more expensive that the last two options but last up to 20+ year.
• LEDs do not contain mercury.
David Hakimi is a lighting specialist and one of the co-founders of Alcon Lighting. A graduate of the University of California Los Angeles (UCLA), David works on the front lines of the energy-efficient lighting revolution, enabling architects, designers, and lighting engineers to transition from outmoded halogen and fluorescent lighting to what David calls “the ideal replacement for all lighting applications,” —LEDs. David takes particular pride in Alcon’s design, energy, and green building knowledge, tracing his and Alcon’s commitment to quality, innovation, accountability and value back to the lessons learned from his father, a Southern California lighting salesman and consultant for more than two decades. Passionate about reducing climate change and protecting the environment, David has been particularly valuable in ensuring that his clients and customers comply with rapidly-evolving green building codes. You can connect with David on LinkedIn at https://www.linkedin.com/in/david-p-hakimi/.
When designing for a retail space, it is important to consider not only the design aesthetic that needs to be achieved but also the patron and the intended experience.
Lighting design for retail spaces vary from displaying delicate pieces of jewelry to endless shelves of apparel; and when it comes to coffee shops, the detail and effort into lighting design is no different. Min Cho and Jill Enomoto, directors of store design for Starbucks, share their tips on how to use light to welcome and guide customer experience.
Whether you’re upgrading the lighting in your current office, or designing the office space of a new development project, it’s important to consider the advantages and disadvantages of LED Lighting. Here are 4 important points of analysis when considering LED Lighting to Fluorescent.
Contrary to their domesticated canine counterparts, cats don’t need constant attention. They generally lie low by lounging in the sun or trying to cram their bodies into small undersized cardboard boxes. In fact, most of the time, their humans are in the way. As proof, here’s a collection of architectural photographs where the photographers were inconveniently in the way.
It’s widely known that lighting can affect one’s mood — hence the common term mood lighting. But the degree at which your mood is affected by lighting might surprise you. In 2014, the Journal of Consumer Psychology published a study that found the more intense the lighting, the more affected and the more intense the participants’ emotions were — both positive and negative.
Early in his architectural journey almost 70 years ago, now-renowned architect, educator, and urban planner Balkrishna Doshi made a quiet, powerful promise to himself in his diary, “It seems that I should take an oath and remember it for my life-time: to provide the lowest class with the proper dwelling.” And for the next six decades he lived up to his oath.