Since the 1960s, the introduction of more energy efficient lightbulbs has brought more competition to the incandescent bulbs. Today there are two different types of bulbs that can help us lower our carbon footprint.
Compact Fluorescent Lights (CFLs)
This bulb was introduced in 1973 due to an oil crisis in the US, and since then it’s usage has increased. Unlike incandescent bulbs, CFLs do not contain any filaments. Instead, they are made of two parts: a gas-filled tube (also called bulb or burner) and the magnetic or electronic ballast. When the light is turned on, the electrical energy, which flows through the gas, emits ultraviolet light. The ultraviolet light then excites a phosphor coating on the inside of the tube, this is what makes the light visible [Source: Treehugger]. Since these bulbs do not contain filaments, they last around 6,000-15,000 hours compared to incandescents 1,000 hours. Not only that, but CFLs use 75% less energy than incandescent bulbs and in the long run will save the average household [Source: Energy Star] between $44-1,500 per year [Source: Wikipedia]. As demand for CFLs has increased, so has the technology. Many of these lights now emit a “soft-white” light (rather than the harsh white of many tube CFLs) and also work in dimmable and three way fixtures [Source: Treehugger].
There are a couple drawbacks with using CFLs. One of the major problems is the use of mercury in these bulbs. While the level is very minute (about 5 mg according to the EPA), when collected in a landfill, these levels could become hazardous to humans and wildlife. Many CFLs have been thrown in the trash, and break when thrown into landfills. The mercury then seeps into the groundwater and soil. This could potentially make its way into drinking water [Source: Free Libary] and our produce. To combat this problem, companies like Home Depot and Lowe’s offer a CFL recycling program.
Beyond the mercury levels, one of the growing concerns of switching over to CFLs has been the increased levels of UV radiation from these bulbs. In early October 2008, the British Health Agency (HPA) investigated CFLs and found that nine out of 53 bulbs emitted unacceptable levels of UV radiation at a proximity of 12 inches or less and for a period of more than one hour per day. Not only that, but those suffering from lupus or other problems caused by the sun are especially susceptible to such UV exposure. The HPA suggests enclosed or globe CFLs for any applications where UV exposure is a concern; the extra enclosure is enough to absorb excess UV. While most people are not in contact with CFLs at such close proximity and for long periods of time, those with CFL desk lamps or who work continuously around these bulbs should take extra precaution to cover the lights.
Light Emitting Diodes (LEDs)
While CFLs are still the main alternative bulbs for many households, LEDs are slowly taking over the market as a much safer and even longer laster light. The first practical use LEDs were invented in 1962 with a $200/unit price tag. Nowadays the cost has decreased significantly, and technology has also advanced these bulbs to emit many shades of color from red to a soft white. While the bulbs are still more expensive than CFLs, they may end up being better for the environment. The main problem with CFLs (mercury) is absent in LEDs. LEDs also last much longer than either bulbs by a longshot at 25,000 hours. Compare that to CFLs max of 15,000 hours. In a recent study by The Department of Energy, LEDs could reduce national energy consumption for lighting by 29% by 2025. That would save U.S. households $125 billion on their electric bills and would have a significant positive impact on global warming, energy and emissions initiatives [Source: The Daily Green]. Large corporations like Starbucks are planning on installing LEDs for all the new stores that open worldwide.
One of the major disadvantages of LEDs, besides the initial cost, is the color of the LEDs, most notably blue LEDs. Blue LEDs are much brighter than their red or green counterparts and can cause greater eyestrain and fatigue than any other color. It can also interfere with internal body clocks, disrupting sleep patterns. Even low levels of blue light during sleep might weaken the immune system and have serious negative implications for health [Source: Texyt]. While you can avoid the true blue LEDs, even the cool-white LEDs emit proportionately more blue light than standard incandescents or CFLs. This causes blue pollution and when used in outdoors spaces (think Times Square) can cause significantly more light pollution [Source: Wikipedia]. Another major disadvantage of using LEDs is that they do not light a room as well as incandescents and fluorescent lights.
In February 2010, RTI introduced nanofiber lamps, which use LEDs and combines flexible photoluminescent nanofiber technology and nano-fiber based reflectors in order to create white light. These bulbs can generate an excess of 55 lumens per watt and can range in color from warm white to cool white [Source: RTI].