My name is Justin Luyt. I started this blog in the midst of out 2008/9 recession with the purpose of helping others reduce their monthly expenses. All around our homes we have a multitude of devices, tapping into your bank account every day.Today I wanted to talk about a cool invention on a hot topic. After all, saving the environment, carbon footprint, carbon credits and debits, all these terms are the rage now. A lot of things that were acceptable even 10 to 15 years back have been blacklisted and may soon proceed to being banished for good! Gas guzzling SUVs, generating stations using fossil fuels, logging, non renewable fuel, non renewable fishing methods – the list is endless. Incandescent lamps being another one of them.
Today I wanted to talk about a cool invention on a hot topic. After all, saving the environment, carbon footprint, carbon credits and debits, all these terms are the rage now. A lot of things that were acceptable even 10 to 15 years back have been blacklisted and may soon proceed to being banished for good! Gas guzzling SUVs, generating stations using fossil fuels, logging, non renewable fuel, non renewable fishing methods – the list is endless. Incandescent lamps being another one of them.
Hence the entry of the energy saving compact fluorescent lamp (CFL) and compact fluorescent tube (CFT). While the fluorescent lamp was invented by PC Hewitt, the more modern CFL was the brainchild of Edward E Hammer who developed it at GE. The CFLs are fluorescent lamps and can be of various shapes and sizes. While some have the standard elongated tube light shape, there are a host of others with convoluted designs. To save on costs these CFL light bulbs are mostly designed to fit into existing incandescent light bulb fixtures. The advantages of the CFL light bulbs include:
- For the same amount of visible light emanated by an incandescent bulb, the CFL one uses far less power. The substantial savings in energy over the average life span between these two bulbs is a recorded fact.
- CFL bulbs have a longer life span as compared to incandescent ones, somewhere between 8 – 15 times that of the latter.
- While the CFL bulbs emanate a different spectrum of light compared to incandescent ones, the best ‘soft white’ CFLs emit colour similar to the latter.
- There is substantial savings in the greenhouse gases emitted between the 2 bulbs; up to 2000 times the weight in case of the CFL bulb.
The disadvantages are also there:
- The cost of a CFL bulb is substantially higher than the incandescent one.
- CFL light bulbs contain mercury (as do all fluorescent lamps), which has its own complications, especially in disposal.
- The ultraviolet and blue light radiation emitted by CFLs could be harmful for people suffering from specific types of skin disorders.
- The amount of light emitted in the later stages of a CFL light bulb can drop by 70%; however this is not a very noticeable change over the period of its life.
- The amount of time taken to reach full power is longer in the case of the CFL bulb
CFL bulbs can be used both in alternating and direct current and the basic parts are similar to that of its predecessor, the fluorescent lamps. There are some other modern lighting systems with which the CFL technology fares reasonably well. These include solid state lighting used in traffic lights as well as the LED lamps. There are also various modifications on the basic CFL light bulbs, which have cornered niche segments of the market; for example use of titanium dioxide coating on the outside of the se bulbs to kill bacteria and at the same time neutralise odours.
Overall the CFL light bulb can be considered a blessed invention!
Jul 24, 2009 at 07:06:29
All lights have their uses
However, it is ironic to ban ordinary light bulbs on environmental grounds (they don’t emit any gases – power stations might)
RE “CFL bulbs have a longer life span as compared to incandescent ones, somewhere between 8 – 15 times that of the latter”
“•There is substantial savings in the greenhouse gases emitted between the 2 bulbs; up to 2000 times the weight in case of the CFL bulb.”
These and other CFL advantages are not as great as stated
For a full list of reasons why supposed savings are incorrect see
http://www.ceolas.net/#li13x onwards
For example re lifespan
Rated lifespan is an issue:
“Part of the problem, it turns out, is that the “lifespan” of a CFL bulb has been artificially measured. International standards currently require a manufacturer to run the bulb in three hour cycles in the lab, only switching it on at the beginning and off at the end. In other words, the bulb burns for three hours straight with no interference.
In the real world, things are very different. Many householders, particularly in these energy-conscious times, switch on and off lights frequently as they enter and leave rooms. Many modern CFLs are not built to withstand short switching cycles (although Ecobulb [Ecospiral in the USA] claims theirs are). One recent study shows the lifespan of a CFL can be shortened by a massive 85% under normal domestic household use conditions. In other words, if the lab lifespan was 2,000 hours, you might get only 300 hours (four months) out of that CFL if you were unlucky. A 6,000 hour bulb (five years) would give you only 12 months or so of light before dying unceremoniously.” [my emphasis] -quote from http://www.thebriefingroom.com/archives/2008/08/mercury_in_cfls.html
The recent US Lawrence Livermore Lab study echoes the above, showing that for realistic household use where a light is used for an hour before being turned off, it suffers a 50% reduction in its rated lifetime. The loss to incandescent lifetimes was about 20%. Even worse, if the use of the light is only a half hour, the life of a CFL is reduced by 85%, whereas incandescent bulb lifetimes suffer only a 25% loss.
Meanwhile the official advice… “The cost effectiveness of turning fluorescent lights off to conserve energy is a bit more complicated. For most areas of the United States, a general rule-of-thumb for when to turn off a fluorescent light is if you leave a room for more than 15 minutes”, USA Dept of Energy, which goes on to list several situations when leaving lights on for longer may be better or worse.
The encouragement of cheap Chinese imports may have lowered quality, including lifespan.
German consumer testing October 2008 in any case showed lifespan problems (in whatever way multiyear lifespans are measured!). In the USA, the Lawrence Livermore Labs study concluded that the lifetime of the average CFL on the consumer market had a median life well short of its reputation or rating.
Loss of brightness (as you say) also reduces effective lifespan, US Department of Energy measurements have shown that a 1/4 of excellent (Energy Star) rated compact fluorescent lights do not reach rated brightness after less than half of their lifespan. Ordinary light bulbs simply cut out, at the end of their life.
Aug 11, 2009 at 06:35:00
Sometimes it’s really that simple, isn’t it? I feel a little stupid for not thinking of this myself/earlier, though.