The challenge is that artificial light impacts our environment as it often incorporates harmful and unnatural chemicals while using electricity, thus contributing to overall energy demand. Here at "U Can Bee Green" we've looked at the lighting options available considering the costs, energy demand and environmental impact of each. To do this we took what is currently the longest lasting bulb (or lamp) on the market; the light-emitting diode (LED) lamp. This lamp type currently lasts an estimated average of about 25,000 operating hours and so we factored in the amount of other lamp types that would be needed over these many hours So here's the breakdown ...
| Total Consumer Energy Use and Cost Over 25,000 Hours (~22 yrs*) | |||||
|---|---|---|---|---|---|
| Lamp Type | Lamps Used(3) | Lamp Power Usage (W)(3) | Total Energy (kWh) | Total Estimated Cost | |
| Low | High | ||||
| Incandescent | 22 | 60 | 1,500 | $ 206 | $ 228 |
| Halogen | 27 | 43 | 1,075 | $ 167 | $ 194 |
| CFL | 3 | 15 | 375 | $ 58 | $ 73 |
| LED | 1 | 12.5 | 313 | $ 71 | $ 91 |
Just this year the U.S. Department of Energy has published reports which summarize various studies of the full life-cycle impacts of LED lamps vs incandescent and CFL lamps. Below is a spider chart which is meant to be representative of the environmental impacts over the whole lifecycles of LED, CFL and incandescent lamps. The various aspects of impact to the environment are charted relative to the incandescent bulb which is represented by the perimeter.
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| U.S. Department of Enegy Office of Energy Efficiency and Renewable Energy (4) |
Compact Fluorescent Lamps (CFLs)
There have and continue to be concerns over the mercury (Hg) ending up in our landfills from CFLs. These lamps, like their basic fluorescent lamp cousins, contain small amounts of low pressure gaseous Hg. The Hg gas is a medium through which an arc of electricity then travels and causes the gas cloud to emit UV light. The coatings on the glass of these lamps absorb the UV light and subsequently emit light in the visible spectrum. As these lamps age, the Hg embeds itself in the glass walls until eventually there is not enough Hg gas for the lamp to arc. This is typically when the lamp is considered "burnt out". There are many places, including hardware stores that will take in and recycle expired lamps. A quick note on personal safety; in the case of lamp breakage it is recommended that the room be aired out and the glass be handled with gloves, placed into a plastic bag and disposed of.
Light-Emitting Diode (LED) Lamps
If you plan on keeping the same light for 20 years or more than this is a good option. However integrating LED lamps into trendy lighting arrangement may not be such a great idea for the environment as chances are that you will want to change it out long before the lamp expires. These lamp types also fall short in applications needing precise differentiation between colours as they do not score well on the colour rendering index (CRI) falling short of even fluorescent lights. What's interesting is that the International Commission on Illumination (CIE), which standardized the CRI, have recently stated that the CRI is no longer a recommended method of determining the quality of light emitted from LEDs, though they have yet to devise or recommend and alternative(1)(6). What seems uncertain is whether this is a change in attitude due to industry lobbying or if it is a change stemming from the scientific community? Whatever the case may be, LED light is not ideal if colour differentiation is critical. Another thing to keep in mind is that LED technology is still improving in terms of manufacturing and user operating costs. On the plus side this means it will get more energy efficient and cost effective. A word of caution however, as these improvements are realized, the resulting changes may increase the undesirable effects to the environment which is why it is so important that observers keep an eye on where the lead horse in the LED market takes us.
Here's the breakdown of the cost estimate for those really wanting to see it ...
| Lamp Type | Lamps Used (3) | Lamp Power Usage (3) | Estimated Purchase Cost | Operating Cost* | Total Cost | ||||
|---|---|---|---|---|---|---|---|---|---|
| Per Lamp | Lifetime | ||||||||
| Low | High | Low | High | Low | High | ||||
| Incand. | 22 | 60 | $ 0.50 | $ 1.50 | $ 11 | $ 33 | $ 195 | $ 206 | $ 228 |
| Halogen | 27 | 43 | $ 1.00 | $ 2.00 | $ 27 | $ 54 | $ 140 | $ 167 | $ 194 |
| CFL | 3 | 15 | $ 3.00 | $ 8.00 | $ 9 | $ 24 | $ 49 | $ 58 | $ 73 |
| LED | 1 | 12.5 | $ 30.00 | $ 50.00 | $ 30 | $ 50 | $ 41 | $ 71 | $ 91 |
Coming up ...... next month we turn back to transportation and take a dive into the rising tide of the electric car in search for pearls of truth in the murky depths of hype. In November we'll look into domestic water consumption.
Sources
(1) Dangol, R. (February 2011). Colour Rendering Index and colour rendering of LEDs. Master’s thesis, Aalto University Department of Electronics Lighting Unit. Retrieved August 2012 from http://lib.tkk.fi/Dipl/2011/urn100407.pdf
(2) Hydro Quebec (2011). Comparison of Electricity Prices in Major North American Cities. Retrieved July 2012 from http://www.hydroquebec.com/publications/en/comparison_prices/pdf/comp_2011_en.pdf
(3) Navigant Consulting Inc (August 2012). LIfe-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products; Part I: Review of the Life-Cycle Energy Consumption of Incandescent, Compact Fluorescent, and LED Lamps. U.S. Department of Energy Office of Energy Efficiency and Renewable Energy. Retrieved August 2012 from http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/2012_LED_Lifecycle_Report.pdf
(4) Pacific Northwest National Laborator; N14 Energy Limited (June 2012). Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products; Part II: LED Manufacturing and Performance. U.S. Department of Energy Office of Energy Efficiency and Renewable Energy. Retrieved August 2012 from http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/2012_led_lca-pt2.pdf
(5) U.S. Environmental Protection Agency: Energy Star (June 2009). Advanced Lighting Package for New Homes. Retrieved August 2012 from http://www.energystar.gov/ia/partners/manuf_res/ALP_Consumer_Brochure.pdf
(6) U.S. Department of Energy Office of Energy Efficiency and Renewable Energy (January 2008). Color Rendering Index and LEDs. Retrieved August 2012 from http://www.energystar.gov/ia/partners/prod_development/new_specs/downloads/integral_leds/Nexxus_Commercial_Lighting_2_IntegralLEDLampCommentsDraft2.pdf?9db4-88f7
