University of Chicago
Type of paper: Thesis/Dissertation Chapter
Benefits of LED Lights Vs CFL
While the most walking spaces discourse regarding energy efficiency revolves around highly visible feature like solar panel, other efficiency technologies have the potential to reduce the amount of energy consumption significantly in walking space. With organizations such as Saudi Aramco where employees walk, jog, the ride bike and other different activities, the use of energy conservation can have meaningful environmental and monetary impacts. This report aims to provide Saudi Aramco’s board useful information about new technologies for energy and cost saving by making improvements to their Golf course. This report offers a starting point for considering energy efficiency improvements in the organization’s environment.
It has been projected that electricity for lighting consumes around 20% of the world’s power station’s production. Introducing energy efficient lighting to all our lighting needs will dramatically reduce the overall consumption of worldwide energy. Any small changes in our lighting use will produce substantial energy savings in the end. The high-energy use can be addressed by using cleaner energy sources, such as solar panels, and by using light sources that require less energy and produce the same levels of lighting. This report will propose an efficient lighting project to reduce the energy consumption of the lights used to illuminate the walkway around the Dhahran Golf Course.
The Walkway around the Dhahran Golf course is approximately 5.6 kilometers long. The walkway is used daily by Saudi Aramco employees to walk, jog, bike and other different activities. Most of this walkway’s use happens at night, after working hours, meaning that it needs to be well lit for the employees use. Currently, Compact Fluorescent (CFL) light bulbs that are fixed to poles all around the walkway illuminate the sidewalk. CFL light bulbs are considered to be more efficient than traditional Incandescent Light bulbs, having a service life of approximately 8000 hours compared to a maximum 1,000 hours for Incandescent light bulbs. This longer service life results in fewer light bulb replacements, but more efficient technologies exist.
For the Dhahran Golf Course walkway efficient lighting project, the team proposed the use of three innovative energy reducing technologies. The three techniques are, Light Emitting Diodes (LED), solar panels to power the LED’s, and a special material that uses energy gathered during the day to glow in dark. A brief summary of each technology will be given to better understand its use can contribute to providing more efficient lighting for the walkway.
Light Emitting Diodes (LED)
LED light bulbs emit light through the use of a semiconductor that releases light energy when an electrical current is passed through it. This way of producing light differs from CFL light bulbs, which pass energy through mercury vapor to generate UV light, which is then enthralled by a phosphor covering inside the lamp, causing it to glow. LED light bulbs have been in existence for some time now but were very expensive compared to Incandescent and CFL light bulbs. Over the last couple of years LED light bulb prices have dropped significantly, making them a more economically viable solution, especially when considering their very long service times. The table below details the differences between CFL and LED light bulbs.
Light Emitting Diodes (LEDs) Compact Fluorescents (CFLs)
Life Span (average) 50,000 hours 8,000 hours
Watts of electricity used 6 – 8 watts 13-15 watts
(Equivalent to 60 watt bulb). Annual Operating Cost $32.85/year $76.65/year
Contains the TOXIC Mercury NO. Yes-Mercury is highly toxic to your health and environment
Carbon Dioxide Emissions 451 pounds/year 1051 pounds/year
Sensitivity to low temperatures None Yes – may not work under-23 ºC or over 49 ºC
Sensitive to humidity No Yes
On/off Cycling (Switching on/off quickly) No Effect Yes – can reduce the lifespan drastically
Turns on instantly Sure No – takes time to warm up
Stability Highly Stable – LEDs can handle jarring and bumping Not highly stable – glass can break easily
Heath Emitted 3.4 btu’s/hour 30 btu’s/hour
Failure Modes Not typical Yes. May catch fire
As depicted from the above table using LEDs for lighting make both economic and environmental sense.
Solar panels are used to produce energy by converting sunlight directly into electricity. The electricity generated by solar panels is stored in batteries for later use. Just like LEDs, the costs of solar panels the past several years have been dropping, making them more economical. They have also become more efficient in converting a higher percentage of the light captured into electricity.
Glow in the Dark Paint/Stones
Consists of a luminescent material and synthetic resins that get excited by being exposed to daylight or a light source giving it an afterglow that initially is very radiant, then slowly dissipates as time passes by. This material provides a soft glowing light that only needs the sunlight during the day for it to produce light at night. This material can provide 10 hours of burning when exposed to only 2 hours of daily sunshine with a Luminescence Life of up to 20 years.
First the team obtained data set from the Saudi Aramco accounting department which contained a listing of cost energy spent. The data set also provided estimated energy use in lighting in Saudi Aramco. From here, the team was able to filter the data only for lighting around the Dhahran Golf course. With this data set, the group generated summary statistic to find distribution for energy consumption (mmBTUs). The purpose of defining statistical use was to estimate energy consumption for the Golf course as well as understanding the range of the golf course.
Next, the team then evaluated different technologies to gain energy saving potential. An early obstacle the team faced was how to estimate the impact of each technology on various places in the Golf course. To find a solution for this issue, the team conducted case studies and independent research to evaluate the other technologies. The team performed a systematic analysis of each of the techniques named above. Each technology was eluted based on: cost estimate for the project, difficulty of installation, a percentage expected efficiency gains, estimated payback periods and consistency of paybacks.
The figure that follows represents the consumption of energy (from 2013).
A case study analysis of the literatures suggested that the combination of all the technologies had a greater benefit-cost ratio than one and net present values hence indicating the benefits of energy saving brought by the technique. To prevent the high rise of energy consumption as suggested by the figure above, ultrasonic and infrared technology would be of greater benefit. These methods detect sound, heat, and motion, hence more efficient in spaces where people move more efficient. A more inventive technology such as this would increase the energy saving potential, but also may be unattractive to administration who have less control as to when the lights turn off in particular spaces. Despite their advantages, they remain much more costly to purchase than alternative lighting types.
This proposed design was first constructed by Daan Roosegaarde, a scene night painter, who developed a bycle path in Nueener, East of Eindhoven forming a part of the Van gogh cycle through Noord-Brabant in Netherlands. According to Roosegaarde, this proposed technology is “more gentle to the eye and surrounding environment” compared to other existing technologies (De zeen magazine, 2014, par 4).
Recommendation and plan of action
The solution I am proposing is a combination of the three technologies explained, LED lighting, Solar panels, and glow in the dark materials. First all the CFL lighting should be removed. CFL bulbs have a much shorter service life and have higher energy requirements. Due to the long-life and very low energy use, LED lights will be used instead. The LED lights will be powered by the proposed solar panels, making the solution self-reliant with no need to connect to the electrical power grid. In addition to the LED lights, the glowing material/paint that is placed on the walkway itself, will utilize the sunlight during the day to provide a glowing light at nighttime. With this combined solution, we will realize the following benefits:
Lower energy cost (no need to connect to the electrical grid)
Environmentally friendly solution
Self-reliant, all power is from the sunlight
Eliminate the need for CFL that contain hazardous mercury
Lower maintenance cost:
Less frequent bulb replacement, due to LED long service life and durability.
Energy efficiency avails an incredible opportunity for positive local, national and international impact. While organizations save money, the organization strain on the electrical system is relaxed, hence lowering of the global pollutant emission. Whatever the motivation, energy efficiency should be viewed as an opportunity to upgrade organizations. Saudi Aramco is encouraged to use this report as a supplemental resource in their decision process. After reading through the report, Saudi Aramco is heartening to learn further details about energy efficiency technologies of their interest.
Benefits of LED Lights Vs CFLs retrieved from: http://lifx.co/lighting101/advantages/led-vs-cfl/Comparison Chart: LED Lights vs. Incandescent Light Bulbs vs. CFLs. Retrieved from: http://www.designrecycleinc.com/led%20comp%20chart.htmlDe zeen magazine (2014). Daan Roosegaarde’s glowing Van gogh cycle path to open in the Netherlands. Retrieved from: http://www.dezeen.com/2014/11/12/daan-roosegaarde-van-gogh-bicycle-path-glowing-patterns-nuenen-netherlands/Pacific lamp Wholesale. Retrieved from: http://paclamp.com/news/light-bulb-moment-how-lighting-became-efficient-over-yearsPath V. G. Glowing lines Smart Highway. Retrieved from: https://www.studioroosegaarde.net/project/van-gogh-path/The History of the Light Bulb: http://energy.gov/articles/history-light-bulb