Saving Energy with Lighting: Methods, Applications and Strategies

Transcription

1 Saving Energy with Lighting: Methods, Applications and Strategies By: Omar A. Rivera C.L.E.P. AEE GE Specification Engineer To save or not to save is no longer the question; trying to convince someone that saving energy is a good idea is no longer the challenge. What everyone wants to know is what is the best way and where to start. Lighting is where to start because it requires a low investment cost to save energy when compared to HVAC and many other energy-saving options available within a facility. It also has a fast return on investment (ROI) and short payback period. To understand the best way to save energy, you need to understand the options available to you depending on the status of your existing facilities. There are three main categories for formulating energy-saving strategies: new construction, existing facilities less than 7 years old, and existing facilities 7 years old or more. Let s review the options and opportunities available. 1) NEW CONSTRUCTION The ideal status when considering energy savings is to be doing a new construction project, where you can install the latest and most effective technologies before the building opens. So what is the catch? Identifying the latest technologies can be a challenge. So here is a major rule of thumb to make sure you are on the right track: If you have been using the same technology for a number of years, you are probably leaving energy savings on the table. Technologies are coming out so fast that you cannot afford to maintain a routine or template specification process. You must question every specification you get and ask the simple question: Is there a more energy-saving version of this same fixture, lamp or ballast? Applying the latest energy-saving technologies will present the highest energy savings for a project at the lowest cost. Since it is new construction, you will get the energy-saving products at wholesale prices. And they ll be installed during construction, which is typically during normal business hours (as opposed to the higher cost of off-hours installation in a facility that s already in use).

2 Of course the project will save from day one of operation, and once the building is in use, maintenance personnel are more likely to replace with the same technologies than to question what was originally specified. In addition, a maintenance budget will be set to maintain these technologies as-is. If you specify the lower-cost, less efficient version, that is what will be used and budgeted for many years to come. Another big advantage of being in a new construction project is that you can apply the strengths of new technologies and design to the project around new concepts that reduce the amount of wattage per lighting fixture. Due to the high efficiency of lamps and ballasts today, instead of using 4 lamps per fixture you can design around 3 lamps or even 2 lamps per fixture, depending on the foot-candles required or recommended. This could lead to substantial savings that will be permanent within the facilities, avoiding future value engineering to less efficient products that cost less but consume much more. See Figure 1 for data. Figure 1 Commercial Recessed Troffer Lamp 81 LPW Ballast effic =70% 144(4) 114(3) watts 4 or 3xT12 System Lamp 88 LPW Ballast effic =85% High Frequency Better CRI 3xT8 Std IS System Lamp 98 LPW Ballast effic >90% Lower BF Fixture effic >85% Energy Saving Lamps High Efficiency Ballast.71BF PS w/sensors 3xT8 Systems Lamp > 100 LPW Ballast effic >92% Fixture effic >85% Fewer Lamps Longer Life UltraStart Watt Miser & HL 2L T5 Systems Lamp Type F34T12 F32T8 F32T8/HL F28T8 F32T8/HL F28W/T5/HL F28W/T5/HL F28T5/WM F28T5/WM Ballast Type 2 EM Std IS HE IS HE IS HE PS HE PS HE PS HE PS HE PS Lamp 12 hour start Number of Lamps Initial Lumens Ballast Factor Light Source Lumen (Mean) 7,054 7,022 6,803 6,035 6,273 6,664 5,505 6,337 5,235 Optical Efficiency (Parabolic) 73.0% 73.0% 73.0% 86.0% 86.0% 86.0% 86.0% 86.0% 86.0% Fixture Lumen Output (Mean) 5,149 5,126 4,966 5,190 5,395 5,731 4,735 5,449 4,502 Light Loss/Gain 0% -4% 1% 5% 11% -8% 6% -12% System Wattage Light Source LPW (Mean) Fixture LPW (Mean) % Energy Savings 26% 36% 43% 40% 39% 50% 41% 52% Whenever energy savings can be designed into the lighting system that is preferable. In the energy-saving industry we do make a distinction between what is called

3 permanent installation and temporary installation. If your design for energy savings can be altered simply by changing a lamp or bulb, then that is considered a temporary energy-saving application. There is no question that it will cost more to do a project with more efficient technologies. The real question is, Can the owner afford to pay the electrical bill if you don t specify a more efficient system? The largest share of the cost of a lighting system, 88%, is the electric bill. See Figure 2, the cost of light chart. Figure 2: What is the Cost of Light? Are you focusing in the right area to cut cost? As you can see, energy is the largest portion of the cost of a lighting system. 2) EXISTING FACILITIES Less than 7 years in operation As a lighting specification engineer, I am frequently called in to consult for existing buildings that are relatively new. Many times the owners or managers find themselves with very high-cost lighting systems and cannot understand why, since the facility was recently built. Well, the answer may be twofold. The cost of electricity has gone up, and those who specified the lighting systems may have been using the same spec for many years a spec that at one time was efficient when the cost of electricity was 20%- 30% less. In addition, as long as the design looks good, in many cases no one may think to question energy consumption. Unfortunately, this leaves thousands of dollars of potential energy savings on the table and a long-term problem for the owners. Here is the big problem and dilemma: You have a perfectly good lighting system that is relatively new, but it s killing you with high electrical bills. You must make a choice to make an investment to change the system all at once or do it piecemeal. If the building is closer to 5-7 years old, this will be less painful because it may be close to a major relamping anyway, and since you have to do that, you could take a more aggressive path of changing out ballasts or the entire fixtures.

4 3) EXISTING FACILITIES - 7 years in operation or more Many of the statements mentioned above apply to facilities that have been in use for more than 7 years, with the exception that older buildings have the largest potential to save energy. This is evident because several generations of better technologies have passed since the buildings have been in existence. Another reason that these facilities are the low-hanging fruit for energy conservation is because there is a large wattage gap between what was installed and what is available today. This produces a higher Return on Investment (ROI), making the proposal to change or retrofit existing lighting more attractive. Finally, in many cases the lighting systems themselves have been written off the books and no longer serve as depreciation against taxes. That being said, there is some limitation to saving energy with existing lighting systems if you plan to keep the existing lighting fixtures that were installed many years ago. Finding the right balance between saving energy and keeping people happy is instrumental and, some would say, an art. Here are some tips and strategies in finding that balance. A general rule of energy savings in existing facilities Almost every lamp and ballast in the marketplace today has an energy-saving replacement. Finding the threshold for allowable change and budget is key before recommending an energy-saving system. Remember, your client may have half a dozen to a dozen contractors working in its facilities at night and on the weekends to make these changes. Understanding what your client is really willing to put up with means understanding the needs of their staff as well. Retrofits Some existing facilities are perfect for what is called a retrofit, which means that you can use the existing housing of the current lighting system. This is a lower-cost method of getting substantial energy savings. Some retrofits are as easy as changing a light bulb. The more sophisticated versions can also entail the changing of the ballast within the fixture, which may involve hiring contractors who can do it afterhours with the least interference in the day-to-day business. Swap out In some cases it makes more sense to change technologies all together, meaning to take down the entire fixture and install a new updated fixture. This could be an easy process if you have a qualified electrician who can advise you of the additional cost of the electrical connection involved in changing from one fixture to another. The cost of doing this will initially be higher than the cost of a retrofit, due to the added cost of the new fixture and the substantially higher cost of labor. On the upside you can go ahead and install the most advanced technologies in lighting and benefit from other aspects of that system such as non-glare indirect lighting.

5 Getting your ducks in line Have you heard of the old joke about how many people does it take to change a light bulb? Well, in the case of doing a retrofit or a swap out, a lighting system can involve many people to get an approval. So make sure you understand who is involved in the approval process. This can be your biggest hurdle when it comes to energy savings. Make sure you get all the approvals for design, color, and budget. Note Before we move on I want to set a basis for comparing one system against another. All strategies recommended in the rest of this article will be based on lamp and ballast energy consumption combined, better known as system watts. Due to the advent of the electronic ballast and its growing efficiencies, it would be a big mistake not to include ballast in part of your decision-making about what products can help you reduce the most energy consumption. MORE ENERGY-SAVING STRATEGIES Light Levels and Color Rendering Index (CRI) The first step when considering changing a lighting system is to understand the amount of light the current lighting system is producing, so that you recommend an energy-saving replacement of the system that is equal in light levels or better, as a general rule. There are some exceptions, such as where the original lighting levels are too high, and that may warrant lower levels of light. Or the task has changed within the workspace and lower light levels are better, or task lighting has been added and less overhead lighting is needed. How to determine proper light levels when retrofitting a lighting system When retrofitting a lighting system, begin by determining the current light levels to get a baseline for comparison. Let s walk through an example: 1) First, get the lamp and ballast description. Use a catalog or website to determine the mean lumens of the lamp and the ballast factor of the ballast. (Mean lumen rating is what is used as an average light level of a lamp). 2) Take the mean lumens and multiply it by the ballast factor as a percentage. For example, if the mean lumens of an F34T12CW is 2,280 lumens and the ballast factor is.90, then the current lighting system lumens is 90% of 2,280, or 2,052. 3) Now let s say you are going to retrofit to a T8 system and the F28T8/SP41/UMX/ECO has a mean lumens of 2660 and has a ballast factor of 87. The lumens will be 87% of 2660, or 2314, which is 262 lumens more per lamp than the current system. 4) You multiply 262 times the number of lamps, in this case 4, which is 1048 lumens more than the current system. This could be too bright and people

6 could complain. The solution could be to specify a low ballast factor, such as.77. That would be more in line with current system, providing initial light levels of 2048 per lamp. It is important not to overdo the energy conservation effort, meaning that if you reduce the light levels too low with the purpose of saving energy, you will have a negative experience within that facility and the personnel will rebel against any other recommendations to save energy. That is why it is important to have a clear understanding of what light levels are needed before recommending new energysaving solutions. Ballast factor can be used as a tool to resolve lighting issues without having to change the fixture. Please see below the many ballast factors recently made available. Figure 3 Ballast Factor Effect Light Output 135 % 130 % 125 % 120 % 115 % 110 % 105 % F28T8 on 1.15 BF H = High Light, Hi -Bay, HO replacement F28T8 on 1.0 BF N + = Less Lamps 2385 lumens 100 % 95 % 90 % 85% 80% 75% 70% 65% F28T8 on.87 BF N = New Fixtures F34CW on.9 BF = 2385 lumens F28T8 on.77 BF L = Low Energy F28T8 on.71 BF PS -L = Low Energy F28T8 on.60 BF XL extra Low, Lower Light Level How the Color Rendering Index (CRI) of the lamp source can help improve energy conservation The following Color Rendering Index (CRI) table of different lighting technologies shows CRI levels. The best CRI you can obtain is 100, and the higher the CRI is, the better the human eye can see objects. If you have very high lumen light sources with a low level CRI, you need more lighting to compensate, and vice versa.

7 Figure 4 Lamp CRI and Color Comparison Data Standard Deluxe SP 700 Series SPX 800 Series Chroma 75 (92) Tri-Phosphor Colors HID DEGREES KELVIN Daylight (75) * SP65 (78) Daylight MH (90) Chroma 50 (90) SP50 (78) SPX50 (86) Lite White Lite White (49) Deluxe (70) CW (62) Cool White SP41 (78) SPX41 (86) CMH (90+) Deluxe (89) MVR (65-70) White (60) SP35 (78) SPX35 (86) Mercury DX (50) WW (52) WW DX (77) SP30 (78) MVR/SP30, MXR (70) SPX30 (86) CMH (80+) INCANDESCENT * (100) **82 for T8/WM SPX27 (82) LU/DX (65) LU (22) ( ) = Color Rendering Index (Ra) Values = Colors Affected By U.S. Federal Energy Legislation LPS (0) = Typical Range of Color s for Incandescent Lamps Included for Reference Only Using a higher CRI (color-rendering index) can also help you reach your energysaving goals, or provide a greater sense of comfort in reducing lighting design wattage per fixture. Having a high level of lumens does not mean your eyes can identify and recognize objects better. Poor CRI lighting sources, such as a 400 watt (system watts of 458) HPS with a CRI of 22, can be replaced by a 336 watt fluorescent 6 lamp T5 system with a CRI of 85. How to determine the proper replacement lighting systems For any type of facility, if you want to update a standard specification to a more energy-efficient one, you should make a side-by-side comparison as follows: 1) Compare initial lumens of the specified products to initial lumens of the more energy-efficient products. 2) Also compare mean lumens to mean lumens

8 Note: Many of the energy-saving lamps might start out with less lumens than a non-energy-saving lamp, but after 6 months to a year, the energy-saving lamp is at equal lumens and provides more light throughout the life of the lamp -- while the non-energy-saving lamp light level continues to decline and provides less lumens, therefore becoming increasingly less efficient. See Figure 3 (above) for comparison. 3) Compare system watts Note: In comparing systems, you can find out how much you would save in energy costs by running an energy-saving estimator. Many clients will consider anything that has an ROI of less than two years a very acceptable investment. It is also advisable to have the lighting designer run a new photometric study with the energy-saving lamps and ballast. In many cases, due to the fact that many of the newer lamps are so efficient, you may be able to reduce the amount of fixtures specified for the project -- which in turn can help you save even more energy. See Figure 5 for a simple cost of light comparison. Cost of Lighting Figure 5

9 RECOMMENDATIONS BY TECHNOLOGY TYPE Halogen Technologies The latest innovation in halogen is infrared halogen lamps, such as GE s Halogen HIR Plus lamps. Many recess lighting and track lighting systems that are installed are using regular halogen parabolic reflector lamps. Substantial energy reduction can be obtained by substituting with the HIR Plus lamps. Currently, for instance, you can take a 90-watt halogen down to a 67-watt halogen HIR Plus lamp and get more light output. You can also find this technology available in MR-16 lamps 12volts. It is also a good idea to change out regular incandescent bulbs to standard halogens, because they can produce similar light levels for less wattage. Less wattage produces less heat, and less heat reduces HVAC demand, and therefore reduces energy consumption in warmer months. Bonus: Halogen HIR Plus lamps have double the life of standard halogen lamps, giving you a more efficient solution. See Figure 6 for information on GE s Halogen HIR lamps. Figure 6 GE Halogen HIR Plus PAR HIR PC/Description 48PAR/HIR+/SP10 48PAR/HIR+/FL25 67PAR/HIR+ 67PAR/HIR+/FL25 45PAR/HIR+/SP10 45PAR/HIR+/FL25 60PAR/HIR+/SP10 60PAR/HIR+/FL25 HIR Plus Filament Tube Coating Coil

10 Metal Halide (MH) Technologies~ Pulse Start There have been two major energy efficient MH technology developments in the marketplace: pulse start and ceramic metal halide. Pulse-start technology is a lamp and ballast enhancement over original metal halide. This technology has the benefit of producing more lumens per watt (LPW), making a more efficient metal halide application. This allows you to specify a lower watt lamp and ballast combination. For instance: One of the most commonly specified MH lamps in the marketplace is the 400- watt mogul-based lamp that produces 36,000 initial lumens and 23,500 mean lumens in a vertical position. In contrast, a 350 pulse-start lamp produces 37,000 initial lumens and 27,500 mean lumens, also in a vertical position. Not only is it brighter to begin with, it also stays brighter through its rated life. In lighting we talk about lumens per watt to judge efficiencies, just as with cars we talk about miles per gallon to judge efficiencies. In this case, the 400 watt MH has 90 lumens per watt, but the 350 watt MHPS has 106 lumens per watt -- making it 12% more efficient on top of consuming less energy. As for system watts, the 400-watt MH is really a 458-watt system when you include the ballast. A 350-watt is really a 396-watt system. Thus the pulse-start lamp in the example above is 62 system watts less than the MH system, and as you start to multiple these out over the amount of fixtures in the facility the difference becomes substantial. Note: To use a pulse-start lamp in an existing Metal Halide fixture, you must also change the ballast to a pulse-start type of ballast or Electronic HID ballast. Tip: If you use a metal halide electronic ballast with the 350 MHPS lamp, you could save an additional 20 watts, for a total system watts of 276, versus the 458 of the 400 watt MH lamp system Ceramic Metal Halide Technology Ceramic Metal Halide, or CMH, lamps are the latest improvement in metal halide technologies. There are several advantages to this fast-improving technology since it arrived in the marketplace. When it comes to energy conservation this technology is a leader because of the lumens per watt that it produces. Let s do a quick comparison: A Halogen 120 watt PAR38 has 1900 lumens, or 15.8 LPW (lumens per watt). In contrast, a 39 watt GE CMH MR16 has 2100 lumens with 53.8 LPW -- that is a 75% more efficient light source. It has longer life of 12,000 hours, compared to 2,500 hours of regular halogen lamp or 4,200 hours of GE s Halogen HIR.

11 Ceramic Metal Halide lamps are most efficient on electric ballasts, but will work on pulse-start ballasts. A windfall benefit is that they can achieve very high CRI of 80 to 92, depending on the wattage of the lamp. They also come in many of the same bulb shapes as halogen, allowing for these lamps to come in smaller, more designoriented type fixtures. GE s CMH lamp comes in 20 to 400 wattages. Tip: If you have existing halogen track lighting in your facility, you could retrofit the fixture to GE CMH lamps by simply ordering new track fixtures and using the same track rail. Another windfall benefit of using CMH lamps is that you are using less wattage per foot than halogen lamps. Therefore, you could increase the amount of fixtures on the track. Maintenance will be reduced in most cases by 50%, due to the more than double the life in most cases compared to halogen lamps. Bonus: Using CMH lamp sources may help you achieve LEED, ASHRAE and ENERGY STAR energy standards. The lower wattage will also help reduce your HVAC consumption and therefore save energy. Linear Fluorescent Technologies Most people think of linear fluorescent technology when thinking of energy conservation. Fluorescent lamps save energy over incandescent lamps and have only continued to improve in efficiencies over the past generations. The linear fluorescent lamp is the most commonly used light source in the commercial and industrial market segment. It would take about 5 to 6 times the amount of incandescent bulbs as fluorescent lamps to light up a big box store. For indoor applications fluorescent lamps continue to be the workhorses of the lighting industry. In today s electronic age you cannot give all the credit for energy efficiency to the lamp by itself. The fluorescent lamp works together with the fluorescent electronic ballast in combination to reduce energy. As a matter of fact, the electronic ballast is the smart one of the two. So as we discuss strategies, tips and details for fluorescent lighting, it will be with a system approach of both the lamp and ballast. To begin to understand the potential that you may have to save additional energy with newly specified or existing fluorescent fixtures, you need to identify what type of ballast and lamp you are working with currently. These lamps are identified by the lamp diameter, in measurements of 1/8 of an inch. So when someone says, I have a T12 lamp, what he or she means is that they have a lamp that is 1½ inches diameter. Why is it important to understand what lamp you have when it comes to energy conservation? This information will tell you what ballast the lamp will use and if it is interchangeable with other more efficient lighting systems. Allow me to share with you guidelines on fluorescent retrofitting.

12 Linear fluorescent rules of engagement for retrofit In a T12 facility - If you have T12 lamps with magnetic ballasts in your facility, you have a high potential for energy conservation of 35-45% by changing to a T8 electronic lighting system. The T8 will fit into the current fixture sockets and you may use the current fixture, but the T12 ballast must be changed out because it uses an old magnetic ballast technology that is not compatible with the T8 lamp. In a T8 facility - Many people will very proudly say that they have a T8 facility and feel that they are the most efficient they can be. That was very true for a long time, but better lamps and ballast have come out in the last 5 to 7 years that can save up to 15% over the original F32T8. More strategies for saving with linear fluorescents Here are some ways to save energy if you already have T8 s on-site: Just change that lamp. All of us have routines and habits that make us feel safe. We exercise the old saying, If it s not broken why change it? The easiest energysaving strategy is to simply replace a less efficient lamp with one that s more efficient -- but it seems to be very hard to implement that strategy. Here s a solution: Change your purchasing habits. Just stop buying standard F32T8 lamps and start buying the more efficient F28T8 lamp. This act will save you 2-3 watts per lamp and provide you 10,000 hours more life. That is a 10% energy savings, without disturbing your current work environment. All you have to do is order your next box of lamps F28T8. They fit in the same fixture and they come in the same colors; actually many people probably cannot tell the difference without looking at the label. It is recommended that you do this all at once to get the total benefit across the entire facilities, but you could do this as the lamp burns out. The savings might not seem like a lot, but in a facility with 2000 fixtures, it begins to add up. See Figure 7. Figure 7 - Energy Savings Comparison Chart (Calculations based on 5,000 hours of annual 10 cents per kilowatt-hour).

13 4 lamp System F34T12 Old F32T8 F28T8, Ultra Wattage Savings % 23% 41% Lamp Lumens 2750 / / / 2585 Ballast Factor End of life light 78% 86% old T8s 93% EOL Lumens CRI Annual Cost $74 $57 $43.50

14 New to lighting ~ No matter what length or type of fluorescent lamps you may have, an energy-saving replacement exists today. Tip: Almost every T8 and T5 lamp has an energy-saving version. A great way to see if you are leaving energy savings on the table is to find out what is equal to what you have in a more efficient version. Any GE Specification Engineer will gladly provide a list that matches what you are currently using to a more efficient lamp. Change out both the lamp and ballast. The next step in energy conservation with linear fluorescents is to change the ballast and the lamp. You could do this in a replacement mode but it would take you years to complete this project. That s why most facilities consider doing what is called a retrofit project, which entails hiring an Energy Service Company. or ESCO. This type of company does this full time and knows the nuances of the work; and there are many. They specialize in this kind of work, have adjusted down their rates due to volume of work, and are used to working after hours without charging extra. That being said, it is a best practice to change the lamp and the ballast to achieve maximum energy savings. For example, if you retrofit a standard F32T8 3-lamp fixture that had the older electronic ballast version, the system watts would be 87 watts. In comparison, with new high efficient electronic ballast and an F28T8 you can save 16 watts per fixture -- which equates to a 21% energy savings. This new T8 lighting combination would be at 71 system watts. Bonus: You also pull out 16 watts per fixture of heat (out of the building), which reduces your HVAC demand in the warmer months, therefore saving energy on your HVAC as a bonus. You could specify that the ballast be Ultra cool running ballast certified, giving you the maximum heat reduction within your facilities. Bonus: F28T8XL lamps are rated 30,000 hours at 12 hour starts, which is 10,000 hours more than an F32T8. If your facility leaves the light on for 18 hours a day, 5 days a week, that would be 3,960 hours a year. You would add up to two more years plus of lamp life. That means you would have fewer lamps used, fewer you would have to buy, and fewer lamps you d have to recycle. Hidden energy savings: in over-lit buildings Many buildings have been retrofitted at least once. Buildings that originally were a T12 building and were retrofitted to a T8 system may be 15 to 20% over-lit, meaning that the fixtures are producing more light than needed and more than the facility was originally intended to have. For instance, a cool white T12 lamp out of the box has 2,650 initial lumens, or (since most designers use mean lumens as the basis of design) 2,280 mean lumens. If that lamp is retrofitted with an F32T8, which has initial lumens of 2,800 and mean lumens of 2,660 lumens, that change produces 15% more light than the workspace originally

15 had. Now throw in the fact that the CRI of a low-end T8 lamp is 78, versus the T12 CRI of 60; this is a 24% increase in quality of light. In addition to that, due to the poor lumen maintenance of the T12 lamp, most fixtures were specified with 3 and 4 lamps; that magnifies this concept of over-lighting a facility. With the advent of having a computer at everyone s desk and putting everyone into a cubical, other light sources became available to many people. The most prominent is the task light because overhead cabinets create a shadow right over the desk. I would say a vast majority of office spaces and buildings have this profile. To find those hidden energy savings you need to find out how many foot-candles on average task level is used at the desk level. The old standard for office work was 55 foot-candles; the new IES recommend foot-candles -- a 40% reduction. So if this type of work space is at foot-candles, you have a lot of room to reduce light levels. Of course each facility is different, and personal and work tasks are different. So you will have to gather some empirical evidence to substantiate your finds or bring in a third party to do so. Here are two methods to reduce energy by lowering lighting output and watts per fixture. I would highly recommend that you select several small test areas that would provide honest feedback. The best feedback you can get is if you lower the lighting and nobody notices the difference. This will tell you that the area was over-lit and you were wasting a lot of energy. Method # 1 - Using a lower lumen T8 lamp that consumes less energy is an easy way to approach this. A standard F32T8 lamp on a 3-lamp fixture might provide about 7,308 lumens and consume 81 watts. An F32T8/25W on a 3-lamp fixture might provide about 6,264 initial lumens and only consume 66 watts, a 19% energy savings -- by just changing the lamp. Method # 2 - Complete lamp and ballast retrofit approach. If you have a 4-lamp F32T8 fixture that consumes 114 watts and 9744 lumens, you can afford to reduce the light level even more. Retrofit to an F28T8 lamp and a ballast with (L) lower power ballast factor of.77. That would provide you system watts of 86 watts and initial light levels of 8,470 lumens -- a savings of 28 watts per fixture and a 25% reduction in energy consumption Retrofit to a F32T8/25W lamp and ballast with lower power ballast factor of.77. That would provide system watts of 78 watts and initial light levels of 7,393 lumens -- a savings of 36 watts per fixture and a 32% reduction in energy consumption Compact Fluorescent Lamps~ Plug-in and Screw-based. Plug-in compact fluorescent lamps have been in the marketplace for quite a while and seem to be frequently specified in many types of applications. Each

16 plug-in has a unique base and doesn t lend itself to many retrofit applications unless you purchase a retrofit kit or adapter. The best application of compact fluorescent plug-in lamps is when they are specified instead of less efficient light sources such as incandescent. The four-pin plug-in lamps are the electronic version of this technology, which allows them to be dimmed using the appropriate ballast. Dimming any light source reduces the amount of watts consumed, therefore allowing for some energy savings. These lamps in their own right are very efficient and should always be considered when selecting lighting for a project. Screw-based compact fluorescent lamps are the opposite of plug-in type lamps; they were made to retrofit millions of incandescent sockets in the world. As a rule of thumb, they consume about 75% less watts while producing the similar light level of the lamps they are replacing. There are low-cost retrofit solutions for many applications because no electrical work has to be done to install these lamps. Pitfalls do exist and can be avoided by knowing the proper application. Heat is this technology s worst enemy, so don t place inside fixtures where heat will accumulate. By placing them inside you will overheat the electronic ballast. As a rule of thumb, if you are replacing an incandescent reflector, use compact fluorescent reflectors of the same size and so on. Find out if the compact fluorescent was made to be in the base-up position. This position is the most susceptible to heat overload and should only be used when the compact fluorescent has been tested to handle heat in that position. The U.S. EPA has set a standard of energy efficiency for these products and those who meet this higher standard are allowed to claim that they are an approved ENERGY STAR product. Sensors: Saving with automated devices that control lighting systems They say the best way to save energy in any environment is to not use energy. The second best way to save energy is to not to use energy when we don t need it. If we were all robots and were programmed to turn the lights off when leaving an area, that would save enormous amounts of energy. Many of us are very conscious about the wasting of energy, especially if we are financially responsible for the use of that energy. At work or at public places this concern seems to be, for most people, someone else s responsibility. So, we leave the light on. Or we are concerned for safety and do not want to leave an area dark for the next person coming in that area. Sensors that can tell if someone is in the room seem to solve this decision-making process for all of us. If a sensor does sense that the area is not in use, it applies the most effective rule of energy conservation by turning the light off. Of course as people come back to the room the sensor turns the light back on.

17 So if this is such a great technology why isn t everybody using sensors? Well, many facilities are using them and more will begin to use them to meet building and electrical codes. Most facilities are just beginning to install them and understand where to use them due to limitations of the technology, such as the sensor not being able to sense around corners or through partitions. Security and safety seem to be the biggest reasons why people shy away from sensors. Nobody wants to be the last person working late and be in area where all the lights are out, or be in area that has a physical barrier such that the sensor can t sense your presence, and turns the light off. Sensors have their place and are very effective in certain applications. For instance: Single offices that have four walls mean you can install a sensor in the right position that will always sense the person in that office. Bathrooms are a common place where sensors can be effective. My recommendation is that you only wire to the sensor 90% of light, leaving 10% of the lighting always on. In addition, many bathrooms have L- or H-shaped floor plans and sensors can t go around corners. Be careful to make sure that the sensor has line of vision of the whole area or you might have to place more than one sensor per location. Closets, janitor rooms and storage areas, warehouses or any areas that are not used very frequently are prime targets for sensors. You would be amazed how many rooms are used once a week but will have the light on the whole time. Meeting rooms, classrooms and conference rooms are also great areas for sensors, because nobody owns the space per se and nobody takes the responsibility to turn off the lights. These rooms also can be large and there can be many rooms in a facility, so the savings could really add up. Caution: Be careful in placing sensors in Electrical, HVAC rooms or any room where trades work has to be done. These places have many barriers that cut down the effectiveness of the sensors and may leave a worker in the DARK while doing dangerous work inside a piece of equipment. I would lean on the side of a timer switch that would turn the off the lights at a time selected by the worker himself. Most people will select more time than they need. At least you know that the light will turn off after a certain time even if they leave and forget to turn the light off. To implement an effective sensor program, you should know that the frequent turning off of any lamp will have a detrimental effect on the life of the lamp unless you use the proper ballast. The majority of ballasts in the marketplace today are called as a group instant-start ballasts. If you have instant-start ballast in your

18 facility and apply a sensor to it, there will be some harmful effects on the life of the lamp. How much harm is determined by how many times a day you turn off and on that lamp. NEMA, the National Electrical Manufacturers Association, recommends that you use program-start ballasts if you are going to have more than 5 off and on events a day. Keeping track of how many times lights are turned on and off in a day can be pretty complex. So as a rule of thumb it is recommended that wherever you use a sensor, it would be wise to use program-start ballast to maintain lamp life rating. TAKING THE FIRST STEP IS THE HARDEST A standard lighting specification is often used only because of lack of awareness of more efficient products or a routine habitual specification. Achieving energy savings can be a matter of challenging yourself and others to break the mold on what has been specified in the past. There are many ways to save energy, but the first step is to want to make it happen. I hope this paper was informative and has helped you to learn more about potential energy savings in your facility and how to evaluate your systems.