2 Overview Technology Background Technology Examples Energy Efficiency Opportunities Financials Example Questions
3 Importance of Lighting Light – the portion of electromagnetic radiation that is visible to the human eye, responsible for the sense of sight Lighting enables us to go about our lives, to work & play, and provides safety and security. The human eye has the ability to sense and adjust to a wide range of visual environments. Lighting professional must be aware of the relationships among lighting, productivity, human health, safety and security. Source: U.S. department of Energy, Energy Information Administration, Energy End use Intensities in Commercial Building, Sept. 1994. DOE/EIA-05555(94)/2
4 Importance of Lighting The ability of a light source to accurately give out the true color of objects is measured by the Color Rendering Index (CRI), which ranges between 0 and 100. The higher the CRI, the more natural and bright people and objects appear
5 How Much Light (Footcandles) Is Enough? Illuminating Engineering Society of North America (IESNA) recommends, as a good design practice, an average luminance ratio of no more than 3 to 1 for close objects and 10 to 1 for distant objects and outdoor applications. Luminance ratio is the ratio between the luminance of any two areas in the visual field.
6 Most Common Types of Lighting Fluorescent High Intensity Discharge Induction Lighting LED
7 Fluorescent Lighting A low-pressure mercury vapor confined in a glass tube, which is coated on the inside with a fluorescent material known as phosphor. The energized filament delivers electrons to the ionized inert gas within (usually argon), forming a plasma that conducts electricity.
8 Electronic vs. Magnetic Ballast The electronic ballast transforms the input power to a high frequency (20- 40KHz) before sending it to the lamp. This results in a higher system efficacy (about 30% compared to a magnetic ballast) due to lower lamp and ballast losses Source: G.E. Lighting
9 High Intensity Discharge (HID) For outdoor illumination, this light source is the most common lighting device on the market today. HID lamps have one drawback that may limit their use: a start-up delay from 5 to 20 minutes from the time they are switched on until they fully illuminate. Two particular types will be discussed: –Mercury Vapor –Metal Halide Source: Advanced lighting guidelines
10 Induction Lighting Combines the basic principles of electromagnetic induction and gas discharge to create a light bulb with no filament or electrodes. Rated at 100,000 hours or 25 years system life. Induction lighting systems include instant flicker-free starting and higher CRI with lower luminous depreciation.
11 Light-Emitting Diode (LED) LEDs are solid-state electronic devices that generate light via the transformation of electric energy to radiant energy within the crystalline structure of a semiconductor material. Long life: 50,000-100,000 hours Physically small: A single LED is about 5.6 mm.
12 Old Technologies – HID with Spun Aluminum Dome Basic grade spun aluminum domes typically only have 70 - 75% luminaire efficiency –Which means that 25-30% of the light from the lamp never gets out of the fixture –Which means 25-30% wasted light HPS only has 22 CRI –Perfect is 100 CRI, which daylight and incandescents have
13 Old Technologies – Standard MH Standard, also called probe start Not very good lumens per watt Bad lumen maintenance Very common 400W universal position probe start MH lamp is similar to mercury, lasting longer than rated 20,000 hours and getting dimmer and dimmer in the process California Title 20 eliminated standard MH in many applications
14 Which Technology is the Best? Induction LED MH – Pulse Start T5HO T8
15 Options – Avoid CFL Lamp efficacy is considerably worse than linear high performance fluorescent How good can a luminaire be with up to eight lamps in one cavity? Lamp replacement costs and maintenance costs can devour energy savings –The typical eight lamps can cost over $60 –Many lamps are rated for only 10,000-12,000 hours at three-hour cycles –Maintenance costs, including lift rental, hiring a maintenance firm, etc. can be expensive
16 Induction Less than 80 lumens per watt with generator Induction is a fluorescent without cathodes –So not much to wear out in lamps –So can get 100,000 hour rated lamp life –70-80% lumen maintenance at 70% of lamp life –60-70% of initial lumens at end of life Realistic system life is really 60,000-70,000 hours before significant maintenance is required for a group of fixtures
17 Induction Since induction will start down to -40 degrees F and C, can be very good in freezer applications Can work very well with occupancy sensors Much more expensive than T8 or T5HO high-bays
19 LED All previous lumens per watt were just light source without including fixture efficiency –LED fixtures are measured differently, including fixture losses Currently usually 50 - 75 lumens per watt out of the fixture –Some have 100 lumens per watt out of fixture –By sometime in 2011, may be 130 lumens per watt out of fixture 50,000 - 100,000 hour rated life while still providing 70% of initial lumens
20 LED Excellent with occupancy sensors Now too expensive for most applications, except –For some early adopters –For some freezer applications Efficacy & life improves as temperature gets colder Since LEDs are improving about 25% per year, lumens per watt, opportunities for cost effective retrofits in 3-5 years for fixture with modular LED panels
21 LED Also since pricing may be coming down about 20% per year, LED high-bays could become quite cost effective in a few years With rapid performance and pricing improvements of LEDs, the window of opportunity of induction is quickly closing –Induction is a mature technology, so only limited improvements are forecast
22 PS MH Two types of pulse start (PS) metal halide (MH) –Quartz, which has same 65-70 CRI as standard –Ceramic, which has 70-95 CRI & quite expensive Several advantages over standard or probe start MH –More initial lumens for same wattage –Better lumen depreciation –Better initial color consistency –Better color maintenance –Often longer life –Ceramic pulse start has much better CRI
23 Pulse-Start Metal Halide Although PS MH, especially the ceramic (often called CMH) is much better than probe or standard MH, PS MH does not measure up to other high performance options unless electronic ballasts are used 320-400W CMH lamp with an electronic ballast can provide 110 lumens per watt, and the CRI is better than anything else Electronic ballasts (250-450W PS MH) past five years –Still quite expensive, typically $150 just for the ballast –Do not really see the pricing coming down in the near term –Several manufacturers have gone out of business –Have been numerous problems –But there have been numerous successful projects –Some ballasts should not be used over 105 degrees F ambient
25 T5HO Reduced wattage F54THOs –Cost about $1- $2 more per lamp –Up to 93 initial lumens per watt including ballast –In the last two years, GE introduced their 51 watt that still has 5000 lumens, but shorter life –Earlier this year, Philips introduced their 49 watt, which still has 5000 lumens and has same life One advantage of T5HO hibays compared to T8 hibays –When you want as much light as a 400W pulse start MH lamp in a high performance dome, in a retrofit or new construction Can use a 2x4 hibay with 6 F54T5HO lamps Can also do it with 8 - 10 F32T8s, but –If 8 lamps, each reflector is only 3 wide in 4 long fixture –Or you need an 8 long fixture which costs more for parts and labor
26 T8 Fluorescent High performance T8 systems –Up to 102 initial lumens per watt including ballast –Long life, especially with program start ballasts –Very good with occupancy sensors with program start ballasts –Relatively inexpensive lamps –Can help minimize lamp and ballast types in a facility
27 T8 Ballasts Extra efficient ballasts consume 3-6 watts less than GEBs while providing the same amount of light While costing $1-$4 more initially, each can save $20- 50 in electricity over ballast life –About 15 years or 60,000 hour ballast life Most new fixtures come with GEBs, because they cost the least Some retrofitters are still using GEBs
30 Notes Vertical footcandles can often be more important than horizontal –With all technologies, high-bays can be designed to provide very good vertical fc –But many specific models do not Although there is a lot of competition with cheap fluorescent high- bays (down to $80 for some imports including 4 F54T5HOs), there are some very good high-bays, such as ones that have a 6 wide and 3 deep reflector for each T5HO lamp
31 Notes In some applications only HID, induction, LED and plasma lamp high-bays will fit –T8, T8VHO and T5HO high-bays can be too big With smaller size, it can be easier to make HID, induction, LED and plasma lamp high-bays work –Wet location –Sealed for other applications –Hold up to be hit by basket balls –Vandal resistant –Explosion proof
32 Financials One big problem with payback is that much of the benefit happens after the payback period: –For example, long life lamps Ask customers if they want the shortest payback or most money in their pocket in so many years. As with all first-level methods, simple payback does not consider the time value of money... Another problem with this method is that it fails to consider what happens after the investment is paid back...
33 Payback Examples Option A costs $100,000 and saves $50,000 per year, which is a 2- year payback, which would provide $650,000 over 15 years. Option B costs $300,000 and saves $100,000 per year, which is a 3- year payback, which would provide $1,200,000 over 15 years. Even factoring in the cost of money over time, option B is often the better solution.