What has been the experience of those who have installed HID plasma luminaires?
NLPIP interviewed an individual associated with each of four plasma lighting demonstrations and pilot studies, detailed below. These applications were either mentioned in the popular press, were funded by governmental or private agencies, or were brought to NLPIP's attention from specifiers who participated in the 2012 survey (as discussed in the section "What are the claimed and perceived advantages of plasma lighting systems?").
Scottsburg Municipal Electric Utility, Scottsburg, Indiana (2009 - 2011)
- Scottsburg Municipal Electric Utility partnered with Stray Light Optical Technologies to replace 56 existing 400 W HPS streetlights with 40 streetlights containing plasma lighting systems, in a pilot project funded by the American Public Power Association (APPA) Demonstration of Energy and Efficiency (DEED) program (Rea 2011). A 51% reduction in total lighting power was accompanied by a 68% decrease in average illuminance.
- During the pilot project, many of the 40 installed plasma streetlights failed and were repeatedly replaced over the 20-month observation period (Rea 2011). One-third of the plasma streetlights did not start when the ambient temperature was less than approximately 15įF. Most of the 40 plasma streetlights failed due to a faulty component in the power supply. In addition, most of the 40 plasma streetlights had incompatible gaskets that caused significant off-gassing. The off-gassing created an opaque film on the plasma arc tube, which led to increased lumen depreciation, discoloration of the arc tube, and failure. All three quality issues were addressed by the luminaire manufacturer under warranty.
- Despite these issues, Scottsburg Municipal Electric Utility has since continued to replace more than 300 HPS streetlights with plasma streetlights. There have been no failures in these replacements due to cold weather (ambient temperature less than approximately 15įF) (Jim Binkley, Scottsburg Municipal Electric Utility, personal communication, 2013).
- Scottsburg Municipal Electric Utility plans to replace up to 527 HPS streetlights with plasma streetlights in total. They are satisfied with the way the manufacturer has replaced the products as needed (Jim Binkley, Scottsburg Municipal Electric Utility, personal communication, 2013).
Sacramento Municipal Utility District, Sacramento, California (2011)
- Sacramento Municipal Utility District (SMUD) published a technology brief on light-emitting plasma in December 2011 (SMUD 2011). One demonstration project that received a Customer Advanced Technologies program research grant is mentioned in this report. At this site, LUXIM wall-mounted luminaires replaced existing MH floodlights. SMUD also provided NLPIP with information about two other demonstration sites that received Customer Advanced Technologies program research grants. In one of the demonstration sites, LUXIM wall-mounted luminaires replaced existing MH floodlights. At the other demonstration site, LUXIM area lighting luminaires replaced existing HPS area lighting luminaires. In all three demonstration sites, uniformity ratios improved under the plasma luminaires.
- At one of the wall-mounted lighting demonstration sites, average light levels decreased by approximately 30% while total lighting power decreased by approximately 50%. Although there were multiple failures at this location with earlier generations of the plasma luminaires, there have been no failures at this location since November 2012. At the other wall-mounted lighting demonstration site, light levels increased even though total lighting power decreased. Although there were failures at this site, this customer plans to install more plasma luminaires and a wireless control system by December 2013 (Dave Bisbee, SMUD, personal communication, 2013).
- In the area lighting demonstration site, the decrease in total lighting power was accompanied by an even larger decrease in light level. At this site, there were multiple failures and this customer has replaced the plasma area lights with LED luminaires (Dave Bisbee, SMUD, personal communication, 2013).
- SMUD indicated that there was an average failure rate of 25% across the three sites with multiple generations of luminaires and noted that the manufacturer had been replacing luminaires as needed. In some cases, the luminaire replacement was not due to outright failure but due to a green color shift after 8000 h of use (Dave Bisbee, SMUD, personal communication, 2013).
Ports America, Oakland, California and Newark, New Jersey (2010 - 2012)
- Ports America is the largest terminal operator in the U.S., operating in more than 42 ports and 80 locations nationwide. Most terminal lighting is provided by 1000 W HPS high-mast luminaires (1280 W input power per luminaire) using poles that are 80 to 150 ft (24 to 46 m) in height, spaced 250 to 400 ft (76 to 120 m) apart with 8 to 12 luminaires on each pole. Some of the marine terminals are at the end of the utility grid distribution lines and power supply fluctuations are an ongoing issue.
- Ports America is evaluating lighting upgrades in order to reduce sky glow; meet OSHA standards of 5 footcandles (54 lux) average in work areas; reduce its energy use; use existing poles; augment safety and reduce maintenance costs. The HPS lamps and ballasts need to be replaced annually because of power quality issues. The HPS luminaires also have a high energy cost of $818 per luminaire per year.
- Ports America, along with the Pacific Gas and Electric Company (PG&E), evaluated successive generations of plasma luminaires for the past two years (Ward 2012, 2013 and personal communication, 2013; Douglass et al. 2013).
- In this demonstration, 12 new 1000 W HPS luminaires were replaced with twelve, ten, or eight 560 W high mast plasma luminaires from Bright Light Systems. The plasma luminaires required less power but also had lower average horizontal illuminance by approximately the same ratio (Douglass et al. 2013; Ward 2013). The measured uniformity was better under the plasma luminaires (Douglass et al. 2013; Ward 2013), and the plasma luminaires produced higher light levels at some key locations, such as the wharf "bull rail" (Thomas Ward, personal communication, 2013).
- The plasma luminaires were able to be individually dimmed and switched in groups, although the 50% dimming setpoint produced approximately 35% of the full light output and used approximately 60% of the full power demand (Douglass et al. 2013).
- Ports America investigated the potential visual benefits of white light (Ward 2012; Douglass et al. 2013). However, light levels at these sites were high enough that there would be very little, if any, improvement in peripheral visual performance due to spectral effects (ASSIST 2009; Douglass et al. 2013). The improved color rendering capabilities of the plasma luminaires make it easier for workers to see ground striping, to differentiate container edges, and to read container markings, and the workers prefer the "whiter" light source (Thomas Ward, personal communication, 2013). In some situations, there was a direct view of the plasma luminaires and glare was an issue. Ports America is considering adjusting the task locations to overcome this problem (Thomas Ward, personal communication, 2013).
- Over the course of the evaluation, Ports America found that the plasma luminaires were also sensitive to power supply fluctuations and the luminaires were replaced under warranty. Recent generations of the luminaire include updated electronics that have stabilized the luminaire's output (Thomas Ward, personal communication, 2013). Ports America believes that the Bright Light Systems luminaires produce less sky glow, compared to the base case, likely due to luminaire shielding and lower light levels.
- Ports America has determined that the plasma luminaires meet the OSHA illumination criteria (Thomas Ward, personal communication, 2013). Ports America has determined that the plasma luminaires are suitable for the Outer Harbor installation, and is working with the manufacturer to use the plasma luminaires in other port installations. Ports America is also evaluating LED systems for this application, but has found the proposed luminaires to be too heavy to be suitable (Thomas Ward, personal communication, 2013).
Hydro One, Leamington, Ontario, Canada (2010)
Interview summary (David Forgione, Hydro One, personal communication, 2013)
- Hydro One, a utility in Ontario Canada, incentivized the replacement of 370 existing 1000 W HPS luminaires with 295 W Plasmalyte plasma luminaires on a one-for-one basis for a greenhouse application. The luminaires were incentivized under the Ontario Power Authority saveONenergy RETROFIT program administered by Hydro One's conservation demand management department.
- Hydro One was interested in the energy and demand savings provided by the retrofit, whereas the client is interested in produce growth, particularly that of green peppers.
- The client has indicated that there are no major differences in the growth rate of the green peppers under the HPS or the plasma luminaires.
- When the plasma luminaires were cycled on and off, there were problems with the electronic drivers due to voltage fluctuations. The drivers were replaced and there have been no further problems with the plasma luminaires.