A lighting upgrade at the Royal Centre Pavillion in Vancouver, British Columbia achieved large electrical energy savings and significantly improved lighting levels and quality. The Pavillion was constructed in 1971 with the originally designed lighting still in place. The ceiling of the Pavillion comprised of 5 foot square cells 23 feet above the floor.

Each cell included a 400 watt, recessed mercury vapour downlight and four 4' long F40T12 striplights, mounted in a recessed slot around the downlight. The downlight was mounted in the centre if each cell at the top of the pyramid shaped coffered ceiling. The downlight design including a matte silver finish reflector and a dropped 6" matte black baffle. Ballasts were remotely located in the ceiling plenum and were not readily accessible. Due to the high maintenance and operating costs, Prism Engineering Ltd was requested to review the facility and provide recommendations to improve the system.

Upon our site investigation, a number of concerns were identified:

• Lighting levels slightly lower than desired;
• Lamp replacement costs considered too high;
• Ballasts replacement costs considered high due to access limitations;
• High electrical energy operating costs;
• Difficult lamp replacement access from below, due to stair opening. (many locations had been maintained through climbing through the ceiling space).

Prism Engineering presented a number of options for consideration. After careful consideration the following was selected for implementation.

• Replace the existing 400 watt mercury vapour downlight and baffle with new 100 watt pulse start, ceramic arc tube, protected lamp in a new downlight with specular clear reflector designed specifically for this lamp.
• Remove the fluorescent strip lights as located in each of the coffered cells.

The "protected" metal halide lamps were chosen instead of standard lamps. The use of standard metal halide lamps requires that fixtures include a protection shield to contain the lamp, should it break. The use of "protected" lamps eliminates this requirement. As such, building of scaffolding is not required to reach and replace the lamps. This significantly reduces re-lamping costs as lamps can be changed with the use of a lamp-changing pole from the floor below.

The most visible change to this very airy space is the lack of artificiality that the new lighting system imparts. This is most noticeable at the beginning and end of the day, as well as on the many overcast days seen during the winter months. The greenish cast that the old Mercury Vapour & Cool White lighting emitted has been replaced with a much whiter light with much better red components and more natural flesh tones. This critical improvement in CRI (Colour Rendering Index) from the low 50s to high 80s is impressive, yet at the same time seems completely natural and fitting for the relationship building and public interplay that occurs here. The comfort benefit of reduced lamp and ballast heat loading into the space should not be overlooked, either. Over time, the improvements in lumen depreciation and lack of colour shifting will only reinforce this choice of modern day technology.

The retrofit provides energy savings of 581,629 kWh annually or 63.5% of existing consumption, and savings from reduced maintenance. Simple payback for the project is calculated at 5.2 years.

	Before	After
Luminaire Types	Lobby lighting consisted of 400W mercury vapour luminaires and T12 fluorescent luminaires in cove.	Lobby lighting consists of 100W pulse start metal halide protected lamps in new luminaires. Existing fluorescent lighting in ceiling was removed.
Quantity	184 Mercury vapour downlights 736 F40T12ES striplights on magnetic ballasts	184 Metal Halide luminaires
Total kW	156.0	54.5
Annual Hours	5,408	5,408
Total kWh	915,716	334,087
Illuminance	25 to 35 fc	50 to 60 fc