Cast Study - Seattle's Amy Yee Tennis Center
This project consisted of replacing the Seattle Parks Dept. Amy Yee Tennis center lighting on their ten indoor tennis courts. The existing lighting was comprised of 12.8 1,000-watt metal halide fixtures per court, for a total of 128 for the entire facility. The metal halides were suspended at 16’ aimed at the 40’ ceiling, producing an indirect light source. At the end of each court, 10’ behind the baseline, were four 8’ 2-lamp 460-watt T12 VHO fixtures suspended at 16’, aimed directly down to the court. Courtlite worked closely with Seattle City Light and the Seattle Lighting Design Lab to develop a solution that would radically reduce the facility’s energy consumption, dramatically increase the light quality, and provide manageability. The solution was the Courtlite Pro Direct Lighting System integrated with an Alerton lighting management control system custom designed for the Courtlite System by ATS Automation.
Pacific Energy Solutions approached this project with several objectives: energy reduction, increased light quality, system manageability, and substantial project funding from Seattle City Light. The Seattle City Parks Dept decided to install the Courtlite Pro lighting system, consisting of twenty-four 8’ six lamp T5 fixtures (12 twelve fixtures per side). The Courtlite fixtures were suspended 20’ above the floor and 6’ feet beyond the sidelines. The proprietary design of the fixture allows the light source to be aimed at 45 degrees to the court for uniformity. The existing lighting system was operating at full capacity 16 hours per day since the 1,000-watt metal halides take too much time to warm up. Due to the instant ON/OFF feature, the Courtlite Pro fixtures are designed for several lighting levels: totally off or only 2-lamps (2,808-watts) per fixture are on when the court is vacant; 4-lamps (5,616-watts) per fixture for recreational play; and all 6-lamps (8420 watts) for tournament play. Matched with the Alerton management system, the lights on the individual courts are automatically turned on for the time that the court is booked, and then go to vacancy mode. The final results of this project include a reduction of 750,000 Kwh per year (73%) with an annual savings exceeding $40,000. Equally as important, there’s a dramatic increase in light quality.
| Fixture description | Existing fluorescent | Existing 1000-w HID | New Courtlite T-5 w/ management |
| Quantity of fixtures | 80 | 128 | 240 |
| Lamps per fixture | 2 | 1 | 4 |
| Lamp type | T-12 fluorescent 215-W VHO | 1000-W MH | 54-W T-5 HO |
| Watts per fixture | 462 | 1080 | 234 |
| Total watts per court | 3,696 | 17,520 | 5616 |
| Total watts all courts | 36,960 | 175,200 | 56,160 |
| Operating hours per day | 16 | 16 | 11.9 |
| Operating days per week | 7 | 7 | 7 |
| Operating weeks per year | 52 | 52 | 52 |
| kWh per year | 212,866 | 795,444 | 240,240 |
| Total kWh per year existing | – | 1,008,310 | 240,240 |
| Cost per kWh | $0.0586 | $0.0586 | $0.0586 |
| Energy cost per year | $12,474 | $46,660 | $14,078 |
| Total annual energy cost | – | $59,134 | $14,078 |
| Total savings per year | – | – | $45,056 |
| Savings percentage | – | – | 73% |
| Total kWh saved | – | – | 768,070 |
