As the idiom suggests, the difference between night and day is dramatic — particularly when viewed from a literal illumination standpoint. High noon on a sunny day will introduce 8,000 foot-candles of light to the earth. By comparison, a moonlit night — one bright enough to read a newspaper by — produces three one-hundredths of one foot-candle. Thus, turning night into something resembling day for sports participants, fans and live television audiences is not a task to be taken lightly.
How sports lighting manufacturers go about it varies, but the arc of the industry appears as predictable as the earth's daily rotation around the sun. According to some industry experts, rapidly advancing LED technology will render obsolete the high-intensity-discharge (HID) metal halide lamp — the sports lighting staple that hasn't changed significantly in decades — perhaps within the next several years. Few deny LED technology's bright future based on its reliability, versatility and energy efficiency, but its comparatively high capital investment costs have thus far kept it in the outdoor market's shadows.
"In 2014, LED equipment in an average application might cost 50 percent more than HID," says Musco Lighting CEO Joe Crookham, whose company's metal halide lighting solutions currently illuminate seven Major League Baseball parks and countless outdoor sports venues worldwide. "My guess is that somewhere in the three-to-five-year range, LED equipment will get to the place where it does not cost a premium over HID, in which case there will be no reason to buy HID. If you can buy LED for the same or less and gain all the benefits of the LED, it will replace HID completely. We're crossing a watershed point."
Obsolescence is likely to come even quicker for HID metal halide lamps in the indoor arena, where Musco and others already boast LED installations. One reason: The energy efficiency of LEDs is magnified in buildings that are used perhaps 4,000 hours out of the year versus the 400 hours of use a stadium might see. Stadium operators may be reluctant to make the capital investment if the ROI isn't realized short term. "On a high school football field that runs 50 or 70 hours a year, we don't get a lot of discussion from people about the energy savings, because they just don't use enough energy," Crookham says. "But the superintendent in the high school system cares about what it costs to run the lights in the gymnasium."
On the manufacturer's side, there are plenty of factors to consider when taking LED technology outdoors, not least among them weather — high winds, rain, freezing temperatures — and distance. A fixture in the arena setting might be required to throw light 125 feet to the playing surface, whereas an outdoor stadium might dictate throw distances five times as long. "You need to light up second base on a baseball field," says Joe Casper, chief technology officer at Ephesus Lighting Inc., which is currently in negotiations with three NFL teams to convert their stadium lighting to LED. "On the backside of some of these NFL stadiums, you're up about 200 feet, and now you're throwing light down 600, 700 feet to hit the 50-yard line."
While a metal halide fixture relies on sophisticated reflectors to focus and project light emitting from the bulb's four-inch-long arc tube, an Ephesus LED fixture concentrates light from a proprietary number of comparatively tiny LEDs clustered behind 144 point sources arranged in quadrants across a 20-inch diameter lens. Years in development, the lens consists of polycarbonate materials specially designed to focus the light, as well as a hydrophobic component that repels water and dirt. No reflectors are required. "We're producing nearly three times as much light as we do with our indoor fixture," Casper says. "We then need to take the light we have generated and focus it very precisely."
So precise is the light cutoff in LED fixtures that visors employed by traditional stadium lighting to guard neighborhoods below and the dark skies above from light pollution aren't needed, either (though the Ephesus fixture design includes a visor solely because end users expect to see one). "It's almost razor-sharp definition of light to the playing field," Casper says. "We light the playing field and keep it dark in the seats."
Adds Crookham, comparing the BB-sized point source of one LED favorably to that of a metal halide lamp, "It allows you to be more efficient, because you spill less, waste less, and you don't have to bounce light two or three different times in a fixture to be able to get control of it like you do if you have a long arc tube."
The Ephesus LED fixture, which garnered UL safety and performance certification earlier his year, is designed to retrofit fixture-for-fixture into any stadium's existing lighting scheme, though far fewer LED fixtures are needed.
One stadium currently pondering conversion employs 753 1,500-watt metal halide fixtures that consume roughly 1,600 watts each and put about 175 foot-candles of light on the field. Casper says his product can match that light performance level with 192 LED fixtures consuming 1,000 watts each, saving more than a million watts. "However, they're not meeting NFL standards," Casper says of team officials. "They want to be at 250. So we're going to pump them up to 250 foot-candles with only 292 light fixtures, and we're still coming in there almost exactly at a 75 percent energy reduction."
Maintenance, or lack of it, is another source of savings. Ephesus fixtures are designed to function for 225,000 hours before experiencing lumen depreciation of 30 percent (roughly half a percent per year), but each fixture is built with enough lumen "headroom," as Casper calls it, to compensate for that depreciation. "We know how to dial that in so there is no lumen decay," he says, noting that individual fixtures not only receive control information wirelessly, but transmit performance data, as well. (All control capabilities witnessed in Ephesus Lighting's indoor LED installations — instant-on functionality and visual entertainment programming — will carry over to the stadium setting, where even the 144 point sources of light within individual Ephesus fixtures will be programmable. "You can have a fireworks show without fireworks," Casper says.)
Potential savings turn exponential when applied to Major League Baseball parks hosting 81 regular season games, the vast majority of them at night. The upfront investment in conversion is significant — somewhere in the range of $700,000 to $900,000 for hardware alone — but utility incentives could drive that price down by $100,000 to $250,000. Depending on geographic location, a stadium could also see a reduction in utility demand charges (a fee assessed for merely powering up a stadium's lighting system and thus taxing the grid during times of peak summertime energy consumption) of anywhere from $100,000 to $125,000.
Crookham contends that things like demand charges don't amount to much of a line-item concern in the budgets of organizations spending millions on individual player contracts. "On the other hand, if they can promote the fact that they've gone to LED and are now a good citizen and all that sort of thing, that's where it starts to matter to those people," he says. "It's going to be more about show."
For a handful of professional teams, showtime is coming sooner than later. Casper expects the first Ephesus outdoor installation to take place before the end of July, and he's predicting that once the first organization takes the leap of faith that LED technology can handle both the elements and the team's illumination needs, others will follow. By next year, half a dozen pro franchises could be making the switch.
"It's going to happen. It has to happen," Casper says. "It's going to be the way of the future."
Building a Better Blast
Within the past 35 years, manufacturers have succeeded in improving the efficiency of metal halide lamps — still the dominant player in the outdoor sports lighting marketplace — primarily by mitigating the amount of light wasted by each fixture. Precisely engineered reflectors capture the light emitted from the lamp's four-inch arch tube and direct (and redirect) it toward the field of play — the greater the distance the light has to travel, the more focused the light leaving the fixture must be.
A more recent development in metal halide technology is the introduction of the electronic ballast, which "hit the streets hard a little over a year ago" and offers more efficiency and user control over the traditional magnetic ballast, according to Bill Smith, vice president of sales and marketing for Qualite Sports Lighting LLC. Operating at a higher frequency, the electronic ballast can boost a fixture's light output to 115 lumens per watt, or roughly 30 more lumens per watt than a magnetic ballasted fixture. "An electronic ballasted system produces more lumens per watt, which means more light," says Smith, whose company manufactures the GreenStar™ electronic ballast lighting system. "Obviously, more light, you're reducing fixtures. When you're reducing fixtures, you're reducing energy."
Not only do electronic ballasts require up to 40 percent fewer fixtures to light an outdoor field and fewer input watts (1,565 compared to a magnetic ballast's 1,625) to get 1,500 watts of output per fixture, they also are much easier on the lamps themselves. "When you turn on your fixtures in a magnetic ballast system, it creates an over-voltage situation," Smith says. "It's slamming those lamps with power to get them to ignite. That's the most degradative thing on a lamp. An electronic ballast can monitor the exact amount of voltage needed to ignite, so it's much healthier on those lamps."
Ignite time is reduced to 10 minutes (compared to 15 or 20 in a magnetic ballast system) and, once the lights are on, electronic ballasts offer the added benefits of wireless control, remote diagnostics and the elimination of the humming noise made by magnetic ballasts, as well as dimming capability down to 50 percent on each individual fixture. — P.S.
As the professional tennis circuit has popularized blue and purple courts, the color that matters most to municipalities and private clubs alike in terms of lighting their facilities is green — as in environmentally responsible and economically smart.
Given its tight dimensions compared to most outdoor (and even indoor) sports, tennis presents a number of lighting options, from fluorescent tubes to HID metal halide bulbs.
ThinkLite, a five-year-old company that has found a niche lighting outdoor tennis courts, is serving up greener solutions in the form of LED tubes and induction bulbs while still delivering to courts the requisite 35 to 50 foot-candles for nighttime play.
"Instead of bringing in a brand new fixture or some other type of pole, it's really as simple as taking out these existing fluorescent tube lights, retrofitting the exact same fixtures and the exact same infrastructure with our LED tube lights and — boom — you have light levels that are comparable if not significantly better than the existing light," says ThinkLite CFO and COO Danny Wadhwani. "So that ease of going to something that is 50 to 60 percent more energy efficient without having to spend an arm and a leg on installation is really a valuable proposition and it's definitely getting a lot of interest."
The only wrinkle to the conversion process involves disconnecting existing ballasts, which are no longer needed.
Conversion is costly — compare the $50 price of 16-watt LED tubes to 32-watt fluorescent tubes that can be purchased at Home Depot for less than $3 — but the benefits are clear. There's the energy efficiency (131 lumens per watt compared to 90), but also maintenance savings (ThinkLite's LED tubes boast a rated lifespan of 50,000 hours). "When a lamp or a ballast goes out, it's not just buying a new lamp or ballast. Many times it's getting a lift out there, getting an electrician out there to fix it," Wadhwani says. "It's very expensive."
For metal halide conversions, ThinkLite offers induction bulb technology that delivers 100,000 hours of 165-lumens-per-watt performance. Moreover, the induction bulb's glare-free characteristic makes it well-suited to the tight quarters of a tennis court.
"There are options out there for anyone looking to be greener," Wadhwani says. "They're tried, they're tested, they're proven." — P.S.
Level Playing Fields
According to Musco Lighting CEO Joe Crookham, quality of light is as important as quantity, and by quality he means consistency of light level across the playing field. "Whatever the brightest light is, that's what the eye will adapt to, and everything else below that will look relatively darker," he says. "You could actually have better visibility if you took the brightness off the bright spots and had the average light lower."
Often, what facility managers think they have in terms of light levels and what they're actually getting is vastly different, and they should seek performance guarantees from their field lighting supplier. Here are target foot-candle levels that Crookham says are common for various levels of football and baseball:
HIGH SCHOOL FOOTBALL
MAJOR LEAGUE BASEBALL
300 foot-candles (infield)
225 foot-candles (outfield)
LITTLE LEAGUE BASEBALL
50 foot-candles (infield)
30 foot-candles (outfield)