LIGHTING SYSTEMS, CONTROLS & FUNCTIONALITY
Lighting today fulfills many objectives:
- Security
- Safety
- Functionality (tasks)
- Advertising (product enhancement)
With the advent and proliferation of low energy light options (LED) has confused many installers, designers and engineers fundamentally because they do not understand the mechanics of the light production and distribution.
LIGHTING SOURCES in the past produced light from a single point source (360o light bulb) and linear sources (360o fluorescent and neon). These light sources were easily controlled, tempered and directed without much light loss. The mechanics of the distribution was developed over a long period of time. What was difficult with standard lighting systems was lighting level control and lamp restart times. Glare was not a big problem with traditional lighting sources as mechanics could control it and maintenance and repairs were straight forward and routine.
LED sources are a whole new frontier. LED products can produce a lot of glare because of their concentrated point source array. These LED point sources project light only in a 180o spectrum compared to conventional lighting which projects light in a 360o spectrum. For the same amount of lumens (light output) the LED source will be twice as bright to look at. LED sources are typically whiter in colour making environments less comfortable; LED sources can also have a stroboscopic effect.
I was involved in a country club utility driven energy program targeting lighting. Our design incorporated considerable control, layout rework and design specific products. In the end they opted to go with a salesman’s pitch and just did product replacements from fluorescent and HID to LED without looking at product appropriation. In the end the indoor tennis courts were not playable due to the extreme level of glare, for three years management fooled around trying to reduce or eliminate glare. In this situation any attempt at reducing glare also reduced light levels at the same tennis courts. In the end the inappropriate fixtures were replaced with design specific costing the members three times the original cost plus three years of an ugly environment.
LED products are not as easily repaired in the field. There are no specifics to LED arrays and drivers not even to manufacturers. Most assemblies in time will need to be replaced and the product will no longer be in production and won’t be repairable, only replaceable.
Although LED equivalents to conventional lighting products use less energy, it is easy and common place to be careless with quantities and scheduling with the belief they don’t use much energy. This case was proved in the country club retrofit we mentioned earlier.
Where there was no redesign, no control or scheduling strategy, this resulted in minimal returns on costs due to continued high rates of consumption. The same thing happens with low fat, low sugar, low calorie foods where we tend to eat more because of the belief they are healthier. Irrelevant lighting, over lighting and daytime lighting is a large contributor to energy burden and light pollution. Bulk lighting switching can contribute to energy demand penalties. 1,000 watts of lighting running continuously 24/7 for 30 days will cost around $100, so it is easy to run up energy costs and energy waste with just one lighting circuit.
A commercial / retail asset where we acted in the capacity of functional and compliance consultant, we noticed much lighting throughout the property on all day. Our research found the controllers and pilot devices not functioning as intended. This was partly due to the complexity of the controllers and available lack of expertise to manage the programs. The majority of the lighting was poorly laid out or lack of integration to a pilot device or controller. Much of the lighting borders or parallels daylighting and some are outdoors in daylight. Even though these are all LED in the reverse much of the lighting in the off hours during the night or day also is not controlled effectively with effective set points to correlate with functioning hours and night or day, even over shooting set points can seriously affect the bottom line. If this property mismanages lighting to 150-200 kW/hour would have a significant environmental impact from light pollution and carbon footprint from wasted energy with an additional economic burden of $600/day.
The design morale is to use appropriate products only when and where required with controls and set points to define the operational needs and demands specifically.
Artificial lighting is one of the biggest consumers globally of energy. Much of the lighting is poorly designed and implemented so that much of it is not productive and actually has negative consequences.
Light pollution or artificial light at night, is the excessive or poor use of artificial outdoor light. It disrupts the natural patterns of wildlife and plants and contributes to the increase in carbon dioxide in the atmosphere, disrupts humans’ sleep and obscures the stars in the night sky.
Light pollution arises from careless and often misguided exterior night lighting practices. Light pollution wastes energy, causes hazardous glare, increases the production of greenhouse gases and compromises public safety. An unfortunate side effect of growth and development is increased levels of light pollution – light that doesn’t serve its intended purpose of providing safety and convenience. Instead it spills outward and upward from poorly designed or inefficient light fixtures trespassing on surrounding properties and polluting the skies. Over one billion dollars a year is wasted in North America alone because of ineffective or inefficient lighting.
