Focus on Lighting: Taking Control of Architectural Lighting
Architectural lighting should be designed to complement your needs and as your needs change throughout the day, your lighting should adapt accordingly. Lighting controls are the answer. Several options are available to help make your environment and your life more comfortable and “green”.
Lighting controls can be as simple as the familiar toggle or rocker switch at the entry into a room or a sophisticated building-wide system that monitors occupancy, time of day usage, special events, and even events based on the sun’s cycle throughout the year. In the past, lighting control systems were often seen as a luxury, used to help set a mood; now they are a critical part of the overall lighting system (both simple and complex) still helping to set the mood and environment and also a necessary part of a complete energy-saving system.
In designing the lighting control system, first considerations should be the space and task function (how will the space be used) followed by budget, any special considerations related to local codes, day-lighting requirements, control flexibility, and systems integration. The cost of a lighting control system is frequently offset by savings in energy usage through effective monitoring of need relative to daylight, usage and time of day operations.
Historically, wall switches are line voltage devices, which open and close the phase wire (hot wire) that supplies power to the light fixture. Located at entry to a space or at locations convenient to the user, these offer an easy and the most cost effective way for fixtures to be turned on and off.
Wall box dimmers are slightly more expensive but provide flexible control of light output down to the minimum level provided by the dimming hardware while reducing the overall load consumption. Standard wall box dimming allows most filament lamps to be dimmed smoothly from full brightness down to zero light output. Other light sources require additional hardware for effective dimming: fluorescent sources require the use of fluorescent dimming ballasts which receive a signal from a control device and control the lamps accordingly; solid state (LED) sources demand the use of drivers with dimming capabilities.
For spaces where different moods are required, the end user may consider the incorporation of a controller that permits different combinations of lighting zone switch and dimmer settings to be recalled. For instance, in a corporate conference room you may want all of the lights at full brightness during a staff meeting and the lights near the projection screen or flat panel dimmed during a presentation. A scene controller allows this transition to be made with the push of a button.
When looking at an entire building, whole building controls can fully integrate lighting, shading, and sensors for maximum energy savings. These solutions can be easily designed, installed and reconfigured to meet the changing needs of a building. Control systems can incorporate an integral time clock feature to enable scheduling of lights and shades by time-of-day (e.g., 8:00 pm weeknights) and astronomic time clocks (e.g., dusk or dawn). Various manufacturers have developed systems that allow facility managers to conveniently manage both electric light and daylight right from their desktop. They can control, configure, monitor, and report on the lighting for any space in the building for maximum energy efficiency, comfort, and productivity.
The benefit of implementing any lighting control system is reduced heating and cooling costs as well as increased comfort and safety of the users.