Photo courtesy TSDC
Improved lighting control technology
Dimming technology has evolved considerably over the last decade, especially in the arc discharge lamp category. What began as a device for simply matching lighting levels to various tasks and moods has emerged as a tool for decreasing energy use. The reduction in light output can be accomplished either as a step function or as a continuous one. (See Joe Knisley’s “Understanding Lamp Dimming,” in the February 2003 issue of Electrical Construction and Maintenance).
A ballast is an internal device built into a fixture intended to limit the amount of current in the electric circuit. Fluorescent lamps require a burst of power to move to full brightness, but less power once they are fully on. It is the job of the fixture’s ballast to regulate this variability in electrical current. In this application, the Toronto South Detention Centre (TSDC) installed a control system requiring the use of a digital addressable lighting interface (DALI) dimming ballast incorporated into each fixture.
DALI defines a new standard for digital communication between a lighting system’s individual components. It provides simplified communication and installation, yet maximum control and flexibility; wiring is simpler, installation fees are lower, and each ballast can be individually controlled. Additionally, maintenance costs are reduced through central monitoring of ballast and lamp status, and energy expenses are lowered through daylight harvesting and standard controls, such as occupancy sensors.
Lighting controls in action: TSDC
Construction of the new $330-million, 1650-bed detention centre ensures current and future capacity needs are met and resolves issues regarding overcrowding at the aging Toronto jail. The complex contains an integrated state-of-the-art security system and all essential functional components, including:
- admissions and release;
- health services;
- education;
- life skills;
- counselling;
- recreational programs;
- visitation;
- materials management; and
- support such as laundry, food services, and maintenance.
On behalf of the Ministry of Community Safety and Correctional Services (MCSCS), Infrastructure Ontario built a new maximum security detention centre on the site of the old Mimico Correctional Facility. Toronto South Detention Centre consists of four main towers to house inmates along with a large administration building and a new Toronto Intermittent Centre that replaces the function of the previous Mimico facility.
This new building is part of MCSCS’ strategy to address health and safety issues and inefficiencies of design, technology, and space by replacing older facilities that do not meet current operational requirements and are experiencing significant and growing remand pressures.
TSDC’s design and construction adheres to the guidelines and sustainability principles of Canada’s Green Building Council’s (CaGBC’s) LEED rating system. Under the aforementioned FBI, all new federal office buildings are required to meet LEED Gold, and renovations of existing office buildings must meet Silver. By focusing on a healthy indoor environment, reduced greenhouse gas (GHG) emissions, and efficient use of energy, water, and other resources, the facility achieved the requisite Silver level. The first green-certified detention centre in the province, TSDC’s sustainable design includes:
- ground source heat pumps, which provide 2.2 kWh (7.8 MJ) of energy and reduce the building’s natural gas consumption by a minimum of 40 per cent;
- low-flow technologies, which decrease water consumption by 20 per cent;
- diversion of 75 per cent of construction waste from landfills; and
- adhesives, paints, carpets, and sealants that emit only low levels of volatile organic compounds (VOCs).
The facility’s form begins with a two-storey front building that provides the core elements, and rises to two seven-level housing towers. The entry structure relates to the street and its pedestrian scale. The design was reviewed and approved by the City of Toronto for compliance with urban design principles going beyond the requirements of zoning and planning ordinance.
To reach high-performance lighting goals and meet LEED requirements within budget, Crossey Engineering, in collaboration with Ozz Electric, selected fluorescent luminaires using 347-V DALI dimming ballasts. More than 2500 maximum security fixtures were installed––of these, approximately 900 were specifically for the cells. Energy-efficient T5HO lamp sources were customized by adding DALI dimming ballasts––for use with controls––to further optimize the fixtures’ efficiency. This has enabled the facility to realize attractive cost and energy savings on an ongoing basis, offsetting the initial price of its lighting investment.
The building design team’s intention was to save as much energy as possible in the seven-storey, 20,439-m2 (220,000-sf) prison building, while creating the correct lighting environment with the appropriate lighting fixtures to provide maximum efficiency.
Conclusion
From a sustainability standpoint, correctional facilities are 24-hour, energy-intensive structures that focus on security. The benefit of greening correctional facilities is they will consume fewer resources, create less pollution, and provide healthier environments for the users––inmates, staff, visitors, and administrators. (See Mindy Feldbaum, Frank Greene, and Sherry Carroll’s “Greening of Corrections: Creating a Sustainable System.”)
While the primary goal of correctional buildings is safety for the community and for those housed and working within the facilities, increasingly, sustainability goals and strategies are being integrated into the policy and planning initiatives of the corrections community. Lighting controls coupled with state-of-the-art luminaires provide an excellent solution to reducing energy consumption and costs.
Frank Gonzalez is the regional sales manager with Kenall in Gurnee, Ill., a producer and supporter of durable lighting solutions for demanding environments such as correctional facilities. Gonzalez has worked in the lighting manufacturing business for 27 years and is a longtime member of the Illuminating Engineering Society of North America (IESNA). He can be reached via e-mail at fgonzales@kenall.com.
