Are all LED luminaires created equal?

by Katie Daniel | April 15, 2015 10:39 am

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By Jeff Gatzow
Navigant Research recently released a report stating global unit shipments of light-emitting diode (LED) lamps and luminaires are expected to total 10.7 billion from 2014 through 2023. This statistic rings true in the Canadian market where most areas of the country are actively implementing LED streetlight programs or incentives. Additionally, the country is the third-largest user of lighting per capita behind Hong Kong and Norway.

While this is excellent news for reducing energy costs and consumption, how does the architectural and engineering community view this technology shift? Are LED luminaire manufacturers able to combine form and function to meet lumen requirements, esthetic specifications, and engineers’ and facility managers’ concerns? The answer is ‘yes,’ provided careful analysis and comparison is conducted on the various LED luminaires on the market.

LED luminaire form
Often, maximizing lumens per watt takes precedence with manufacturers over luminaires’ complementing architectural schemes. Additionally, meeting the needs of facility managers’ concerns about energy consumption also drives how products are designed and engineered. But, do these have to be mutually exclusive or can manufacturers achieve it all?

Lighting design necessitates an integrated approach—taking into account the exterior conditions, such as exposure to weather and pollution. Both in the dense urban spaces of the cities and in the surroundings of private buildings, the requirements are growing for precision lighting, energy efficiency, and visual comfort.

However, with quality and performance improving, and cost decreasing by about 18 per cent each year, LED technology is well-positioned for further adoption by the design community for general lighting.

Function and thermal management
Are all LED luminaires created equal? Manufacturers have different opinions on how luminaires should be engineered and designed to meet esthetics and function requirements, which involves the overarching issue of thermal management.

LEDs transmit heat, but they do not radiate it. This means while the fixture may be cool to the touch, it generates heat, similar to an incandescent fixture. This heat must exit the system through conduction and convection. Consequently, luminaire manufacturers must be conscious of potential heat dissipation challenges and how those challenges may affect LED performance, longevity, and even lamp safety. Inadequate thermal management will lead to a shift in colour, lower light output, and, in some cases, premature failure.

Time and market demand have a way of advancing technology to the point where thermal management may soon be just an afterthought rather than an obstacle in luminaire design. With each generation of LEDs, efficacy continues to rise exponentially; LEDs today are more than 50 per cent efficient—that is, they convert more energy into light than they do into heat.

However, thermal management involves more than just evacuating heat from the fixture; it includes using the best LED and being able to operate at a low drive-current while still providing high lumens per watt. A lower drive-current means less heat, which allows the fixture to manage heat better.

In evaluating manufacturers’ LED luminaires for both form and function, another important issue is the power supply. The type selected for a lighting application will be based on several factors. First, the environment where the application will be operating in must be considered. For example, is the application for indoor or outdoor use? Does the power supply need to be waterproof or have any special ingress protection (IP) rating? Will it be able to use conduction cooling or only convection cooling?

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According to the U.S. Department of Energy’s (DOE’s) Office of Energy Efficiency and Renewable Energy, the temperature at the junction of the diode determines performance, so heat sinking and air flow must be designed to maintain an acceptable range of operating temperature for both the LEDs and the electronic power supply. Luminaire manufacturers can be asked to provide operating temperature data at a verifiable temperature measurement point on the luminaire, and data explaining how temperature relates to expected light output and lumen maintenance for the specific LEDs used.

Regardless of how efficient LED fixtures are at dissipating heat, ambient operating temperatures still play a major role in a product’s lifecycle. Naturally, warmer climates make it harder to maintain the lowest possible operating temperatures during peak summer months. However, cooler geographical areas have lower temperatures, therefore ensuring a longer life for light-emitting diodes—the cooler the climate, the more ideal it is for LED luminaires.

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Retrofit considerations
Many LED retrofit lamps do not retain the exact form of their non-LED counterparts. This can lead to challenges with fit, function, and/or thermal management when installed in standard luminaires. Additionally, some LED retrofit lamps’ packaging indicates the lamps are not designed for use in enclosed luminaires such as recessed downlights. If LED retrofit lamps require access to ambient air for thermal management, installing the glass lenses often used with standard luminaires can damage or severely affect the lamp’s performance and life cycle.

Further, LED sources can appear extremely bright and/or pixilated and require appropriate shielding and/or cut-off for comfortable application. Unless a manufacturer has optimized the luminaire to account for a specific lamp, performance and appearance may be compromised when LED retrofit lamps are installed.

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Canadian utility rebates
Equally important is to determine whether end-users will be able to take advantage of utility rebates and other subsidies for products meeting a particular level of efficiency and power factor correction. Rebates for lighting upgrades are alive and well, with rebate organizations having updated programs for 2015.

Toronto Hydro’s BIP
Through the Business Incentive Program (BIP), Toronto Hydro-Electric System offers incentives to all owners and operators of commercial lighting and industrial lighting buildings in the City of Toronto. The incentives are $400/kW for lighting upgrades, and $800/kW for other energy saving upgrades. Projects are evaluated to ensure true kW reductions are achieved and retrofits remain in operation for three years.

BOMA Toronto’s CDM program
The Building Owners and Managers Association (BOMA) Toronto Conservation Demand Management (CDM) Program is available for commercial properties in the city that are more than 2322 m² (25,000 sf). The incentive for projects is either $400/kW on-peak demand reduction or $0.05/kWh of annual consumption reduction up to 40 per cent of the projects capital cost.

HydroOne’s ERIP
The Electricity Retrofit Incentive Program (ERIP) program is for commercial buildings outside of Toronto. ERIP is delivered through a local distribution company (LDC) however, not all LDC participate in the program. ERIP provides a range of incentives for prescriptive applications such as exit-sign upgrades, as well as offer an incentive of $0.05/kWh for custom projects.

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NRCan EcoEnergy
Natural Resources Canada’s (NRCan’s) Office of Energy Efficiency (OEE) offers the ecoEnergy Retrofit Incentive for Buildings. This program targets owners of small and medium-sized buildings in the commercial and institutional sectors that often lack the financial and technical resources to make energy improvements. New energy efficiency projects could receive up to $10 per GJ of estimated energy savings, or 25 per cent of eligible project costs, of $50,000 per project. When applying, an energy audit of the building is required.

Enbridge HPNC
The Enbridge High-performance New Construction (HPNC) program rewards builders and project decision-makers with incentives for offsetting the cost of energy-efficiency measures, achieving lower long-term operating costs, greatly improved marketability, and enhanced occupant comfort. By designing and building new buildings with more energy-efficient equipment for lighting, space cooling, and ventilation, buildings will cost less to operate, have lower environmental impacts, and be a comfortable place in which to live, work, or play.

Ontario IDF
The Innovation Demonstration Fund (IDF) is a discretionary, non-entitlement funding program administered by the Ontario Ministry of Economic Development and Innovation. The program focuses on emerging technologies, with a preference toward environmental, alternative energy, bio-products, hydrogen, and other globally significant technologies.

The purpose of the IDF is to support any pilot demonstrations that will then lead to the commercialization of processes and/or products in Ontario that are globally competitive and innovative sustainable technologies.

SEAD street lighting
Introduced last year, the Super-efficient Equipment and Appliance Deployment (SEAD) procurement program is first of its kind to support the purchase of energy-efficient LED street lighting in British Columbia. The program helps local governments and other public sector purchasers in the province reduce energy consumption and save on costs.

Nearly all of British Columbia’s 360,000 street lights currently use high-intensity discharge (HID) lamps. Though HIDs are far more efficient than older incandescent lighting options, switching all street lights to LED would save the public sector purchasers approximately 105 GWh of electricity annually, which is enough to power 10,000 homes. Also, the provincial greenhouse gas (GHG) emissions would be reduced by 14,000 tons. LED streetlamps also offer lower maintenance costs, a longer lifespan, reduced light pollution, and better visibility for pedestrians and motorists.

Conclusion
With the dramatic proliferation of LED luminaire in full force, this solid-state lighting (SSL) technology (i.e. LEDs) will dominate general illumination going forward. That being said, there are hurdles manufacturers and those specifying LED luminaires must overcome. Specifiers must conduct due diligence on products, particularly because since 2006 there have been 600 new lighting manufacturers in the LED industry.

Designers and specifiers need to play an active role in the development of standards and code requirements to ensure quality lighting is maintained. Beyond important lighting metrics such as efficacy, lumen output, and luminous distribution, designers and specifiers are needed to define the essential attributes of lighting as it becomes integrated with building automation, energy management, and security systems.

[6]Jeff Gatzow is national sales and marketing manager of lighting with Optec LED Lighting. He has worked in the LED luminaire industry for over 10 years, and prior to this he worked in the illuminated signage/brand identity industry. Gatzow can be reached by e-mail at jgatzow@optec.com.

Source URL: https://www.constructioncanada.net/are-all-led-luminaires-created-equal/

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