High-Efficiency Lighting Systems and Networked Lighting Controls (NLCs)

What are High-Efficiency Lighting Systems and NLCs?

A high-efficiency lighting system integrates daylighting and energy efficient electrical lighting with networked lighting controls (NLCs), to provide a comfortable environment for occupants while reducing energy consumption and costs (see Daylighting, and Smart Sensors and Controls).[1] Lighting accounts for about 5% of the annual energy costs in a typical household and contributes to a household’s cooling load by emitting waste heat.[2] More stringent building codes, a phasing out of traditional lighting technologies (e.g., incandescents), utility incentives and rebates, and more energy efficient federal standards for lighting applications (e.g., screw-in light bulbs) have helped to drive the market for energy-efficient lighting in the residential sector.[3]

Fig 1 shows the evolution in energy use, cost savings, and lifespan of light bulbs  from standard incandescent to more energy efficient options. The least efficient replacement option is halogen incandescent which are 30% more efficient, followed by compact fluorescent light bulbs (CFLs) which are 75% more efficient, topped by light emitting diodes (LEDs) which are 90% more efficient than traditional incandescent light bulbs.[4]

Currently available smart bulbs equipped with smart sensors and paired with networked lighting controls that allow for lighting customization and control such as scheduling, daylight harvesting, vacancy sensing, and control of light color and brightness, promise to offer additional performance and efficiency gains and an enhanced occupant experience (see Smart Sensors and Controls).[5] By providing a foundation for future applications of the IoT (Internet of Things), high-efficiency lighting and networked lighting controls hold the potential to create new benefits and functions beyond supplying basic illumination, such as enhanced security, indoor environmental quality monitoring, and remote maintenance and service through.[6]

How to Implement a High-Efficiency Lighting System and NLCs

High-efficiency lighting design involves complex interactions among multiple building systems and disciplines, requiring an integrated design process (see Integrated Design Process). For example, window selection and placement influences daylighting and electrical lighting design, sizing of mechanical systems, and interior design layouts (see Energy-Efficient Windows, Glare and Heat Gain Reduction, and Properly-Sized HVAC Equipment).

Lighting guidelines provide general principles and examples, but project specific solutions often require hiring a lighting expert familiar with advanced computer simulation software and tools that can simulate a range of scenarios and outcomes.[7]

The following provides general best practice guidance on how to optimize daylighting and electrical lighting in new residential buildings.[8]Set a Maximum Lighting Power Density (LPD) goal to avoid overlit spaces and to achieve an appropriate level of lighting per area lit or watts per square foot.

1. Set a Daylight Sufficiency Goal that establishes the amount of daylighting, measured in lumens or foot-candles, required to perform a typical task in each space without electrical lighting.
2. Develop a layered lighting strategy that first utilizes daylight to provide primary or ambient lighting levels, and then adds electrical lighting options and controls to vary lighting levels for a variety of tasks and occupant preferences.
3. Specify ENERGY STAR qualified lighting products that are at least 75% more efficient and last 25% longer than incandescent lighting.[9]
4. Use the Federal Trade Commission’s “Lighting Facts Label” to determine a light’s brightness, measured in lumens, annual energy cost, lifespan, and light appearance, measured from warm to cool.[10]  
5. Use vacancy sensors (manual on, automatic off) as opposed to occupancy sensors (automatic on, automatic off) to save energy by requiring occupants to flip a switch if they require additional light.
6. Provide adjustable task lighting such as under cabinet lighting to save energy by reducing ambient lighting needs and directing appropriate lighting to specific tasks.
7. Incorporate exterior motion sensors to save energy and enhance security and safety.
8. Consider installing solar powered outdoor LED lights for lighting outdoor pathways.
9. Plan for backup power for critical lighting needs during a power outage, such as emergency and night-time lighting (see Energy Storage and Backup Power Generation).

Examples

Residential lighting upgrade, Southbury, CT.

There were 124 individual lights changed in the home, delivering a savings of over $200 per month amounting to $2,533 per year.  The total investment was  $6,024 and the payback period is 2.4 years. The savings are based on the total delivered power cost of $0.16/kw‐hr.

Outdoor entry lighting on a residential home, Albany, NY.

• The ceiling-mounted incandescent luminaire in front door entry replaced with motion sensor and Energy Star-rated CFL luminaires
• Reduced glare
• Lit the entry at dusk, improving safety without leaving lights on all day
• Reduced energy use
• Estimated annual energy savings of 208 kW l and an energy bill savings of $30

Benefits

Supplementing natural daylight with high-efficiency lighting systems and NLCs provides multiple benefits:

• Reduced utility bills through energy efficiency gains and reduced maintenance and replacement cost through longer-lasting bulbs and fixtures.[11]
• Reduced cooling loads and downsized HVAC systems through less heat gain from electrical lighting (see Properly-Sized HVAC Equipment).[12]
• Reduced number of toxic chemicals released into the waste stream and reduced light pollution.
• Improved occupant satisfaction based on a shared preference for naturally daylit spaces, reinforcement of circadian rhythms, and connection to nature.[13]
• Increased resale value of the home (1%-3%).[14]

Costs

EnergyStar certified LED light bulbs in common replacement sizes for traditional lighting (40 and 60W) cost around $2 per bulb and pay for themselves in energy saved in a few months.[15] Utility incentive programs and product manufacturer rebate programs can also help offset upfront costs. See the NJ Clean Energy Office for available incentives.

Resiliency

Implementing high-efficiency lighting and NCLs provides energy savings and reduces reliance and stress on the electricity grid. Daylit-optimized homes paired with high-efficiency lighting systems and built-in backup power for critical lighting needs further reduce stress on the grid, especially in the event of a power outage.

[1] Whole Building Design Guide. (WBDG). Energy Efficient Lighting. http://www.wbdg.org/resources/efficientlighting.php (accessed May 16, 2018).

[2] US DOE. 2018. LEDs. https://www.energy.gov/energysaver/save-electricity-and-fuel/lighting-choices-save-you-money/led-lighting (accessed Dec 19, 2018).

[3] The Energy Independence and Security Act (EISA) requires general service lighting products sold as of January 1, 2020, to have an efficacy of at least 45 lumens per watt.

[4] EnergyStar. 2017. “The Light Bulb Revolution: EPA Predicts Widespread Adoption of LED Lighting by 2020 if Utility Programs Persist.” https://www.energystar.gov/sites/default/files/asset/document/LBR_2017-LED-Takeover.pdf (accessed Dec 19, 2018).

[5] US DOE. 2017. “Guiding SSL Technology Advances.” Department of Solid-State Lighting. https://www.energy.gov/sites/prod/files/2016/09/f33/guiding-ssl-technology-advances_sep2016.pdf (accessed Dec 13, 2018).

[6] Iain Campbell et al. 2017. “A New Way to Think About Office Lighting.” Harvard Business Review. Rocky Mountain Institute (RMI) Buildings Program. https://hbr.org/2017/06/a-new-way-to-think-about-office-lighting (accessed Dec 13, 2018).

[7] WBDG. Daylighting. http://www.wbdg.org/resources/daylighting.php (accessed April 4, 2018).

[8] General Service Administration (GSA) Office of Federal High-Performance Green Buildings. 2018. “Saving Energy Through Lighting and Daylighting Strategies.” https://www.gsa.gov/cdnstatic/Lighting_and_Daylighting_Two_Pager_508_compliant_2-9-15.pdf  (accessed Dec 11, 2018).

[9] US DOE. 2018. LEDs. https://www.energy.gov/energysaver/save-electricity-and-fuel/lighting-choices-save-you-money/led-lighting (accessed Dec 19, 2018).

[10] Federal Trade Commission. 2017. “The FTC “Lighting Facts” Label: Questions and Answers for Manufacturers.” https://www.ftc.gov/tips-advice/business-center/guidance/ftc-lighting-facts-label-questions-answers-manufacturers  (accessed Dec 19, 2018).

[11] Ibid WBDG.

[12] Efficient Windows Collaborative. 2018. Daylight Controls. Windows for High-Performance Buildings. http://www.commercialwindows.org/daycontrols.php (accessed July 5, 2018).

[13] California Energy Commission and Heschong Mahone Group. 2013 “Office Daylighting Potential” http://www.sunlightindoors.com/resources/SunlightBenefits/OfficeDaylightPotential.pdf (accessed April 5, 2018).

[14] Consumer Reports. “8 Ways to Boost Your Home Value” https://www.consumerreports.org/home-improvement/8-ways-to-boost-your-home-value/ (accessed May 17, 2018).

[15] EnergyStar. 2017. “The Light Bulb Revolution: EPA Predicts Widespread Adoption of LED Lighting by 2020 if Utility Programs Persist.” https://www.energystar.gov/sites/default/files/asset/document/LBR_2017-LED-Takeover.pdf (accessed Dec 19, 2018).