Rosetta Stone

October 27, 2021

Electric Lighting + Energy Savings

Talking Points • Research Brief • Collection Database

Summary

In commercial applications, lighting can account for up to a third of a building’s total energy load. Fortunately, lighting technology is evolving so rapidly that it has become a huge opportunity for significant energy savings. Case study research has demonstrated that with the introduction of networked lighting controls, newer lighting systems are able to significantly reduce electricity consumption and demand up to 70%. For new construction projects, it’s critical that new lighting technology be considered, not just for reducing the overall EUI of a building, but for future-proofing the building – allowing the project to keep up with technological advances within the lighting industry.

Overview

I. Controls-Based Lighting Systems

Since lighting represents a significant portion of energy consumed in commercial office buildings, it is imperative to consider the use and effectiveness of advanced lighting controls to reduce energy consumption. In this paper from Parise et. al. they analyze the energy performance of an interior lighting system and propose a tool to help accurately quantify the savings. The proposed tool can be used to optimize the design of the system according to the proper characteristics of a room and how that space might be used. The tool can also be used as an energy management system to verify and monitor the lighting system’s performance over time. Overall, the paper highlighted – through a simple case study – the importance of an appropriate control in order to increase the actual energy performance of the system. Having a control system is a great step, but to boost savings one must select the most appropriate system for the space, which is not always the most expensive option. 

Interested in the potential of lighting control systems, Myer and his team conducted an in-depth evaluation of five advanced lighting control systems in a working office environment. The case study was designed to evaluate the capabilities of these advanced technologies and highlight their positive and negative attributes, instead of simply comparing one product with another. The evaluation was not only concerned with the energy savings performance, but other critical aspects of the system such as occupant satisfaction, installer experience, and overall system operation. The case study found: that the systems achieved an average energy savings of 63%, installers found the installation on par or easier than traditional lighting, and occupants expressed over 70% satisfaction with the systems. By highlighting these advanced control systems in an objective manner, this paper adds to the growing evidence in support of the use of advanced lighting control systems.

As designers and building engineers implement energy saving control systems it’s critical to understand occupants’ preferences prior to installation in order to maximize savings and occupant satisfaction. A study by Sara Gilani and William O’Brien found that users in perimeter offices preferred some level of manual control over their lighting systems in order to maximize available daylight. With this information, they conducted a study with vacancy sensors (manual-on / auto-off) installed in these offices and found that lighting electricity use was reduced by a factor of seven. Their study also highlighted the significant energy savings captured when using vacancy sensors compared to traditional occupancy-based sensors. They found that they were able to achieve 62% energy savings  after switching the existing, occupancy-based sensors with vacancy sensors. This insightful report emphasizes a point brought up in the paper by Parise et. al. in which designers must choose the most appropriate control because simply having controls is not always enough.

Michelle Davidson’s evaluation of a warehouse case study where an advanced lighting control system was installed highlights the significant impact a lighting control system can have on the entire operations of a business. Despite the 200,000 sf facility being only 3-years old, its lighting fixtures were consuming over 1.3 million kWh each year. With the implementation of LED fixtures and an advanced lighting control system, the facility was projected to save roughly 500,000 kWh per year, however, since 2013 the building has averaged an annual consumption of 300,000 kWh – exceeding their savings projections. The lighting control system has also enabled the company to monitor space utilization, which ties into their HVAC system to optimize heating and cooling schedules. The lights are also able to track equipment usage, which has improved maintenance schedules and improved the efficacy of their operation. In sum, as technology continues to advance, lighting controls offers unique opportunities for businesses that extend beyond energy savings.

II. Dynamic Lighting & Biological Cycles

Utilizing a controls-based lighting system is a great way to save energy, but the effects of good lighting on our biological processes extends much further than we typically think. Recent medical and biological research has consistently demonstrated that light entering the eye, apart from visual effects, also has non-visual impacts our biological processes. As a result, good lighting has a positive impact on our sleep quality, health, well-being, and alertness. In a paper by van Bommel et. al. they highlight the biological significance of using cool white light. They found that when using cool white light at moments that biologically active lighting is required can promote healthier work environments – boosting the well-being of employees. They also found that using cool white lighting allows individuals to dim the lights, while still maintaining a desired visual environment, ultimately leading to energy savings.

III. References

Primary Research
  • Davidson, Michelle. 2016. “Case Study: IoT Lighting System Cuts Energy Costs, Improves Productivity.” Network World. Network World. July 26. https://www.networkworld.com/article/3099682/case-study-iot-lighting-system-cuts-energy-costs-improves-productivity.html.
  • Gilani, Sara, and O’Brien, William. 2018. “A Preliminary Study of Occupants’ Use of Manual Lighting Controls in Private Offices: A Case Study.” Energy and Buildings 159. Elsevier B.V: 572–86. doi:10.1016/j.enbuild.2017.11.055.
  • Myer, Michael. 2018. “Evaluation Of Advanced Lighting Control Systems In A Working Office Environment”. Gsa.gov. https://www.gsa.gov/cdnstatic/Applied_Research/PNNL_Evaluation_Advanced_Lighting_Controls_11-2018.pdf.
  • Parise, Giuseppe, Martirano, Luigi, and Di Ponio, Simone. 2013. “Energy Performance of Interior Lighting Systems.” IEEE Transactions on Industry Applications 49 (6). IEEE: 2793–2801. doi:10.1109/TIA.2013.2263114.
  • van Bommel, Wout J.M. 2006. “Non-Visual Biological Effect of Lighting and the Practical Meaning for Lighting for Work.” Applied Ergonomics 37 (4). England: Elsevier Ltd: 461–66. doi:10.1016/j.apergo.2006.04.009.