Smart Streetlights as a Tool for Grid and City Resilience

Written by Larissa Paredes Muse

Cities are one of the most significant sources of greenhouse gas emissions and also experience the hardest consequences of climate change, including catastrophic grid failures due to extreme weather events. Consequently, utilities and municipalities must work together and respond fast to restore the grid to a minimum operational state and guarantee the population’s safety and well-being.

To better identify the conditions and the nature of the damage, and therefore plan the infrastructure’s remediation at multiple levels, it is essential to work with reliable information. Street lighting is part of the electric grid and is considered to be a last-mile infrastructure, which is also vulnerable to the damages caused by those events.

The technological advancements enable the streetlights to collect data from the physical environment and to be controlled and monitored remotely, and it demands a connectivity infrastructure for data transfer, which can also be leveraged by the electric grid to improve resilience. This article will demonstrate at a high level how smart street lighting solutions can improve power grid connectivity and data-driven decision-making, especially in areas that are vulnerable to extreme weather events.

 

Smart Street Lighting

Smart street lighting can bring multiple benefits and opportunities to utilities, residents, the environment, and city and transit authorities. Beyond the classic benefits, such as energy efficiency, O&M optimization, cost reduction, and light controllability, smart streetlights can also reduce lighting disturbance and, consequently, mitigate the impacts of light on human health and the environment and improve roadway safety.

With the development of Information and Communication Technologies (ICTs) solutions for street lighting systems, utilities have more opportunities to improve grid management and share useful information across multiple teams. Similarly, the municipalities can benefit from the smart street lighting infrastructure by installing additional IoT devices for urban monitoring, taking advantage of the connectivity backbone. The data collected from those devices exponentially multiply the possibilities to integrate multiple urban services, optimize city management, and increase resiliency.

 

Smart Streetlights as a Tool for Grid and City Resilience

The term "resilience" can embody different definitions depending on which science is applied[1]. In general, resilience can be defined as the ability to return quickly to a previous state after being exposed to adverse conditions. In the context of cities and critical infrastructure, the term assumes new meanings:

• City Resilience is the ability a city has “to absorb, recover and prepare for future shocks (economic, environmental, social & institutional). Resilient cities promote sustainable development, well-being and inclusive growth”[2].
• Critical Infrastructure Resilience is “the ability to prepare for and adapt to changing conditions. This means being able to withstand and recover rapidly from disruptions, deliberate attacks, accidents, or naturally-occurring threats or incidents. Resilient infrastructure must also be robust, agile, and adaptable”[3].

 

Resilient Grids and Climate Adaptation

The electric grid is considered a critical infrastructure upon which the population relies for basic activities and even survival, in some cases. Being so necessary, the operators need to invest in resilience measures to avoid long-term power loss and other hazardous consequences of catastrophic failures.

In the face of increasing and recurring extreme weather events, cities and critical infrastructure operators must prepare to adapt, mitigate, and work to speed the recovery from the effects of climate change and become more resilient. For that, significant investments are needed to increase infrastructure robustness and resilience. With limited resources, cities and operators must prioritize investments in low-complexity deployments and yet effective solutions.

Climate-related resilience measures can be classified into Mitigation and Adaptation. According to the European Environmental Agency – EAA[4]

• Mitigation is defined as the measures that make “the impacts of climate change less severe by preventing or reducing the emission of greenhouse gases (GHG) into the atmosphere.”
• Adaptation can be understood as measures that anticipate “the adverse effects of climate change and taking appropriate action to prevent or minimise the damage they can cause, or taking advantage of opportunities that may arise.”

According to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change - IPCC, “both mitigation and adaptation are essential for climate change risk management at all scales”[5].

In the context of electric grid resilience, it is possible to affirm that mitigation comprehends “the proactive measures to prevent and reduce the causes and impacts of extreme weather events in the grid”[6]. It includes grid decarbonization measures such as energy efficiency, reducing fossil fuels dependency, and increasing the implementation of renewables and distributed energy resources - DERs. Adaptation is related to the reactive measures by “building resilience for the impacts that cannot be avoided [that require] hardening infrastructure”[6]. Elevating construction requirements to protect from higher speed winds and severe weather conditions is one example of grid adaptation measures.

Both preventive and reactive measures should be jointly taken to maximize grid resilience and reduce the time that the citizens are impacted by the grid failure. In other words, by adopting those measures seamlessly, the likelihood of lessening the impacts of extreme events will increase, and the time & cost for restoring the system will decrease.

 

Smart Street Lighting Resilience Approaches

In the face of extreme weather events, smart street lighting can increase grid and city resilience by significantly reducing energy consumption up to 80% [7] with the combination of LED luminaires and adaptive control systems. As a result, it can minimize carbon emissions, one of the main drivers of climate change. With less electricity generation demand, the avoided emissions can be significant considering the millions of streetlights worldwide, directly contributing to attenuating climate change effects. Following the aforementioned explained concepts, the enhanced energy savings through the implementation of smart street lighting can be considered a mitigation measure.

In addition to increasing wind load standards to reduce the severity of the damage, other adaptation measures can be adopted to minimize the impacts in the street lighting infrastructure, taking advantage of the new technologies.

Mitigation measures can also refer to the actions taken to reduce the hazard duration. The smart street lighting system can be designed to reduce response time after the event, using the data collected to drive decisions. Smart street lighting will facilitate failure identification by leveraging emergent technologies and improved grid connectivity. It can help reduce the impact and the duration of the effects that such events cause in the cities and citizens and increase the speed of recovery.

Respectively, metering sensors, geolocalization trackers, and advanced lighting controls embedded in the luminaires or poles can be configured to identify failures, determine the location of the damaged asset, and switch off or dim luminaires automatically in case of a shortage or life-threatening conditions.

More specifically, to speed up the response planning and repair crew dispatching, inclination sensors can be installed to detect the integrity of the streetlight infrastructure. In addition, environmental sensors can track microclimate patterns and other indicators that can be used to predict the severity of climatological events more precisely and determine when and where it is more likely to happen.

Using data to identify, plan, and prioritize recovery areas based on vulnerability and risk criteria can lead to more localized and precise restoration actions. The prioritization can be based on population density, hazardous conditions, or the number of essential services disrupted, such as hospitals and water treatment facilities.

 

Why Install Those Devices in the Street Lighting Infrastructure?

First, streetlights are convenient due to their privileged positioning throughout the entire city, which leads to a more democratic distribution of technology. Second, the complexity involved in installing those devices in the distribution lines is higher. The last-mile structures have more flexibility and lower complexity solutions, especially when some of those sensors can be easily installed in the newest LED luminaires through the NEMA 7-pin socket based on the ANSI/NEMA 136.41 standard.

Street lighting poles can also host larger devices such as network access points, compact environmental stations, sirens, and information panels to alert the population about the hazardous conditions prior to the event. In some cases, wind resistance, self-sufficient poles with solar panels, and energy storage can boost resilience in case of a catastrophic outage.

 

Conclusion

With the rapid development of the IoT, the opportunities to aggregate other functionalities to the street lighting infrastructure increased, and the possibilities to integrate multiple urban services, optimize city management, and increase resiliency have also amplified. Noticeably, the smart street lighting system will not be able to identify or resolve all the problems in the entire grid. As a result, the smart street lighting system needs to be integrated into the transmission and distribution monitoring system in order to enrich the data sources available to take more informed actions during emergencies. Nevertheless, smart street lighting can be a valuable tool to improve grid and city resilience, through the cited mitigation and adaptation measures, before and after extreme weather events.

 

References

1. Alexander, D. E. (2013). Resilience and disaster risk reduction: an etymological journey, Nat. Hazards Earth Syst. Sci., 13, 2707–2716, https://doi.org/10.5194/nhess-13-2707-2013.
2. Organisation for Economic Co-operation and Development - OECD. Resilient Cities. https://www.oecd.org/cfe/resilient-cities.html
3. U.S. Department of Homeland Security – US DHS. (November 2019). A Guide to Critical Infrastructure Security and Resilience. Cybersecurity and Infrastructure Security Agency - CISA. https://www.cisa.gov/sites/default/files/publications/Guide-Critical-Infrastructure-Security-Resilience-110819-508v2.pdf
4. European Environmental Agency – EAA. What is the difference between adaptation and mitigation? https://www.eea.europa.eu/help/faq/what-is-the-difference-between#:~:text=In%20essence%2C%20adaptation%20can%20be,(GHG)%20into%20the%20atmosphere.
5. Intergovernmental Panel on Climate Change – IPCC (2014). Fifth Assessment Report of the Intergovernmental Panel on Climate Change. https://www.ipcc.ch/site/assets/uploads/2018/02/WGIIAR5-Chap20_FINAL.pdf
6. Bahramirad, S. (2021, September 28). Climate Adaptation & Resilience Webinar. Quanta Technology. https://quanta-technology.com/event/climate-adaptation-resilience-webinar/
7. Gagliardi G, Lupia M, Cario G, Tedesco F, Cicchello Gaccio F, Lo Scudo F, Casavola A. Advanced Adaptive Street Lighting Systems for Smart Cities. Smart Cities. 2020; 3(4):1495-1512. https://doi.org/10.3390/smartcities3040071

 

 

This article edited by Jorge Luis Angarita.

To view all articles in this issue, please go to February 2022 eBulletin. For a downloadable copy, please visit the IEEE Smart Grid Resource Center.