In the days, weeks, and perhaps months post Superstorm Sandy, it has become evident that the grid we rely on for virtually everything is incredibly susceptible to unkind acts. In this case it came from Mother Nature. It is in these moments that the simple things we take for granted, such as lighting, are not so simple to restore.
The utility companies struggled to restore services, but what if fundamental needs like lighting could be upgraded to disconnect and be maintained as an “island” (off-grid use) until normal service is restored? Public lighting, buildings, and communities can be disconnected to protect them from systemic failures and provide power to run essential services, mitigating the impact of catastrophic events. Technologies exist today that will allow for this, but it requires a wholesale change in thinking, preparation, and public-private partnership.
Lighting can direct the path to recovery. Rather than evaluating lighting solely on the utility costs of power (kilowatt hour) and its efficiency to produce light from energy consumed (watts/square foot), we need to add an additional metric: reliability. Lighting’s reliability is dependent on the power’s quality and surety. Issues include not enough power, peak demand cutbacks, power blackouts and brownouts, rising costs, decreasing quality, increasingly negative consequences of extreme weather, and the threat of terrorism—foreign and domestic.
LEDs (light-emitting diodes) are generally thought of as being energy-efficient, but there are some basic characteristics to this technology that makes it ideally suited for adding reliability to a lighting system.
- In addition to being efficient, they have a very low power draw, which is important in times of power outages. By reducing the power draw, you can do more with less as well as extend the life of emergency backup systems such as batteries and generators.
- LEDs offer controllability—getting lighting where you want it, when you want it. They can be controlled by simple, yet effective digital controls that deliver the right amount of light, at the right place at the right time.
- LEDs are natively direct current (dc), allowing them to integrate with alternate sources of dc power which enables islanding.
While some electrical infrastructures may not survive the fury of a hurricane, street lighting that is based on alternate energy could be independent of the grid. In developing countries, this is already happening because the technology is leap-frogging the grid’s very existence. Much like the rapid adoption of cell phones, solar street lighting is becoming popular because it does not require infrastructure. With solar panels mounted to individual LED luminaires and the ability to store many days’ worth of power, this allows villages to have light in the absence of a grid or even in a natural disaster.
In the case of Sandy, while many street lights were ripped out of the ground, many were dark because of power outages. If these lights could work off alternate energy they had collected and stored, the impact it could have on recovery efforts would be immeasurable. Because LED technology inherently requires less energy than traditional technologies and lends itself to dc power, municipalities could install solar or other backup power systems, which would allow first responders to have lighting and get to those in need. While not all street lighting may be operable, entire cities and towns would not have to be in the dark for days or weeks.
There are other scenarios that could be implemented gradually. For example, every other street pole in areas that are central to disaster relief—such as hospitals or shelters—could be replaced with battery backup systems. Municipalities could do several poles a year, eventually covering their entire town or city, without large, costly upfront investments. If funding is a challenge, often there is affordable private financing for these systems. The other advantage to these battery backup systems on low-powered LED lighting is a modular approach that could include adaptive dimming. This would not require full power to give citizens a sense of safety or comfort. Even dimmed lighting would give people a sense of hope while preserving energy and acting as beacons of light for first responders.
The controllability of LEDs tied into a centralized software system not only allow administrators to get lights on where they are still available, but also to see exactly where the lights are out. This gives them an idea of what areas were hardest hit and where they might want to direct first responders. Because these poles are islanded, they can also be used as communications beacons—distributing text information for emergency follow up or acting as a meeting place for those affected. By extension, an islanded lighting pole may be dimensioned to provide enough local energy storage to periodically collect low bandwidth texting messages from cell phones and periodically transmit them to other communication networks, replicating a telecom site-cell but on a power diet. This would allow people to contact first responders and loved ones in the event of outages.
Another extension of this modular approach is allowing the LED lighting system’s backup power to energize cameras that are used for monitoring traffic, once again allowing city administrators to get a bird’s eye view into the situations and help guide first responders.
This approach can be applied to everything from your home to an office or apartment building. For instance, new legislation in New York City indicates that buildings be retrofit with more energy-efficient systems. This is a great opportunity to upgrade to LED lighting systems that use substantially less energy, while having the ability to operate on dc battery power, fuel cells, or as part of an in-building microgrid.
The ultimate asset of LED technology is that when it is not being islanded, it can still be used smartly. Because of its low energy draw and controllability, LEDs will use up to 80 percent less energy and provide better quality of light.
The investment is not only in energy-efficiency, but also a stepping stone to better position communities in the event of a disaster.
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