Energy & Environment

San Francisco Tests a Streetlight That Thinks for Itself

The city is hoping that remotely controlled lights connected to mini-grids can cut maintenance and energy costs as well as CO2 emissions.
by | September 2012

The “smart city of the future” idea means different things to different people. In San Francisco, it means streetlights. City officials there are hoping that by connecting streetlights to mini-grids, allowing them to be monitored and controlled remotely, they can cut maintenance costs, energy expenses and CO2 emissions.

That connectivity would allow the city to dim streetlights in areas where they’re not needed. If one part of town is socked in by fog, the lights could be brightened. If traffic in another neighborhood is particularly light on a Wednesday night, the lights could be dimmed accordingly. Being smarter about light levels saves energy and money, says Mary Tienken, a project manager at the San Francisco Public Utilities Commission. Additionally, the city would know instantly when a particular light is damaged or needs replacement. “As opposed to getting a report from a citizen in a nebulous control system, it will be automatic,” Tienken says.

Here’s how the pilot project will work. Nodes attached to each streetlight will monitor the light’s power consumption and relay that information to the utility. Using that data, the city can monitor conditions, remotely control the streetlights or set timers or automatic indicators for turning the streetlights on or off. Down the line, Tienken says, additional motion sensors could detect things like vehicle and pedestrian traffic, meaning the city could adjust to lighting needs in real time. Along with a parallel project that’s converting street lamps from high-consumption sodium bulbs to LED fixtures, the city expects to cut its lighting bill in half.

The streetlight project is part of a larger pilot program the city is currently investigating, which would ultimately attach several services to a unified wireless system. Such a program, which is only in the planning stages, would let the city monitor everything from vehicle charging stations to parking meters to traffic cameras, and adjust city services accordingly. “This would solve not just our individual interest” in cutting streetlight energy consumption, says Tienken, “but [it would also start] solving a larger issue” of delivering services more efficiently.

“We’re definitely moving forward with an ambitious plan to make our city smarter and more efficient,” says utilities commission spokesman Charles Sheehan.


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