Urban areas have not only crowded streets during the day, but also at night. Lampposts are therefore placed in high frequency on the streets of big cities. The energy use of these street lights in the US is annually the same as the energy use of 1.9 million households and they generate greenhouse gas emissions equivalent to 2.6 million cars. There is thus a big opportunity in improving these streetlights in order to create more sustainable cities.
Los Angeles introduced the “The LED Streetlight Replacement Program” four years ago, and already replaced more than 140,000 existing street lights by LED’s. This resulted in a reduction of 63.1% of energy use and an decrease of the carbon emissions of 47,583 metric tons a year. Surprisingly, the total cost of the project was lower than expected, because of the tremendous price decline from ±$700 to ±$300 a fixture.
This project in LA can easily be copied in all urban areas in the world. There are even more technologies available, besides the use of the LED light, to make lampposts more sustainable. Sensors can be implemented to turn off the LED lights when streets are empty. It is also possible to create wifi-hubs in the lampposts, or implement sensors that measures the amount of CO2 and the noise levels in the surrounding area.
Turning off the lights when streets are empty will result in an even bigger reduction of energy use and carbon emissions. This is not only a big advantage for the energy and environmental aspect of sustainable development, but it is also advantageous for the economics of a city as it saves a lot of money on its energy bill. The reduce of carbon emissions will in the end result in an improvement of a city’s air quality, which improves the health of citizens. The placement of the LED street light in slum areas of the city will finally also lead to an improvement of social equity and safety, since brighter streets decrease the amount of violence.