LED in City Street Lighting, Councillor Jan Harder, City of Ottawa
In the early 1960s, Light Emitting Diode (LED) technology was introduced to the world. Originally emitting red light, it took was used for electronics such as calculators and even watches. In the 1970s the use of this relatively inexpensive technology was a game-changer as it began replacing incandescent bulbs in electronics. The result made electronics a lot more affordable for the average consumer.
Blue LED lighting was discovered in 1992, allowing it to be used for lighting. One of its earliest application was in flashlights. Using less power, the bulbs on flashlights never had to be replaced. After LED technology made its way to homes, it was in 2010 that it came to dominate outdoor lighting.
Since 2016 the City of Ottawa has led a Street Light Conversion program whereby the City and Envari Energy Solutions Inc., a subsidiary of Hydro Ottawa (formerly Energy Ottawa) partnered to convert 58,000 streetlights. At the end of April 2019, 40,000 street lights had been converted. According to the City’s Transportation Department, “the converted fixtures are achieving on average 64 per cent energy savings with an associated cumulative energy reduction of approximately 21,700,000kWh, or an energy cost saving of approximately $3.15 million.” This energy efficiency represents a reduction of 1,843 metric tonnes of greenhouse gas, an incredible benefit as we race to reduce the impact of climate change on our planet.
Environmental benefits aside, there are many other advantages to converting to LED lights. The typical lifespan LED lights are 4 to 5 times longer than other types of light which also reduces maintenance costs and carbon footprint (less waste). As well, each light can be customized to offer the optimum illumination levels for each individual street. Enhanced monitoring through daily reporting of malfunctioning street lights reduces the reliance on resident reporting and response time. Envari built a wireless network across the City and each LED streetlight to report its status, communicate in real-time, and be dimmed as designed, providing the City with full control. The Transportation Department also reports that “LED street lights also enhance nighttime visual acuity because of an increased colour-rendering index making it easier for motorists to identify roadway hazards.”
There are critics of LED street lighting including the American Medical Association (AMA). The AMA has stated that the intensity of LED lighting can disrupt the circadian rhythms of people which in turn can affect sleep and all of the effects caused by lack of sleep. The City of Ottawa of Ottawa has taken the steps to ensure that the LED fixtures have “similar colour temperatures to the old fixtures, with lights on residential roads having a warmer colour temperature than those on main arteries.”
The project has completed retrofits on 51 arterial roads and 90 per cent of the urban areas of the City, including parts of Barrhaven, Kanata, Orleans and Old Ottawa. The project although focused on roadway safety, has also maximized opportunities for energy and maintenance cost savings. The project is expected to end mid-2020 – on time and on budget!
Below are some of the benefits of LED street lighting:
- LED lights depreciate at a much slower rate than other alternatives
- They are light-emitting diodes, so they do not have filaments or burn out quickly (they have incredibly long lives)
- No toxic chemicals like mercury
- Reduced maintenance costs
- Long lives mean these are great for areas where it’s inconvenient or difficult to replace bulbs when they die
- Do not produce a lot of heat
- Consume little energy
- A wide, consistent light pattern
- Fewer hotspots (and then areas of dark spots)
- Improved colour rendering comparative to sodium lamps
- Environmentally- and Fiscally Friendly!