The Cost of Keeping the Lights On

The proportions of energy use and GHG emissions attributable to street lighting ranges among BC communities. For instance, street lighting accounts for 15% of energy use, 38% of energy costs, and 6% of GHGs emitted by the City of Nanaimo’s civic infrastructure [1].

In the District of Squamish, street lighting accounts for just 3.5% of energy use and 1% of GHG emissions [2]. Assessing the potential to reduce energy costs and GHG emissions through retrofitting street-lights is a smart move for local governments to make.

Retrofitting – A Bright Idea

Local governments in British Columbia, in cooperation with BC Hydro, have already had tremendous success retrofitting traffic lights: Between 2004 and 2006, 98% of light-controlled intersections in BC were converted to Light Emitting Diode (LED) technology, saving $1.6 million annually in electrical costs [3].

Now, retrofits to street lighting are becoming increasingly common across North America. Street-light retrofitting strategies include:

• Ensuring that street lighting standards do not greatly exceed minimal requirements established by the IESNA.
• Ensuring that light is not wasted illuminating the night sky. New fixtures are often designed to prevent light from shining upwards. This strategy not only saves energy but also lessens light pollution. The “cobra head” street lighting fixtures found in many communities are notorious light wasters.
• Using more efficient light sources. New street lighting technologies often consume 40-50% less electricity, and have longer life span than conventional bulbs. This saves local governments on both energy costs and maintenance.    

B.C.'s local governments can learn from the City of Calgary’s comprehensive street lighting retrofit, which featured “flat lens” fixtures that direct light only downwards. By employing these bulbs, Calgary has nearly halved their street lighting electrical consumption, and saves $1.7 million in electrical costs annually [4].     

LED Lights – The Cutting Edge

Light Emitting Diode (LED) lights are showing promise in reducing street-light wattages to new levels of efficiency. For instance, the City of Ann Arbor, Michigan, has replaced its 120W incandescent bulbs in decorative downtown street lights with 56W LED lights. The retrofits cost $630,000. This will yield $100,000 in annual electrical savings, as well as maintenance savings, providing a rapid return on investment [5].

LEDs are not yet economical in all contexts. For example, the City of Vancouver has long standing policy of lighting its streets to minimally accepted standards defined by the IESNA. This policy has allowed Vancouver to save on energy and reduce light pollution. LEDs do not yet affordably produce as much illumination as other lighting technologies.

Because Vancouver’s street lighting fixtures are currently well spaced, retrofitting using LEDs would require installing new fixtures to keep lighting levels to acceptable levels. Installing new fixtures would be expensive, and keeps an LED retrofit from being cost effective using current technology [6]. However, cities that currently go above accepted minimum standards and provide a great deal of lighting may be able substantially reduce energy consumption by using LEDs. The opportunities for switching to LEDs should be assessed on a case-by-case basis. 

Benefitting from Experience – Using an ESCO

Local governments may procure an Energy Services Company (ESCO) to assess and undertake retrofits. Many ESCOs have experience conducting street lighting retrofits, and are well positioned to suggest optimal strategies in a municipalities’ specific context. ESCOs can provide guaranteed energy cost savings, using performance contracting, making it simpler to finance retrofits.

Local Governments Light the Way

A Well-Lit City

In 2007, the City of Welland, Ontario, population 50,000, initiated a comprehensive street lighting retrofit. Existing 175 watt high-pressure sodium lamps were upgraded to 90 watt LEDs. Upon completion of the retrofit, the city is projected to save 47% of its street-lighting electricity costs, and 75% of maintenance costs, for a combined annual savings of $309,000 [7].   

In Kelowna, The Sun Even Shines at Night!

The City of Kelowna has launched a solar powered lighting project, assisted by funding from the federal government and Carmanah Technologies Corporation. By September 2009, Kelowna will install 100 solar powered LED fixtures to light public spaces. These fixtures require no connection to the electrical grid, and are powered entirely by renewable solar energy. [8,9]

Calgary Keeps the Lights Down

Between 2002 and 2005, the City of Calgary retrofitted their 37,000 street-lights with more efficient flat-lens high-pressure sodium fixtures. Unlike conventional “cobra head” lighting fixtures, flat lens fixtures prevent light from wastefully entering the night sky. Having reduced their lamp wattage from 200W to 100W on residential roads, and from 250W to 150W on collector roads, Calgary saves an estimated $1.7 million annually in electrical costs. The retrofit’s costs will be paid off by 2012. [4]

[1] City of Nanaimo. (2007). Corporate Climate Change Plan: Energy and Emissions Management. 

[2] The Sheltair Group. (March 2007). Bridging to the Future in Squamish, BC: Energy & Greenhouse Gas Emissions Baseline & Forecast, 2005-2025. The District of Squamish.

[3] BC Hydro. (August 2004). Traffic Intersections.

[4] The City of Calgary. (April 2008). EnviroSmart Streetlight Retrofit.

[5] Tom Gantert. (October 2007). City to be 1st in LED lights. AnnArbor News.

[6] Phil Wong. (September 10th, 2008). Superintendent, Electrical Design and Support Services. City of Vancouver. Personal Communication.

[7] Brian Owen. (August 2007). Welland is Well Lit with LED street lighting. LEDs Magazine.

[8] City of Kelowna. (September 2008). Solar Powered Lighting Project. City of Kelowna.
[9] Anthony Tisot. 2008. Committed to Renewable Power: Kelowna goes gren with solar powered area lighting. Carmanah Technologies Corporation.