Shedding light on sustainability

Victoria’s switch to a new form of street lighting will be good for the environment, as well as the taxpayer’s wallet. This fall, the city will start replacing its 6,500 streetlights with LEDs, which last much longer and consume less electricity than the high-pressure sodium lights now being used. The changeover is expected to take about 18 months.

Fraser Work, Victoria’s director of engineering, says streetlighting uses nearly five million kilowatt hours of electricity a year at a cost of $500,000. The new lights will bring 45 to 55 per cent energy savings, as well as much lower maintenance costs because of the long life of the LED lights. The $2.1-million program is expected to pay for itself in nine years.

LEDs (light-emitting diodes), unlike incandescent bulbs, don’t use filaments that can burn out. They also operate at much lower temperatures and are suited to on/off and dimming controls, so that the light produced is better matched to when and where it is needed.

Any measure that reduces energy consumption is good for the environment, as that means less greenhouse-gas emissions and other deleterious effects from power generation.

Light itself is a pollutant. Scientists have long complained about how artificial lighting interferes with astronomical observations. That’s one of the reasons large telescopes are often situated in remote regions — to get away from the glow of streetlights and other urban illumination.

But there’s more at stake than getting a clear look at the stars. When we light up the night, we interfere with natural cycles that have evolved to work with the predictable pattern of day and night. Migrating birds are confused by city lights; such things as mating processes and hunting patterns are disrupted. Nocturnal animals wake up when they should be sleeping; diurnal animals see lights burning and think it’s still daytime.

Human health is also affected, as too much light at night is tough on sleep habits.

And yet we need lighting for safety and to make it easier to get around after the sun goes down. The trick is getting enough to be useful, but not so much it causes problems. LEDs make it easier to tailor the amount of light produced to the amount needed.

Also, the lighting fixtures are designed to direct the illumination where it is needed, not up in the sky to interfere with astronomy and migrating birds.

The updating of Victoria’s streetlights coincides with the completion of the removal of toxic soil from Rock Bay. What’s the connection? Early street lighting in the city depended on the coal-gasification plant that dumped coal tar and other pollutants in and around Rock Bay. Some of the gas was used to provide street lighting for several years in the 1870s and 1880s.

Victorians were proud in 1883 to be one of the first Canadian cities to acquire electric street lighting, but that power was produced by a coal-fired steam plant that added to the pollutants produced by the gasification plant. It has taken until 2016 to remove the final vestiges of that early energy production.

Early Victorians weren’t aware that their illumination came at an environmental price. We know better now, and Victoria is doing something about it.