On a quiet weeknight next to Quidi Vidi Lake, there were only an handful of cars zipping through the pools of light underneath the streetlights.
The drivers probably don’t notice that it’s a new row of taller telephone poles, or that the poles have been moved back away from the curb. They probably also don’t notice that the profile of the streetlights has changed; that, instead of being the traditional arced high-pressure sodium light mounting known in the industry as the “cobra-head,” the lights are flatter and broader.
One thing the drivers might have noticed is that 18 of the streetlights are a different colour — white instead of the familiar orange — or that they seemed brighter.
What they almost certainly
didn’t see is the savings.
One small string of the lights — using light-emitting diodes (LEDs) instead of high-pressure sodium — could be about to drastically cut the city’s electric bill. And those savings, both in power use and in power bills, could help across a province that’s currently forecasting an electrical power shortfall in just a few years.
The city has 11,361 streetlights — and, in 2010, budgeted nearly
$3.8 million to keep them serviced and lit.
Province-wide, there are many, many more.
Why make the change? Try this information from a 2010 Science Daily article:
“Engineers in the Mascaro Center for Sustainable Innovation based in (the University of Pittsburgh’s) Swanson School of Engineering compared LED streetlights to the country’s two most common lamps — the high-pressure sodium (HPS) lamps found in most cities and metal halide lamps akin to those in stadiums-and the gas-based induction bulb, another emerging technology billed as bright and energy efficient. The team reported that LEDs may carry a formidable price tag, but in comparison to HPS and metal halide lamps consume half the electricity, last up to five times longer, and produce more light.”
(Interesting, the study also points out that Pittsburgh has four times as many streetlights as St. John’s, more than 40,000 streetlights, yet curiously pays just slightly more than we do, US$4.2 million, for their electricity and servicing. But that’s another column.)
Scores of U.S. cities are in
the midst of making the LED changeover, using U.S. federal government stimulus money and expecting to see huge savings on their power bills.
Using less power
The numbers vary, depending on who you’re talking to — the range runs anywhere from 40 per cent to 80 per cent less electricity to run the new lights.
Some comparisons show high-pressure sodium lights using as much as 1,204 kWh a year, while comparable LED streetlights draw just 505 kWh — a lot depends on how far North (or South) you are, and how long your lights are on.
Use the 1,204-to-505 numbers in St. John’s, and a full retrofit could reduce electricity consumption by well over seven million kWh every year.
Convert that to the amount of power needed to run the lights for that period of time, and you’d end up with just under a megawatt of power. Not a huge number, perhaps, but far from insignificant.
Testing the numbers
A U.S. Department of Energy study on streetlights in Palo Alto, Calif., from June 2010 said, “Measurement results from the demonstration project show that LED luminaires produce more uniform light output than that of HPS and induction luminaires. LED luminaires also have much better cutoff on the curbside of the streetlight luminaire, resulting in significantly reduced light trespass onto residential properties. Of the three systems (induction, HPS and LED), the LED used the least energy (44 per cent reduction compared to the baseline HPS).”
Another U.S. Department of Energy study in Portland, Ore. — where streetlights were operational for 4,380 hours — saw regular sodium lights using 525 kWh of electricity, with LED lights using just 233 kWh. That’s a 56 per cent decrease.
There are streetlight manufacturers that argue you can recoup the cost of new LED lights in as little as 17 months — but at the moment, that may be hopelessly optimistic.
U.S. Department of Energy reports say the payback could take as long as a decade, but it would come.
Not only that, but there are other savings as well. LEDs have a 10 to 15-year lifespan, compared to three to five years for high-pressure sodium — that means fewer hours replacing lights, and fewer new lights to purchase.
The LED lights can also be set for varying — and changing — levels of light at different times through their nightly cycle, something high-pressure sodium simply can’t do, and something that can save even more in power costs.
They can even be equipped — for an increased capital cost — to generate some of their own power using solar generation.
The city says The Boulevard project is expected to cut electrical use, per light, by around 59 per cent — the first units are going in to test maintenance claims, and apparently, there will be around 300 of the lights installed.
Speeding it up
Since electricity use in this province is about to reach some sort of crisis point, you might be thinking things could move a little faster.
A forward-thinking provincial government, for example, might be willing to front the money to Newfoundland Power for streetlight purchases and retrofits, and have municipalities pay it back from municipal savings in reduced electrical bills.
A forward-looking government might also look at smart meters, at off-peak power pricing and at a feed-in tariff system that would pay smaller producers to get money for putting power back into the grid.
Just like LED streetlights, those are being tried in many other jurisdictions.
Maybe if we did that, a static-sized or shrinking, aging population wouldn’t be increasing its electrical consumption every single year — and wouldn’t need to take on billions in new debt and massive power rate hikes to make up for an electrical power shortfall.
Conservation — what a concept.
Russell Wangersky is The Telegram’s
editorial page editor. He can be reached by email at email@example.com.