Lately my husband and I have been noticing random street lights around the city have been turning violet. I am unsure whether it feels eerie or magical, distracting or fantastical. Yellow and white are typical, but purple? Is this a requested item by certain patrons? Does it cut down on light pollution? It feels like they aren’t quite as effective, but maybe research shows differently.
I decided to dive into it further. Have you also noticed these lights? My mind began spewing so many questions all of a sudden.
Why are some street lights purple?
Short and sweet: manufacture defect that effects streetlights nationwide.
A statement from Acuity as found from South Florida’s Local 10 news is “The referenced ‘blue light’ effect occurred in a small percentage of AEL fixtures with components that have not been sold for several years. It is due to a spectral shift caused by phosphor displacement seen years after initial installation. The light output is in no way harmful or unsafe.”
Florida Power & Light states “We are aware that some LED streetlights are emitting a purple hue rather than the standard white light. Most importantly, these streetlights are safe and will not impact visibility. The purple hue is the result of a manufacturer defect and is impacting streetlights nationwide.”
How much does it cost to change a street light?
On average electricity costs are around $0.12 kW/h on some sites and others say $0.10 kW/h. If the bulb is 100 W and runs for 12 hours a day 100 x 0.12/1,000 = $0.012 an hour x 12 hours = $0.144 per street light per day. It gets bigger and bigger the more street lights you have. Think about how many there are on an expressway, for example.
Who is in charge of changing street lights?
It is the job of the Municipal Corporation of the city.
How often do street lights need to be changed?
Each light runs about 4,000 hours a year, but it takes them 6-7 years before burning out. However, the high efficiency LED lights last 100,000 hours. This means they should last about 25 years!
Conspiracy theories?
Of course there are. Alien signal? Acknowledging order and power? Letting scanning take place? Controlling brains with optigenetics, i.e. light.
Personally, I would assume they use the purple lights most in lower income areas because they will probably get less complaint calls about them. Simply could be just a lower priority neighborhood.
All I know is I’ve been noticing them, it could be an error, or it could be covert in intention.