Energy Saving Road Lighting in Norway

May 12, 2023 8:16 PM

Energy Saving Road Lighting in Norway. When traffic approaches, Norway’s auto-dimming roads get brighter. New LED lights dim to 20 percent when no cars are in the area. When a car drives by, the lights turn to 100 per cent.

This is useful for
a) saving electricity/carbon emissions;
b) reducing light pollution, which has harmful effects on wildlife.

posted by chariot pulled by cassowaries (24 comments total)

yes
posted by j_curiouser at 8:25 PM on May 12, 2023 [2 favorites]

Oh thank god they're doing it with radar.

With the latest fad of using off-the-shelf cameras for stuff, I was worried they might be sensing the headlights and, well... that would not have been smart.
posted by tigrrrlily at 8:28 PM on May 12, 2023 [4 favorites]

great

it would be nice if more vehicles had auto-dimmers too
posted by ovvl at 9:11 PM on May 12, 2023 [3 favorites]

From the embedded video it looks like those lights go to 100% brightness one at a time, presumably triggered by the radar on the same pole as the light. From a road safety point of view I'd prefer to see the poles talk to each other and turn on three or four lights ahead of the pole that sees the car, with the most distant lights ramping their brightness up a little more slowly. This would give drivers more time to react to wandering m00ses and whatnot as well as reducing fatigue and distraction from driving into visibly varying lighting.

Great idea, though.
posted by flabdablet at 11:28 PM on May 12, 2023 [4 favorites]

I have proposed this to walking partners countless times. We always figured that the maintenance burden and risk of failure made this a non starter.

I'm delighted to see this, and hope they learn a lot and iterate effectively. I'd love to see this everywhere.
posted by constraint at 11:32 PM on May 12, 2023 [7 favorites]

I'd prefer to see the poles talk to each other and turn on three or four lights ahead of the pole that sees the car,

If you watch through to the end of the video, they explain that the lights do exactly that. They say it’s not even perceptible to the drivers that the lights are coming on for them, since it happens so far in advance and allows for illumination a long way ahead.
posted by ourobouros at 11:39 PM on May 12, 2023 [19 favorites]

Started to build this maybe 20 years ago as LED prices got cheap enough .... the wireless stuff to get the lights to talk is easy, the hard parts are:

- supporting cyclists and pedestrians (you want the lights to follow a pedestrian down the street to provide them with a bubble of lit safety) so your sensors need to handle everyone, and
- intersections, you're lighting up the road ahead of the car, you have to light up all paths out of an intersection
- not pissing off the neighbours (this is easier) you want to turn lights on/off gradually, niot flicking them on/off
posted by mbo at 1:22 AM on May 13, 2023 [3 favorites]

I'd have thought with intersections, the simple solution would be to not dim them, similarly to some places that switch them off for part of the night, but keep them on at intersections, being the most likely site for a (vehicle/pedestrian) collision.
posted by Dysk at 2:44 AM on May 13, 2023 [2 favorites]

i wanna see an aerial view!
posted by lapolla at 3:54 AM on May 13, 2023 [3 favorites]

This seems cool! And limits light pollution. I am curious what effect the lights going up and dimming might have on wildlife.
posted by tiny frying pan at 5:16 AM on May 13, 2023 [3 favorites]

I would speculate that the effect on wildlife is comparable to the effect of the lights of passing cars — some transient artificial light is unavoidable if there are nighttime users of the roadway, but this sounds like a big improvement.
posted by Songdog at 6:03 AM on May 13, 2023 [7 favorites]

I have proposed this to walking partners countless times. We always figured that the maintenance burden and risk of failure made this a non starter.

IDK specifically about highway implementations but when doing walking paths and parking areas everything but the most basic of commercial fixtures includes photo cells and variable light levels controlled by motion sensors; at least optionally. Some of them allow time of day control as well (IE: all lights in a parking lot serving a business open to 10pm might have lights that dim to 50% during business hours and 10% after 10:30pm but individually brighten to 100% when people approach). Or you might vary the brightness by location to encourage customers to usecertian parking or entrances. All those features are included in typical 50k hour warranties that covers the light emitter.

Interconnecting the lights wirelessly is easy in retrofits however leaves open the possibility of them being taken over by bad actors but hard wiring options exist that are relatively resistant to drive by attacks.
posted by Mitheral at 6:33 AM on May 13, 2023 [3 favorites]

But there would be a much different effect than just headlights I would think because it illuminates top down and is in a permanent location...thinking of things like lightning bugs, bats, etc. Hmmmm.
posted by tiny frying pan at 6:39 AM on May 13, 2023 [1 favorite]

I read this as “Road Lightning” and was thinking that would be a cool way to power roads. I was disappointed.
posted by misterpatrick at 8:08 AM on May 13, 2023 [1 favorite]

If they did this to the street light in front of my house I would be driven mad in very short order.
posted by 3j0hn at 8:19 AM on May 13, 2023 [4 favorites]

- supporting cyclists and pedestrians (you want the lights to follow a pedestrian down the street to provide them with a bubble of lit safety) so your sensors need to handle everyone

Isn’t this partially mitigated by those people not needing anywhere near as much lighting? Cars are terrible for night vision with interior lights, oncoming headlights, and much higher vehicle speeds make your reaction time thresholds more aggressive. 20% seems plausible on paved roads in the absence of cars.
posted by adamsc at 9:18 AM on May 13, 2023

The five-mile stretch of energy-saving street lights saves 2,100 kWH per week, which would amount to approximately 21 hours of ironing, or four hours of watching TV on a plasma screen.

Unless this is Frank's 2000" TV, this doesn't sound right.
posted by justkevin at 9:44 AM on May 13, 2023 [4 favorites]

Isn’t this partially mitigated by those people not needing anywhere near as much lighting?

Yes - this night-hiking pedestrian and midnight cyclist only requires minimal lighting, as long as my night vision isn't compromised by oncoming headlights. Therefore, IMO this system is over-engineered, except for drivers.

I do like the idea of glow-in-the-dark bikepaths.
posted by Rash at 9:50 AM on May 13, 2023 [3 favorites]

An old school 50" plasma display often hit 4-500 watts if calibrated for a lit room. So looks like they they made the common error of confusing W and kW.
posted by Mitheral at 4:39 PM on May 13, 2023 [1 favorite]

I'd have thought with intersections, the simple solution would be to not dim them, similarly to some places that switch them off for part of the night, but keep them on at intersections, being the most likely site for a (vehicle/pedestrian) collision.


It's not so much just the intersections themselves (which arguably might be lit all the time) but the lights past the intersection in all possible directions the car might end up taking - you have to bring the lights up far enough ahead that it's not distracting the driver, and slowly so the flashing lights don't annoy the people living next to them (which makes them even further away so that the lights are all the way up by the time the car needs them).
posted by mbo at 6:24 PM on May 13, 2023 [1 favorite]

If you watch through to the end of the video, they explain that the lights do exactly that. They say it’s not even perceptible to the drivers that the lights are coming on for them, since it happens so far in advance

Seeing lights brighten in the distance, with off-road stuff suddenly revealing itself accordingly, was clearly perceptible to me in the driver's-view sections of that video. As a driver I'd find that distracting, and I'd also be distressed that there could be e.g. animals in the distance I'd be getting less time to react to than fixed lighting would give me.

Some of that perception might be due to the video being presented in fast motion, unless Norwegian drivers really do handle slippery conditions at speeds that terrifying. But if the poles are indeed already talking to each other, it wouldn't take much to program them so that brightness begins its ramp-up up on more distant poles than apparently happens at present. This would also make it feasible for each pole to ramp up and down much more gently than they currently seem to, which would be kinder to people who live near them.
posted by flabdablet at 8:46 PM on May 13, 2023 [1 favorite]

it would be nice if more vehicles had auto-dimmers too

Gods, yes, this. It seems that, with the advent of ludicrously bright LED headlamps, carmakers have voiced a collective “fuck it” when it comes to actually aiming the things so they don’t blind oncoming motorists. American pickup trucks are the worst offenders, imho.
posted by Thorzdad at 7:28 AM on May 14, 2023 [2 favorites]

I'm not sure this is a good idea for walking paths, parking lots, etc. It would be far too easy for someone to wait in the shadows and they'd know when someone's approaching as lights in the distance start to come on and then go off again as the person passes under the lights and comes nearer. I know I'd be really hesitant to walk down any path that's like that.

That said, where I live the street lights are turned off at midnight (to save money), so I've arrived at the Tube station late at night (the trains run until just after 1am during the week and all night at weekends) and it is literally pitch black and I've had to use my phone torch to find my way to the car park. When this hairbrained scheme was started in a few years ago, the number of robberies, assaults and sex crimes increased rapidly. The police response was "we advise people to stick to well-lighted paths". Now if I know I'm going to be in town late I'll drive to a station further down the line in a borough where they don't turn off the lights, so it'll be safer to get to my car on my way home.
posted by essexjan at 12:30 PM on May 14, 2023 [1 favorite]

Thorzdad: apparently some helpful tech on this front was only recently approved by the NHTSA: https://youtu.be/c2J91UG6Fn8?t=14m06s
posted by Cogito at 10:46 PM on May 14, 2023