Energy saving auto dimming street lights

[Andrew Gabriel]

Norway - At highway 155 in Nes i Hole, 220 radars have been installed
on light poles. They detect oncoming traffic and adjust the strength
of the light. By doing this, the 9 km/5.5 mi stretch saves a whopping
2100 kWh per week. The extra investment will break even after just 4.5
years.

In the UK they save even more money by simply not lighting the roads.

There has been a trend to switch off the lights on rural roads/motorways
outside busy periods. In some cases, they have been permanently switched
off. Also, many have been changed to delay switch-on until much lower light
level than used to be the case.

In UK, many of the new LED streetlamps which are controlled by mesh
networks have their light level set remotely, and automatically adjusted
at different times of night. They can be adjusted for once-off events
too, when a council is prepared to pay extra to have them on brighter for
longer if there's a local event resulting lots of people around later.

I am not aware of occupancy sensing type controls in the UK, although
they are used in some parts of continental Europe, particularly on
pedestrian footpaths.

[charles]

Post by Andrew Gabriel

Norway - At highway 155 in Nes i Hole, 220 radars have been installed
on light poles. They detect oncoming traffic and adjust the strength
of the light. By doing this, the 9 km/5.5 mi stretch saves a whopping
2100 kWh per week. The extra investment will break even after just 4.5
years.
http://youtu.be/mi8eE_NEfHM

In the UK they save even more money by simply not lighting the roads.

There has been a trend to switch off the lights on rural roads/motorways
outside busy periods. In some cases, they have been permanently switched
off. Also, many have been changed to delay switch-on until much lower light
level than used to be the case.
In UK, many of the new LED streetlamps which are controlled by mesh
networks have their light level set remotely, and automatically adjusted
at different times of night. They can be adjusted for once-off events
too, when a council is prepared to pay extra to have them on brighter for
longer if there's a local event resulting lots of people around later.
I am not aware of occupancy sensing type controls in the UK, although
they are used in some parts of continental Europe, particularly on
pedestrian footpaths.

The LED lights at our railway station and a footpath outside seem to sense
the presence of a person; they get brighter when you approach.

[Andy Burns]

Post by charles
The LED lights at our railway station and a footpath outside seem to sense
the presence of a person; they get brighter when you approach.

The LED lighting in Sainsbury's do that (quite subtly) you have to go
down an unpopular aisle when the shop is deserted to see it, also a
local multi-storey has fluoro tubes that gently dim up and down as you
walk past different sections.