Copied from my Night Owls Astronomy blog

http://garyshelley.blogspot.ca/

L.E.D Street Lights

     In an effort to be "green", reduce lighting and hydro costs many towns and cities are switching to modern L.E.D lights.  The L.E.D lights are brighter and consume less hydro than older arc lamps.  The Royal Astronomical Society of Canada has been a strong advocate for reducing light pollution and we encourage cities and towns to use more directional lighting fixtures.  Directing the light where it is needed without lighting up everything else including the sky is the main goal.  I have heard mixed reviews of the newer L.E.D lamps, so today when I saw the utility truck in my neighbourhood putting in the new lamps, I watched with a certain amount of anxiety.  Would the new lamps make things better or worse in my back yard, where I observe when not using the club's dark site?  As darkness set in tonight I waited.  The new lights were definitely bright (as shown in the picture), and certainly lit up the road area more than the old bulbs.  The old street lamps were high pressure sodium lamps which give off a yellowish light, and these new L.E.D lamps were more of a daylight 5-6000k white light.  The new lights may be brighter, but I am pleased to say the bulk of the light is concentrated on the roadway. There is definitely less back-lighting or scattered light from the new lamps.  Behind the house where I observe is actually darker with the stray light removed, in fact, even the front yard is darker.  Success!  So, in my case the cities switch to the new L.E.D lamps has been a change for the better.  My street is still nice and bright, and it's actually darker in the areas I observe from.  The city saves money, without negatively impacting my ability to observe, I like it!  I have heard some complaints from other astronomers about these new lights being too bright, but on my street brighter hasn't meant worse.  In my case, the streetlight is on my side of the road, and it seems to light up the neighbours yard more.  I suspect if this were not the case, and the light were across from us, shining in our direction I would not be so happy about the change.  As it is, it has worked out for the better.  I think good or bad is going to depend on location, location, location!