Posted by Resident, a resident of Another Palo Alto neighborhood, on Nov 23, 2010 at 8:17 am
Residential areas are poorly lit. The street lights do a very poor job of lighting due to low lighting, too much distance between street lights and so many of the lights being surrounded by tree branches.
We have crews cutting trees around power lines, but I never hear about crews cutting trees around street lights to improve lighting. This must be the cheapest solution to improving residential lighting.
The City currently has 6,300 HPS streetlights. Assuming the pilot project finds continuing energy savings and subject to Council approval of the funding source, the Utilities Department will schedule replacements of all other HPS street lights in coming years. Replacing these HPS streetlights with more energy efficient ones can potentially reduce around 600 metric tons of greenhouse gases (GHG) per year upon full rollout by about 2015, which is equivalent to taking 120 passenger vehicles off the road annually. GHG reduction associated with upgrading the streetlights will help the City meet its GHG reduction target by 2020.
Unfortunately, there doesn't seem to be a systems analysis of the cost savings for operating LED street lights on a 10-year basis. The current bulbs have a nominal lifetime of about 5 years, but cost significantly less than the current cost of LEDs. The LEDs use significantly less power, so the installation costs, the power savings, and the fact that the lifetime of the LEDs should be much longer than the current bulbs should make this a "win". But .. there doesn't seem to be anything that backs up this supposition on the City's WEB-site.
It's a shame no one on the City Council seems to have any sense of what constitutes good documentation--and demand it from the City Manager. Making decisions about street lighting should be based on more than taking hypothetical cars off the street.
Posted by stargazer, a member of the Duveneck School community, on Nov 23, 2010 at 11:53 am
Why is there no commentary about these new lights and light pollution? Astronomers (Lick Observatory, for instance) made a big push decades ago to get streetlights that wouldn't destroy the ability to see the night sky... how do these new white, intense lights measure up when it comes to light pollution? Are we just re-creating a problem we addressed some years back?
Posted by Judith, a resident of the Leland Manor/Garland Drive neighborhood, on Nov 23, 2010 at 11:57 am
They're not $600 a BULB, they're $600 a HEAD. That's the whole object at the end of the pole, including the housing, mounting, lenses, etc. An LED bulb is a little tiny thing - each head has many, as well as reflectors to aim them correctly. Because they can be aimed, we should see somewhat better light distribution as a side benefit.
Posted by Charlie, a resident of the Midtown neighborhood, on Nov 23, 2010 at 12:54 pm
Someone mentioned doing cost analyses of LED vs. traditional sodium vapor street lighting. Of course analyses of been done, probably more by LED-street-light manufacturers as a sales tool. Part of the calculations include the expected lifespan of the LEDs. The companies may or may not provide realistic LED lifespan figures. What worries me is looking at many of the LED stoplights currently used in many local intersections. You'll see that many of the LEDs in the clusters of them in the stoplights have stopped working! I don't think the cities which purchased them expected them to die so soon .... Let the buyer beware of things that oftentimes seem to be too good to be true.
Posted by Let there be light, a resident of the College Terrace neighborhood, on Nov 23, 2010 at 1:34 pm
"how do these new white, intense lights measure up when it comes to light pollution?"
They are much better as the light is very directional and always pointed down. This property of LED lights is actually a problem with regards to residential lighting as most home fixtures are designed for incandescent bulbs which emit light in all directions.
Posted by Mo, a resident of the Barron Park neighborhood, on Nov 23, 2010 at 1:36 pm
> Of course analyses of been done, probably more by
> LED-street-light manufacturers as a sales too
Yes, that's probably true. The point of the comment is that this sort of analysis should have been applied to Palo Alto's streetlight grid to see what the likely cost/benefit analysis might be.
> many of the LEDs in the clusters of them in the stoplights
> have stopped working!
This may, or may not, be a problem. Any suggestion about the decrease in visibility of the light at various distances? Unless there is significant light loss (due to the LED elements that have burned out), this is probably not a problem. Of course, if the City finds itself replacing these bulbs frequently, then it is a problem.
Posted by Lycos, a resident of another community, on Nov 23, 2010 at 11:08 pm
Palo Alto always seems to be good in spending money on feel good projects so, by golly, LED street light will be replaced, whatever the "economic analysis" will say! Remember the "state of the art" "must have" photovoltaic panels at the Municipal Service Center? Remember the $60M library bond when SJ built a beautiful library for 1/4 of that? And the fiber to the home is not dead yet either ...
But we don't have money to fill the potholes. We don't have money to bury the electrical cables in the ground. We don't have money to ...
Posted by Emily, a resident of the Ventura neighborhood, on Sep 11, 2012 at 9:53 pm
Oh my! I have 4 new LED lights around my house. I feel like I am living in the middle of a used car lot. I can practically read in my bedroom at night. There is a horrible green glow from shrubs around the house. I hate them. I feel like moving.