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Petitioners say Northampton LED streetlights too bright

Petitioners: LEDs in Northampton don’t reduce light pollution enough

  • LED lights in use at Cutter and Ziskind Houses at Smith College, Thursday. —JERREY ROBERTS

  • A URB2 warm white LED light, left, glows beside a URB1 white light, center, and a URB2 white light on Pleasant Street, Thursday. —JERREY ROBERTS

  • These streetlights on Pleasant Street show three of the four variations of the new LED lights that are being installed in different parts of the city. They city plans on replacing all municipally owned streetlights by the end of this summer, though some residents believe they don’t go far enough to reduce light pollution. JERREY ROBERTS

  • A URB1 warm white LED light, top, glows beside current amber-colored street lights on Pleasant Street, Thursday. —JERREY ROBERTS

  • A URB1 white light, left, glows beside a URB2 white light, center, and existing amber-colored lights, Thursday. —JERREY ROBERTS

  • LED lights in use at Cutter and Ziskind Houses at Smith College, Thursday. —JERREY ROBERTS

  • A RES1 warm white LED light, top, glows beside a current amber-colored light Thursday on Holyoke Street. —JERREY ROBERTS

  • The brighter white LED light, left, glows beside a current amber-colored light Thursday on Holyoke Street. JERREY ROBERTS

  • This map shows the locations of the different types of LED streetlights being tested in Northampton. Larry Parnass—CITY OF NORTHAMPTON



@cmlindahl
Saturday, May 21, 2016

NORTHAMPTON — As the city readies to replace over 2,000 streetlights with energy-efficient, LED fixtures, a citizen petition circulating argues that the new bulbs do not go far enough in reducing light pollution.

But city officials say the new bulbs are far better than the LEDs that have been installed by other communities and are a big improvement over the existing traditional lights currently in use by the city.

The city plans to replace all of the municipally owned streetlights with LED fixtures by the end of this summer in an effort to save over $170,000 in energy costs annually and reduce greenhouse gas emissions compared to the less efficient lights currently in use.

The project will cost $980,405, and will be offset by an expected $190,000 in energy efficiency rebates from National Grid. The lights are expected to pay for themselves within five years.

But residents will likely take most notice to the visual, rather than financial difference. The new fixtures will cast a light that is whiter than the yellow/amber rays of the city’s current streetlights.

Because of that color difference, the LED fixtures need to produce less light in order to produce the same level of visual clarity, according to Chris Mason, Northampton’s energy and sustainability officer.

But city resident James D. Lowenthal says that’s still more light than is needed.

“It’s great that Northampton is concerned about its energy use and carbon footprint,” Lowenthal, a professor of astronomy at Smith College, said Thursday. “However, not all LEDs are the same.”

Lowenthal said he began circulating the petition Wednesday and a day later had about 40 signatures. The group intends to collect more signtures this weekend and submit the petition to the mayor and City Council on Monday.

The warmth or coolness of light is measured on the Kelvin scale. The lower on the scale, the warmer the color of the light appears.

The city plans on using lights that are 3,000 K and 3,500 K. Lowenthal said the city should use lights of an even warmer temperature, 2,700 K or lower. And the fixtures should be “like an overturned bucket, with the light shining under.”

The sample lights that have been installed on Pleasant and Holyoke streets and Randolph Place are flat, without a shield.

Resident input

The city earlier this month collected residents’ input on those lights, which come in four different flavors – 3,000 K bulbs of one brightness set to be used in residential areas, 3,000 K bulbs of a higher brightness set to be used in urban areas and two different 3,500 K bulbs to be used at some intersections and crosswalks in residential and urban areas. 

Lowenthal said that all four of the lights continue the assumption that more light is better.

“We tend to want to push back the night,” he said. With LEDs, “now we can do it cheaply — turn the night into day.”

He said the new lights produce a significant amount of glare, causing the light to scatter and reflect off surrounding buildings and pavement.

Such glare contributes to light pollution, which can have health effects on people that stem from sleep disruption, affect animals and ruin the view of the night sky.

If the lights were shielded to limit light to only point downward, it would also save further energy costs, and would actually be safer for motorists by reducing the amount of light shining into their eyes, Lowenthal said. 

In fact, glare is the major factor whenever LED lights are installed and replace the typical cobrahead-style street lights, said Gary Hartwell, project manager at Smith College.

The college has replaced its conventional high-pressure sodium lights with LED lights, but made sure that this pedestrian lighting remained warm in color, accomplishing this through using frosted lenses and reducing from 100-watt bulbs to 13-watt bulbs, Hartwell said.

“LEDs can be a very high-glare light source, whereas cobrahead has a frosted lens over it, so the intensity of the emitting device is somewhat diminished,” Hartwell said. “LEDs typically don’t have frosted lenses; they are very directional and use a lot less electricity and have a longer life expectancy.”

In Amherst, LED streetlights were installed after the town received money through the state’s Green Community program. They have cut the annual cost of streetlights from $125,000 a year to $45,000 to $50,000 a year, said Department of Public Works Superintendent Guilford Mooring.

“The LED lights have saved us a lot of money on electricity,” Mooring said.

He said the town received some calls after installation about some of the lights, but most of those calls were resolved by adjusting fixtures. Some of the LED lights were shielded to prevent glare, Mooring said.

Glare debate

Mason said the new lights will actually reduce upward light scatter and likely produce less glare than the ones currently installed.

Lowenthal said the city should consider purchasing light fixtures that are shielded and reduce glare, such as those that have been installed at Smith College and in Burlington, Vermont.

And cities such as Sherbrooke, Québec, have had success in using even warmer, 1,800 K amber-colored LEDs. Those lights produce about seven times less light pollution than a 3,000 K light, Lowenthal said.

“It should all be the highest quality of light that we can get,” he said. “I think we’ll find that once we control the glare, we’ll be able to go to a much lower level of ambient light” without compromising pedestrian or motorist safety.

Mason said the lights at Smith College are placed closer together, reducing the level of contrast between dark and light areas and that the lighting plan being considered by city officials is based on what’s considered safe by engineers.

If Northampton were to install similar light fixtures, that would leave too much of the street in the dark, Mason said. To utilize those lights safely, there would need to be a major redesign of the city’s lighting system — something that would take time and which would threaten the grant funding being used for the project. Such changes would also be more expensive. 

Installing these lights is “a step in the right direction, one that we can afford right now,” Mason said.

And as for moving to a warmer LED light, Mason said it comes down to available money.

In order to be eligible for an energy-efficiency rebate from National Grid, the city can only install light fixtures that are listed on an inventory.

Until recently the warmest lamp was 4,000 K. Around the time that officials heard feedback from residents concerned that was too cool, the utility added a 3,500 K and 3,000 K models, Mason said.

“We have shifted to those as an option – but only because we had heard from some community members,” Mason said.

And Mason said officials would consider an even warmer light if that light was added to the list of those approved by National Grid. But it’s not something that can hold up the project, he said.

Public safety

Hartwell said the debate boils down to a conflict between the appropriate lighting for public safety and the cost to provide that service. But he acknowledges that will be a challenge to settle this debate when the illumination is coming from high off the ground.

"The higher you go the more difficult it is to reduce glare," Hartwell said.

Hartwell compares the problem to drivers who are on a dark road and have no problem seeing with the illumination from their headlights until a car approaches from the other direction, creating glare.

City Council President William H. Dwight, who also sits on the Energy and and Sustainability Commission, said the city cannot succumb to “decision paralysis.” Like those buying a smartphone, there are pros and cons to be weighed about buying now versus waiting to see what new features come out – or in this case, if the utility adds warmer bulbs to its list.

“I applaud his (Lowenthal’s) advocacy – it’s made a big difference on how we approach this,” Dwight said. “But at the same time, there’s a tipping point, a push-come-to-shove point.”

Dwight said it’s important to consider the restraints present on the project when assessing how the project should best move forward.

“Given the constraints and the rigor by which Chris has pursued this and coupled with Dr. Lowenthal’s citizen advocacy and what the circumstances are now, this is the best package that we can get given all the constraints,” Dwight said. “We don’t want to lose the opportunity for the funding, we don’t want to lose the opportunity for savings and reduction of (energy) consumption”

Staff Writer Scott Merzbach contributed to this report. Chris Lindahl can be reached at clindahl@gazettenet.com.