Renewable energy committee explores Dark Sky program

Dimming outdoor lighting saves energy, cuts light pollution

By Lorraine Kreahling

Suffolk (County, NY) Times 2/08

There's water pollution, and air pollution, and soil pollution. And
now, another on that list -- if you haven't yet heard -- is light pollution.

Like all kinds of pollution, there's more than one reason to try to stop it.
That was the message Long Island Dark Sky Society's Susan Harder brought to a well-attended seminar at Town Hall sponsored by the Southold Town Renewal Energy Committee.

When we light up parts of the night environment where no light is
needed, we waste energy. Overlighting and glare also cause accidents -- and interfere with the pleasures of stargazing. And artificial light at night can be bad for plants, nocturnal animals, migrating birds and people.

Ms. Harder is so passionate about lights that you suspect she has
trouble sleeping at night. In fact, that's exactly what got her started.

More than 10 years ago, a church near her home installed outdoor lights that suddenly flooded her bedroom with artificial daylight. That's when she began asking questions about outdoor lighting -- and she hasn't stopped.

With other Dark Sky advocates, she is eager to point out that 30
percent of unshielded outdoor light goes up toward the heavens and to other places where it is not needed. All lights cost money to burn, and the annual price tag for unnecessary, wasted light in the U.S. is estimated at $4.5 billion.

Sitting through her hour-long seminar will change your night vision,
so to speak. You may find yourself wondering why a neighbor lights up the front of his house with unshielded PAR floodlights. (Isn't Christmas over?)

And what about those landscape lights left on all night long? Who is in the garden at 3 a.m.? You may realize that the streetlight that's been shining in your bedroom window for as long as you can remember is a cobra-head with the kind of drop lens that elsewhere on Long Island is getting retrofitted with a more sensible flat lens. Then you may remember that time you went to the dock to watch a meteor shower, but you couldn't see it because of the unshielded floodlight on the telephone pole.

"People equate lots of light with safety," Ms. Harder said. "But, in
fact, if a light is shining in your eyes you can't really see what's right
in front of you or where you are."

When confronted with bright unshielded light, like a bare bulb, the
eye's iris has trouble closing quickly and we temporarily cannot see. When that's reversed, when you look away from bright lights and back into the dark -- such as when you leave an overly lit service station -- you can't see because your iris takes time to adjust again.

Ms. Harder said glare from a bare floodlight on a house in dark woods
near her home may have been why a motorist struck and killed a pedestrian.

"The driver said he did not see his victim, and I believe him," she said.

What's to be done? Fixtures can be replaced, and a list of fixtures
approved by Dark Sky Society can be found at www.darksky.org.

Sometimes lights can simply be repositioned so their beams are trained downward rather than against walls and so they do not cross property lines. We can also add shields and other opaque protectors to outdoor lights. Additionally, those pretty period fixtures we're all familiar with as porch lights can be retrotfitted so that the bare bulbs are recessed and no longer create glare.

Finally, Ms. Harder said, we have to look, well, harder, at our habit
of leaving lights burning all night long. "For every 100-watt bulb that's
kept on from dawn to dusk for one year, a quarter-ton of coal must be
burned," she said. "If you're concerned about security and safety, you're
better off buying inexpensive motion sensors or timers."

She offered research suggesting lights do not deter crime. Several
schools found that keeping campuses and schoolyards dark not only saved tens of thousands of dollars in utility bills, but decreased graffiti as well.

She added that thieves have trouble doing what they want to do in the
dark. "Your neighbors are more likely to notice a flashlight moving inside a dark house than they will notice activity in a house that's fully lit all
night long," Ms. Harder said.

There are other reasons to make our nights dark again. Growing things
have light and dark cycles, and human beings are no different. The
neurohormone melatonin that helps our brains get to sleep is produced only in darkness, and there is evidence linking its absence to certain cancers.

Vegetation is also affected by artificial light. Shade trees in areas
with all-night lighting lose their foliage later in the season. Their
delayed dormancy can cause die-back from hard-freeze.

Songbirds also are victims of our light obsession. Birds use the stars
to navigate, and millions die each year after being thrown off their
migratory patterns by city lights. And some researchers think the crow and pigeon population explosion is due in part to all-night lighting, which
keeps nocturnal predators like the owl away.

Then there's the connection between lit waterfronts and algae blooms.
Zooplankton, which feeds on algae, is cued to rise to the surface by
darkness. So dawn-to-dusk light on water may keep it from coming up for its algae dinner.

Following Ms. Harder's presentation, Supervisor Scott Russell said
most people did not realize that more light in all directions didn't mean
safer streets, and that Southold would work to raise public awareness.

"People may think they want a lot of lights in public place," he said,
"but they also need to realize that it's their tax dollars that must pay for
every one of these lights. If you're wasting light, you're wasting money."

Southold's annual LIPA bill for streetlights alone is $250,000.

Mr. Russell said he hoped to lead Southold Town to a
dark-sky-sensitive light plan that would focus first on new commercial
construction. A public education program will also be part of the effort.

"People need to understand that light trespass is a property rights issue.
Light that is not yours does not belong on your property," the supervisor
said.

"This isn't only about saving the environment," he added. "It's about
saving money and energy -- and everyone wants to do that."

Friday February 22, 2008