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[DSLF] Digest Number 1523
There are 15 messages in this issue.
Topics in this digest:
1. Re: Sky glow from greenhouses
From: Steve Davis <w2sgd@juno...>
2. lighting retrofits
From: Susan Harder <lookout@hamptons...>
3. Re: calculating steradians
From: "TriAstro" <triastro@oregontrail...>
4. Re: Sky Glow from greenhouses
From: Jim & Mary Ronback <Jim_Ronback@dccnet...>
5. purchasing fixtures
From: "Eric S. Johansson" <esj@harvee...>
6. Re: Re: Sky glow from greenhouses
From: Aaron Reid <sheilds76man@yahoo...>
7. Re: calculating steradians
From: "ctstarwchr" <ctstarwchr@aol...>
8. Re: purchasing fixtures
From: ctstarwchr@aol...
9. 041214 RE: calculating steradians
From: "Christopher J Baddiley" <cj.baddiley@physics...>
10. Lake Tahoe Study
From: Stephen Pauley <spauley@cox-internet...>
11. LAN and zooplankton
From: Stephen Pauley <spauley@cox-internet...>
12. Pocatello, Idaho
From: Mike Hansen <mhansen@einhornresearch...>
13. Re: purchasing fixtures
From: "Barry Johnson" <johnsonb52@comcast...>
14. RE: Sky glow from greenhouses
From: "Friedel PAS" <friedel.pas@bvpartners...>
15. RE: Re: Sky glow from greenhouses
From: "Friedel PAS" <friedel.pas@bvpartners...>
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Message: 1
Date: Tue, 14 Dec 2004 08:30:28 -0500
From: Steve Davis <w2sgd@juno...>
Subject: Re: Sky glow from greenhouses
Cliff wrote:
>All kidding aside, I am curious what types of plants they are growing
>because all green plants require a period of darkness to complete their
>process of photosynthesis properly.
Roses (in the US) for one. The idea is to *force* growth so they are
readily available for sale at any time of year. [Hint: If you suddenly
get a bunch from an unknown source, somebody may be ready to shoot
your lights out.]
Man has been messing with Nature in other ways as well.
Look at all the cultivated and hybridized plants and Dolly the
sheep. Is it any wonder that we have skyglow? Money rules! -sd
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Message: 2
Date: Tue, 14 Dec 2004 08:48:05 -0500
From: Susan Harder <lookout@hamptons...>
Subject: lighting retrofits
Last night I presented a poster entitled "Starry Starry Night", from a mural
painted by a class of second graders, with their four poems about the night sky
(and turning off unnecessary lights) at a School Board meeting. We are selling
it to raise funds for art supplies--100% of proceeds. It renders the Historic
District around the school with sky glow, that will now be changed through a
lighting policy, drafted by me, and passed last night by the School Board. The
School Board also told the power authority to take down five of six of their
utility pole floodlights (five were redundant lighting.) We also got the Town
to change out the sag lens cobra heads to flat lens on the street in front of
the school. They will be changing out their wall packs and PAR bulbs to
Glarebusters.
Susan Harder
Goal: help change 1 million light fixtures. (about 950,000 to go)
http://www.darkskysociety.org/
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Message: 3
Date: Tue, 14 Dec 2004 08:30:59 -0800
From: "TriAstro" <triastro@oregontrail...>
Subject: Re: calculating steradians
This whole discussion about steradians has certainly made my point about lighting
specifications, metrics, and standards not being understandable to the lay person. Sure,
as an engineer, I can understand the discussion, but who in the real world cares? I
worked in acoustical engineering for many years, and that field too was rampant with
technical terms, metrics and formulas that would baffle even the most dedicated
practitioners, let alone the lay public. I was sure that specialists in the field were
just inventing new metrics to get their name in the literature and perhaps get some type
of noise descriptor named after themselves. One fellow I worked with always said that if
you can't dazzle them with brilliance, baffle them with BS. Well, it appears to me that
the lighting 'game' is in the same boat. I would hope that this group would focus on
simplifying the types of metrics used to describe lighting issues. The issues we are
trying to deal with in light pollution are public awareness issues. All this other
engineering stuff is unnecessary for what DSA is all about, IMHO. The simpler the better.
Our people need to be able to explain this stuff to the public in terms they can
understand and yet are still technically sound and correct. Steradians and similars
terms, metrics and standards just are not going to get us there....
I'll now crawl back under my rock....
Tony George
Umatilla, Oregon
(541) 922-2517
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Message: 4
Date: Tue, 14 Dec 2004 08:36:25 -0800
From: Jim & Mary Ronback <Jim_Ronback@dccnet...>
Subject: Re: Sky Glow from greenhouses
They are growing tomatoes here in Tsawwassen, BC in soiless troughs.
They can accelerate growth 40x all year round using hight intensity
lights . They shutdown the lights for 4 hours from 8 to 12 pm. Since
their floors and benches are covered with a white plastic reflective
material to increase exposure on all sides of the plants, there is a
tremendous amount of light scattered and wasted through the clear glass
on the top. Because of the uproar caused in our community they plan to
extend the shutdown from 6 to 12 pm and maybe add some shading on the
sidewalls later. The real problem is that there are no provincial
standards for farms for lighting. The standards cover only noise and
dust. Municipal bylaws cannot be applied to greenhouse farms even though
they are within the municipality. As a result they have carte blanche. See:
http://www.delta-optimist.com/issues04/114204/news/114204nn2.html
http://www.delta-optimist.com/issues04/122104/news/122104nn6.html
http://www.southdeltaleader.com/portals-code/list.cgi?paper=48&cat=23&id=343576&more=
Is anyone familiar with moveable shading that could be used on the top
of the greenhouses?
Yours under beautiful dark skies,
Jim
> Date: Mon, 13 Dec 2004 21:51:04 EST
> From: ctstarwchr@aol...
> [-snip-]
>In your case try to first discover what kinds of plants this greenhouse
>is growing and inquire why they need to have their lighting on all night.
>Maybe they have a faulty electrical timer that is meant to maintains a
>certain circadian light/dark rhythm that has malfunctioned.
> [-snip-]
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Message: 5
Date: Tue, 14 Dec 2004 12:51:00 -0500
From: "Eric S. Johansson" <esj@harvee...>
Subject: purchasing fixtures
friend of mine who has a small organic farm in in a nearby town needs to
put lighting on his driveway/entrance. I went to the local hardware
store which had a couple of rather dusty 50 watt HPS full cut off
fixtures. But much to my surprise, they were gone.
Now I'm trying to figure out what the heck to do. where can one
purchase full cut off fixtures off-the-shelf? Well, I will call a
couple electrical supply and hardware stores in the town (which has a
light pollution control ordinance) and see if I can find anything.
baugh light bug
--- eric (westford ma)
--
its scary when Eastern Europe, formerly occupied by the Soviet Union
has a higher level of civilized living than the United States. (as
reported by a U.S. citizen emigrating to Estonia)
________________________________________________________________________
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Message: 6
Date: Tue, 14 Dec 2004 12:23:00 -0800 (PST)
From: Aaron Reid <sheilds76man@yahoo...>
Subject: Re: Re: Sky glow from greenhouses
Good point all. When I worked in the garden/nursery business, never do I recall all of the lights being on in the Greenhouses, or any of the hoops that were outfitted with electrical sources. It was used for circulation fans, as well as the heaters. During the winter months, like now, they only have there sign lit (down lit) one of the things that I made sure was complete before I took on a different job. So it is baffling to hear of a green house alight, especially the entire night.
Susan, great to here of the removal of 5/6 poles in the parking lot at that school. Our local school district here in GJ, Colorado is starting to get the idea themselves. Any new schools have to be built with full cutoff no matter what the source is. I'll be sure to watch them in any event.
Eric: I've tried my luck at our local Lowe's store. I don't know how close you are to big box stores. However on occasion they carry fixtures, that look decorative, and can function as full cutoff, so long as the bulb stays up and above the cutoff point. It's too bad, that all hardware stores don't have neighborly friendly lighting sections. One would think they could carry at least 2 or 3 decent fixtures, instead of all the glary stuff. I would be surprised if your Home Depot didn't have some solar and or low voltage equipped Malibu lighting. Most of all the stores I've been in have that sort of thing. It's low intensity, non-glarey/shielded, with obvious exceptions, and installation is a snap, I've found it @ Home Depot, Lowe's, Sutherland's, True-Value, and ACE.
Aaron, CO
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Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
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Message: 7
Date: Tue, 14 Dec 2004 19:30:32 -0000
From: "ctstarwchr" <ctstarwchr@aol...>
Subject: Re: calculating steradians
--- In DarkSky-list@yahoogroups..., "TriAstro" <triastro@o.....>
wrote:
> This whole discussion about steradians has certainly
> made my point about lighting specifications, metrics,
> and standards not being understandable to the lay person.
> Sure, as an engineer, I can understand the discussion, but
> who in the real world cares?
Tony:
You are indeed right that 99.9999% of the people standing in
the checkout line at the local grocery store would neither
understand nor care one iota about steradians, but people
who deal with applying low-impact outdoor lighting for a
living or pleasure need to know this stuff. To understand
it comprehensively, and to also assure reasonably good advice
is given to others, we really do need to study it in detail
before we can simplify it for the general masses.
Please do not think I'm hammering you because that is not
the intention. Light and the distribution thereof becomes
a very complex subject when dealing with topics like luminaire
design and refinement (many of us here do that for a living)
for fixtures to be as environmentally friendly as possible to
the outdoor nighttime environment. As a professional engineer
you must be familiar with the *mantra of enlightenment* known
as "Thinking outside of the box." ;-)
One thing I love about this Forum is fact that we have people
in here with a great diversity of specialties and skills who
collectively form a base of knowledge and wisdom that is very
difficult to match anywhere else. Some might think I pose pretty
off-the-wall questions occassionally (like this steradian thing),
but there is always a method to my madness for doing so.
The Disney people call it, "Imagineering."
> One fellow I worked with always said that if you can't
> dazzle them with brilliance, baffle them with BS.
He was a wise man! In literal terms that is the whole point I'm
shooting for Tony! I'm trying to discover the precise outdoor
fixture aiming (or shielding) point where the atmosphere is NOT
dazzled with ANY brilliance. ;-)
To determine that point where important thresholds occur,
especially with things like high intensity sports lighting
and floodlighting (and developing effective laws to control
and manage them without compromising the performance results)
we are first required to develop that comprehensive level of
understanding before any of us can give *effective* advice
that we can have the reasonable assurance *will* work.
Please pardon the pun, but I rue taking *shots in the dark*
where maximum vertical aiming angles are concerned. Sorry
for being so curious! :-/
Cliff Haas
Author Light Pollution Awareness Website (LiPAW)
http://members.aol.com/ctcadman
http://www.crlaction.org
Member: IESNA, CRL, NELPAG, AARP
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Message: 8
Date: Tue, 14 Dec 2004 14:47:25 EST
From: ctstarwchr@aol...
Subject: Re: purchasing fixtures
In a message dated 12/14/2004 1:21:37 PM Eastern Standard Time,
esj@harvee... writes:
> Now I'm trying to figure out what the heck to do. where can one
> purchase full cut off fixtures off-the-shelf? Well, I will call
> a couple electrical supply and hardware stores in the town (which
> has a light pollution control ordinance) and see if I can find anything.
Eric:
You might try the McMaster-Carr company and also Grainger Industrial
Supply Corporation. Grainger offers a Type II flat lens cobra for
$152 but it is not full cutoff (it's a cutoff according to photometry).
Enter "outdoor lighting" as the search string at either location.
http://www.mcmaster.com/
http://www.grainger.com/Grainger/wwg/start.shtml
Another source you may try is Lowes. Some stores stock the
fully shielded barn bomb (I think made by Regent Lighting?) on
their shelves.
Also, nearly every manufacturer has listings for local representatives
on their web sites, but I doubt if you will find much in the form of
full cutoff fixtures on the shelves in a local hardware store. For
around $750 you can get a nice full cutoff HPS shoebox and a 25' high
pole.
Clear skies and good seeing,
Keep looking up!
Cliff Haas
Author Light Pollution Awareness Website (LiPAW)
http://members.aol.com/ctcadman
http://www.crlaction.org
Member: IESNA, CRL, NELPAG, AARP
[Non-text portions of this message have been removed]
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Message: 9
Date: Tue, 14 Dec 2004 20:17:28 -0000
From: "Christopher J Baddiley" <cj.baddiley@physics...>
Subject: 041214 RE: calculating steradians
Unfortunately I had difficulty following what you were doing with your
AutoCAD. So I wrote my own observation as a physicist working in thermal
radiometry in the hope this will help.
By the way, I have no interest in defining new obscure standards ! I like
to keep things very basic. I always work from first principles.
Keeping things simple...
A radian is a linear angle, it has no shape, just an angle, 1/(2 pi) of a
circle. It is the angle subtended at the centre of a circle by its radius
marked out as circumferential arc of the circle.
A steradian has no specified shape. It is just a solid angle subtended by an
area (any boundary shape) over the surface of a sphere that has the same
curved surface area numerically as the sphere radius squared, and is 1/(4
pi) of a sphere.
Now for radiometry.....
I have always considered photometric units such as luminance or its
equivalent unit radiance Watts/m^2/steradian, or for that matter illuminance
lux, or irradiance W/m^2…as incremental.
By that I mean limiting value as area (and solid angle for the former cases)
diminishes to zero.
For example, to say a surface emits so many W/m^2 or lux, does not mean it
must have a 1 metre square area. It could be anything. This is its limiting
incremental value.
Similarly to say a surface at black body temperature and emissivity of such
and such radiates so many W/m^2/steradian/ micron bandwidth (its radiance),
is its incremental value. Indeed knowing the radiance at a wavelength or
over a waveband or all wavebands, and given the emissivity. gives the
temperature.... a scalar physical property of the surface, not dependent in
its size or shape in definition.
By my interpretation then, when a luminaire’s luminance, or as I prefer
radiance in a particular direction is E W/m^2/sr etc, the solid angle is
not a steradian. It is a limiting incremental value in that direction, not
measured over a whole steradian. It could have been measured over a micro
radian as E x10^-12 Watts, from a radiating area of 1 mm square, the ratio
gives the same number.
So the actual shape of the boundary of the area or the solid angle is not
specified and not relevant. For large distances you can think the projected
area of the solid angle as flat. It could be a flat square as this is easy
to imagine and compute.
Here is a real example to clarify or confuse…
To find the total radiant emission from a flat surface from the incremental
Planck radiance function (W/m^2/sr/um waveband). The Planck function is
incremental too, and is just a scaling so left out here.
Described in words…. Consider area as seen form an angle away from the
normal , hence we have a cosine angle term. Let it be seen at all angles in
a hemispherical arc at this angle to the normal. On unit sphere, you get a
sine of the angle for the arc radius times an increment angle times pi for
the circumferential arc length. Add over all angles without repetition.
The answer may seem weird, but is logical. The integrated value over the
hemisphere seen by the flat surface in half that, i.e. not 2pi steradians
(hemisphere) but pi steradians. It was the projected area that halved it.
This is Lambertian surface emission. By the way, the reflectivity is 1-
emissivity. Then reflectivity varies as 1- cos the angle (increasing away
form the normal). This is quite close to the Fresnel equations result
ignoring polarisation.
The radiation is preferentially beamed in the direction of the normal. It
has twice the mean value as seen on axis, to zero along the surface.
When I do integrated sphere calculations and upward light ratios for
manufacturer's luminaires, and reflectivity component sums etc, my program
checks that.... for equal unity luminance in all directions, the total of
all incremental angles is 4 pi (about 12.57)
I do not know what the ‘adopted definitions’ say for foot candles etc., but
I think in terms of physics. I will leave it at that. In my book if it says
for 1 steradian, don’t take it literally !
I will now crawl back under my stone (as a frustrated astronomer) and
promise not to confound you with irrelevant twaddle again (for a while).
Sorry !
Chris
-----Original Message-----
From: ctstarwchr@aol... [mailto:ctstarwchr@aol...]
Sent: 14 December 2004 10:22
To: DarkSky-list@yahoogroups...
Subject: Re: [DSLF] calculating steradians
etc.....
In a message dated 12/13/2004 7:11:45 PM Eastern Standard Time,
cj.baddiley@physics... writes:
> I do not know what is in any handbook but the steradian is
> simplicity itself..
Thanks Chris & David,
I agree on the conceptual simplicity after banging my head on the
wall many times over the years trying to absorb and understand
how a steradian would actually look in space. Due to the constraint
of the curved subtended area of a sphere, the steradian (in this frame
of reference) could only be the shape of a cone because that is the
only geometrical shape where all points along its base evenly contact
the subtended surface of a sphere, thus forming that circle shape on
the sphere's surface confirmed by David's previous message.
etc....
Clear skies and good seeing,
Keep looking up!
Cliff Haas
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Message: 10
Date: Tue, 14 Dec 2004 14:31:57 -0700
From: Stephen Pauley <spauley@cox-internet...>
Subject: Lake Tahoe Study
>>Mike Hansen <mhansen@einhornresearch...>
Subject: Lake Tahoe Study
Mike wrote >>Based on concerns expressed by an IDA member, the Tahoe Regional
Planning Agency is going to look into the impact of lighting from piers
around the lake on the aquatic environment. A news report is available
at:
http://www.rgj.com/news/stories/html/2004/12/10/87331.php?sps=rgj.com&sch=LocalNews&sp1=rgj&sp2=News&sp3=Local+News&sp5=RGJ.com&sp6=news&sp7=local_news&jsmultitag=news.rgj.com/news/local
>>
================================
Mike
The following scientists have published on how LAN
affects zooplankton. In fact some of Marriane Moore's research was done
at Lake Tahoe, the area in question.
Gliwicz ZM 1986 1999
Dodson S 1990
Moore MV et al 2000
For Marianne Moore's publications go here:
http://www.wellesley.edu/Biology/Faculty/Mmoore/Content/Moore_CV_04.doc
According to the Tahoe article, an attorney, using his "intuition",
told the folks at Tahoe not to worry.
"Gregg Lien, an attorney representing Tahoe shoreline property
owners who want the ban on pier construction lifted, said he
doubts the lighting issue is significant.
"When the day is done, I don't think this is going to be a serious issue,"
Lien said. "My intuition says there probably isn't much of an impact."
God help us.
Steve P
--------------------------------------------
[Non-text portions of this message have been removed]
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Message: 11
Date: Tue, 14 Dec 2004 15:07:27 -0700
From: Stephen Pauley <spauley@cox-internet...>
Subject: LAN and zooplankton
More on Moore's work:
http://www.wellesley.edu/Biology/Faculty/Mmoore/research_experiments.html
"Because Daphnia and Bosmina responded in a more normal fashion within the
black enclosures – which simulated a dark night – we concluded that ANL
reduces both the amplitude and magnitude of the zooplankton movements near
the surface. As a result, we speculate that increased amounts of surface
algae may be left unconsumed by the zooplankton and potentially lead to
algal blooms and a change in water quality. But, this has yet to be
confirmed. "
Steve P
[Non-text portions of this message have been removed]
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Message: 12
Date: Tue, 14 Dec 2004 17:56:07 -0500
From: Mike Hansen <mhansen@einhornresearch...>
Subject: Pocatello, Idaho
According to the mayor of Pocatello, Idaho which has shut off many
street lights over the past couple of years to save money (over
$100,000), there hasn't been any measurable change in the number of
traffic accidents. And, "The traffic folks don't think its a safety
issue."
Read more in an article at:
http://www.journalnet.com/articles/2004/12/14/news/local/news01.txt
Mike Hansen
2561 Massachusetts Ave. #1
Cambridge, MA 02140-1020
(617)661-6520
[Non-text portions of this message have been removed]
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Message: 13
Date: Tue, 14 Dec 2004 20:08:01 -0500
From: "Barry Johnson" <johnsonb52@comcast...>
Subject: Re: purchasing fixtures
This is not "off the shelf", but you might try the AC Series (Area Cutoff)
from Ruud Lighting. Available with 35-50-70 W HPS and 50-70-100 W metal
halide. There is a yoke mounting option available for the AC Series which
permits mounting on wooden utility poles, but you didn't mention whether
your friend anticipates pole mounting or wall mounting.
Ruud Lighting sells factory direct to electrical and landscape contractors
and installers, and electrical wholesalers. Virtually anyone the electrical
business can order directly from Ruud. An electrical distributor should be
able to get these within a few days.
You can also get a NEMA head "barnyard style" fixture from Hubbell Lighting
(about $90 with 100 W HPS) and equip it with the Hubbell Sky Cap (about
$30). Hubbell catalog number NPU-10S1-BI includes both.
There is also the GE Skygard series.
Barry Johnson
.
----- Original Message -----
From: "Eric S. Johansson" <esj@harvee...>
To: <DarkSky-list@yahoogroups...>
Sent: Tuesday, December 14, 2004 12:51 PM
Subject: [DSLF] purchasing fixtures
>
>
> friend of mine who has a small organic farm in in a nearby town needs to
> put lighting on his driveway/entrance. I went to the local hardware
> store which had a couple of rather dusty 50 watt HPS full cut off
> fixtures. But much to my surprise, they were gone.
>
> Now I'm trying to figure out what the heck to do. where can one
> purchase full cut off fixtures off-the-shelf? Well, I will call a
> couple electrical supply and hardware stores in the town (which has a
> light pollution control ordinance) and see if I can find anything.
>
> baugh light bug
>
> --- eric (westford ma)
>
> --
> its scary when Eastern Europe, formerly occupied by the Soviet Union
> has a higher level of civilized living than the United States. (as
> reported by a U.S. citizen emigrating to Estonia)
>
>
>
>
>
> _________________________________________________
> To subscribe to the DarkSky List Forum send email to:
> DarkSky-list-subscribe@yahoogroups... or visit:
>
> http://groups.yahoo.com/group/DarkSky-list/join
>
> Help save your town from obtrusive lighting --
> Invite your Planning and Zoning department and
> local officials to join us! Please visit the IDA & CRL
> websites at http://www.darksky.org and
> http://www.crlaction.org frequently, too!
> Yahoo! Groups Links
>
>
>
>
>
>
>
>
________________________________________________________________________
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Message: 14
Date: Wed, 15 Dec 2004 00:35:02 +0100
From: "Friedel PAS" <friedel.pas@bvpartners...>
Subject: RE: Sky glow from greenhouses
There exists screens that can computer driven get the light insite the
greenhouse.
The work fine for greenhouses for flowers. They help also to reduce the cost
for energy with 15 tot 40 % (heating cost). In Flanders the government pay
also 40% of the installation cost back.
The problem is the green houses for vegetables. There the climatology in the
greenhouses is a lot more complex. We are looking out for sollution for
that, but need money for those studies. In the Netherlands indeed the
problem is big and also looking for a study currently that must ging
solutions.
Another reason that one farmer (flowers) gives me that he installed that was
against thieves. Thieves were using the lights for canabis plantages.
Installing the screens resulting in less thieves for the lights...
No time now to go deeper on this topic because of my wedding this weekend
and honemoon travel after it, but in more than a month I want do that
well...
So remember me to it after mid of jaruary.
Regards,
Friedel
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Orion mail: Friedel.Pas@jvsorion...
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http://www.bvpartners.be
Boterlaarbaan 323
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Tel.: +32-3-320.83.74
Fax.: +32-3-320.83.79
GSM: +32-474-50.17.95
-----Original Message-----
From: jim_ronback [mailto:Jim_Ronback@dccnet...]
Sent: maandag 13 december 2004 18:28
To: DarkSky-list@yahoogroups...
Subject: [DSLF] Sky glow from greenhouses
Has anyone had success in reducing skyglow from greenhouses?
________________________________________________________________________
________________________________________________________________________
Message: 15
Date: Wed, 15 Dec 2004 01:23:17 +0100
From: "Friedel PAS" <friedel.pas@bvpartners...>
Subject: RE: Re: Sky glow from greenhouses
In green houses it is in a lot of cases full-cut off but the tighting is
verry itensive and so there is still a lot of sky glow as the result of
reflected lighting
We did in the past some calculations of how much km highway lighting of
flanders there was in only a small number of comparable number of football
planes spaces... I don't know the numbers now from my heart and currently
not the time to look them up!
Regards,
Friedel
---------------------------------------------------------------------
e-mail: Friedel.Pas@BVPartners...
Orion mail: Friedel.Pas@jvsorion...
---------------------------------------------------------------------
BV&Partners (Informatici)
http://www.bvpartners.be
Boterlaarbaan 323
2100 Deurne
Tel.: +32-3-320.83.74
Fax.: +32-3-320.83.79
GSM: +32-474-50.17.95
-----Original Message-----
From: Aaron Reid [mailto:sheilds76man@yahoo...]
Sent: dinsdag 14 december 2004 21:23
To: DarkSky-list@yahoogroups...
Subject: Re: [DSLF] Re: Sky glow from greenhouses
Good point all. When I worked in the garden/nursery business, never do I
recall all of the lights being on in the Greenhouses, or any of the hoops
that were outfitted with electrical sources. It was used for circulation
fans, as well as the heaters. During the winter months, like now, they only
have there sign lit (down lit) one of the things that I made sure was
complete before I took on a different job. So it is baffling to hear of a
green house alight, especially the entire night.
Susan, great to here of the removal of 5/6 poles in the parking lot at that
school. Our local school district here in GJ, Colorado is starting to get
the idea themselves. Any new schools have to be built with full cutoff no
matter what the source is. I'll be sure to watch them in any event.
Eric: I've tried my luck at our local Lowe's store. I don't know how close
you are to big box stores. However on occasion they carry fixtures, that
look decorative, and can function as full cutoff, so long as the bulb stays
up and above the cutoff point. It's too bad, that all hardware stores don't
have neighborly friendly lighting sections. One would think they could carry
at least 2 or 3 decent fixtures, instead of all the glary stuff. I would be
surprised if your Home Depot didn't have some solar and or low voltage
equipped Malibu lighting. Most of all the stores I've been in have that sort
of thing. It's low intensity, non-glarey/shielded, with obvious exceptions,
and installation is a snap, I've found it @ Home Depot, Lowe's,
Sutherland's, True-Value, and ACE.
Aaron, CO
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