Night Lights, Mercury Vapor VS HPS

[Doc_Bob]

Light the night is not a universal good thing and needs analysis. It is frequently better to be out of sight and out of mind except for nice bright motion detector lights.

Pat, my philosophy exactly. Wax on, ax off, light on, light off.It saves me lots and lots of money!!!!!!!!!!!!!!! Electricity ain't cheap.
Bob

 

[gizmo]

Actually, HPS gives considerably more most lumens per watt, especially as the bulb ages. This is why all city street lights are HPS. For example, a 150 watt MH light produces 13,000 initial lumens and only 8,700 mean lumens while a 150 watt HPS light produces 16,000 initial lumens and 14,400 mean lumens while a 175 watt mercury vapor produces only 7,850 initial lumens and 7,140 mean lumens.

And here I thought I was a Know-It-All. Thanks for the correction. I learn something new here every day.

 

[patrick_g]

BobbinIL, Do you have electricity planned for your shed or will the "porch light" make the requirement? There are solar powered IR motion activated porch lights available that you might like if you otherwise wouldn't be running electricity except for the porch light.

Pat

 

[Dargo]

Actually, HPS gives considerably more most lumens per watt, especially as the bulb ages. This is why all city street lights are HPS.

Well, that is also what I was told several years ago by a 30 year employee of our utility company. I didn't ask the specifics and certainly did not know the details you provided, but I really have not noticed much of cost to have 3 of them on every night. What amazes me is how long they last. One bulb is original from when it was installed about 8 or 9 years ago. I was, um, given a few spares by my buddy who works for the utility company but have only used 2, and that was after a minimum of 6 years.

 

[patrick_g]

Dargo, In one of my first engineering jobs I was the energy conservation officer of SUBASE San Diego and I met a lot of employees of the utilities. If there is a conflict between my understanding of physics and electronics and the opinion of a utility employee, irrespective of their tenure, I tend to discount opinion. Sometimes folks are well intentioned but misinformed or their knowlege base is obsolete.

Years of experience do not neccessarily imply professional growth or staying abreast of new developments. I was originally trained to believe that turning fluorescent lights on and off was more expensive than letting them run for extended periods. Well, since the energy crisis (remember the lines at the gas station?) the reality of that has changed through new fixtures with different ballasts and different tubes. Now if you are going to exit a space for more than just a couple minutes or so you are ahead overall to turn the lights off. This is just a single example but there are many. You can't believe the resistance I found to changing peoples minds about their preconceived notions,

Pat

 

[Dargo]

If there is a conflict between my understanding of physics and electronics and the opinion of a utility employee, irrespective of their tenure, I tend to discount opinion. Sometimes folks are well intentioned but misinformed or their knowlege base is obsolete.

Oh, I know nothing in this field. If there is something that is going to pay off in a relatively short period, I'm game to switch. I have no input or advice. I'm just a sheep in this field trying to find who to follow. I run 3 dusk to dawn lights at my place. Contrary to popular belief, "night vision" security cameras have a rather short range. Having the dusk to dawn lignts eliminates the need for the useless LEDs that are good for 10 feet when I need 100 feet. I've found I have much better security playback by using high quality low lux 1/3" cameras with the dusk to dawn lights. What lights would you recommend to be the most cost effective?

 

[ultrarunner]

Just a quick observation

Turning T8 fluorescents frequently on and off does dramatically shorten life.

I have T8 tubes with electronic ballasts in Hospital Corridors that are required to be on when ever the building is open, which is always. Many of the T8's are original and have been in place and on since December 1995.

I also have the same bulbs in storage closets and staff bathrooms where they need to be replaced about every 3 to 4 months due to frequent on-off cycles.

For cold temperature applications you need to order a ballast for cold temps. Gainger lists Ballasts for T12 lamps with a starting temp of -20 F

 

[patrick_g]

ultrarunner, I'm sure you have accurately reported your observations with those tubes and ballasts.

I would be willing to bet a rootbeer float that although the lamps in the hall that are over 10 years old and have been in continuous operation and not failed are in fact not economical to operate. I strongly suspect that their lumen output is so reduced by age that they are no longer giving you much bang for your buck.

This is a classic situation where tubes are not replaced unless they fail, even when they are no longer economical to operate. I would have thought that you would have a particular foot candle requirement to meet. If there is one and you are still meeting it then you were seriously over lamped 10-12 years ago and wasting electricity. There are adjustable output ballasts that allow you to "turn the fixture down" when equipped with new tubes and then over time you turn the ballast up to compensate for lamp aging.

Pat

 

[patrick_g]

Dargo, Are you using motion detecting software to look for motion on the camera video? If not, then what do the cameras take pix of when there is nothing moving? Where I am going with this is that you could use motion detecting lights (to save $ on electricity) and only video when the lights come on without missing anything of interest.

Pat

 

[Dargo]

The lights work as a great deterrent. I have two dual quad processors running 16 outdoor cameras covering my property and all entrances to all my buildings. They are on 24/7 recording to a DVR that runs on a 10 day real time loop. If I haven't noticed that something happened in 10 days I suppose it's shame on me.