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Red Harvest
10-02-2005, 20:47
Probably quite a few of you are already doing this, but I thought I would pass it on for others to consider. If you want to save substantial money over time, swap out your standard incandescent bulbs for some of the spiral compact flourescents. The initial price of the bulbs is high, but if you check around periodically you can find them at reasonable prices at SAM's, Home Depot, etc. They usually have 5 year warranties and they last many times longer than standard bulbs, so you come out OK on bulb costs. I swapped my high use bulbs out 9 months ago. One 3 pack of the bulbs failed within a few days...some sort of electronics defect since they all came from the same pack so I took those back for swap out. No failures since then with the ~20 bulbs I now have in service.

The big savings is in electricity use. The standard incandescent bulb wastes most of its electricity in the form of heat emissions rather than light. A 26 W spiral compact fluorescent emits about as much light as a 100 W standard bulb, while a 13 W spiral emits about as much as a 60 W standard bulb. Current electric prices around here are near 12 cents per KWH. Over the calculated life of the bulb a 26 W (100 W equivalent) spiral will save $71 -- per bulb. A 13 W will save about $45 -- per bulb. With the mix of ~20 bulbs I now have in service I expect to save nearly $1,200 over their lifetimes, assuming electricity prices don't double again (as they have over the past few years.)

There is a secondary benefit: reductions in air conditioning cost (and improvement in temperature uniformity in some rooms.) It is more difficult to quantify this and dependent on many factors. Based on some coefficients of performance for air con units in real world service I'm coming up with about half as much electrical savings as from the lighting savings--but only during air conditioning periods (summer months.) So where I live this would work out to be about 1/4 of the lighting cost reduction. It would be less farther north.

On that secondary benefit, the cooling effect/comfort level in a PC room is substantial. A modern PC and 19, 21 or 22" monitor put out a lot of heat on their own, probably 300+ W's during normal use, more at peak loads. As we all know, the room can get pretty toasty compared to the rest of the house, especially if one has multiple PC's. However, I also like plenty of light in my study since I do a lot of reading, calculating and researching, so swapping out the standard bulbs for the spiral fluorescents makes a big difference in the comfort level of the room.

A third benefit that I nearly forgot: I've been able to use higher luminescence but lower wattage bulbs in some enclosures. For example some lighting fixtures are limited to 40 or 60 W bulbs, because anything greater will overheat the fixture and risk a fire. With the spiral compact fluorescents I can put a 26 W (100 W equivalent) bulb in there, without the overheating problem. That isn't something I've seen on the package...so take this bit of info at your own risk. I'm not an *electrical* engineer, nor an electrician. Considering the total wattage is less, I believe this is still a conservative move (safety wise), but there could be an unintended consequence of which I am presently unaware.

Negatives? They don't work in dimmer mode, since they are either off or on. The hue of the light is slightly different and seems to be slightly dimmer than the "equivalent" 100 or 60 W bulb. Neither have been bothersome to me. (It isn't that "institutional" cold blue light effect.) The less rounded shape of the larger 100 W equivalent bulbs makes them a bit tighter fit in some fixtures.

UNRELATED Recommendation: Cut back on outdoor lighting. 90% of it is simply a waste. Dusk to dawn lighting is my arch nemesis as an amateur astronomer, as much of it simply projects unwanted light into the night sky. When flocks of birds fly over the city at night they look like someone painted their bellies in day glow colors--really odd. If you want security lighting, consider motion detector triggered lights, so that they turn on when you really want them on. Also, buy full cut off fixtures: ones that don't send light *upward* or parallel to the ground. Light sent out sideways only dazzles the eyes, and hampers the ability of people to actually see. (I enjoy demonstrating this at times by showing how a mock mugger/thief can work the resultant harsh shadows better than with no lighting at all. They see you, but you can't see them if they know what they are doing. Stealth can be fun...:batman: )

Proletariat
10-02-2005, 21:17
Interesting tip. Will check it out next time I'm replacing bulbs.

OlafTheBrave
10-02-2005, 22:48
I will back this one up as it is something I did a few years back. I didn't do it so much for the energy savings but I simply got tired of buying lightbulbs all the time. For some reason at my previous residence incandescents would just not last long at all. I think so far I have had two bulbs out of six that were about six years old burn out. Which is great considering my normal bulbs were lasting about 2 monts or so.

Crazed Rabbit
10-02-2005, 22:55
Thanks for the recommendations.


Cut back on outdoor lighting. 90% of it is simply a waste. Dusk to dawn lighting is my arch nemesis as an amateur astronomer, as much of it simply projects unwanted light into the night sky.

The man speaks truth! Nothing is more irksome than the huge amount of light pollution ruining our night skies. The moon is bad enough. Vist http://www.darksky.org/ for more info.

Crazed Rabbit

Xiahou
10-03-2005, 02:31
Good ideas, RH. I'd known they saved energy, but never did the math on it. The heat levels in my claustrophobic PC room is something I can definitely relate to.

Do they, by chance, make 2 or 3 stage spirals?

Red Harvest
10-03-2005, 02:31
I will back this one up as it is something I did a few years back. I didn't do it so much for the energy savings but I simply got tired of buying lightbulbs all the time. For some reason at my previous residence incandescents would just not last long at all. I think so far I have had two bulbs out of six that were about six years old burn out. Which is great considering my normal bulbs were lasting about 2 monts or so.

One thing I've seen burn out standard bulbs out really fast is cold temps. It's almost like the filaments go through some sort of transition zone temperature wise that makes them brittle. The heating/cooling cycle must be hard on them. When flipping on lights in sheds, barns, or homes that are at or below freezing, I've found the bulbs tend to have very short lives.

Another thing that can get you is if the voltage to the house is varying a lot. I had some problems with the service wiring in a house once, the voltage would swing around over a range of about 5 volts at times, particularly when the washing machine was running. The lights were dimming and brightening in cycle with it. Couldn't have been good for them, as I changed out quite a few bulbs.

Red Harvest
10-03-2005, 02:49
Good ideas, RH. I'd known they saved energy, but never did the math on it. The heat levels in my claustrophobic PC room is something I can definitely relate to.

Do they, by chance, make 2 or 3 stage spirals?

I'm pretty sure I've seen some 3 ways. The top setting for 3 ways is like 150 Watts if memory serves (for a standard incandescent.) As you go up in voltage on the spiral compact fluorescents, the length and radius of the spiral tube gets larger. The 60 W equivalents were rather small, the 100's are about the same size as a standard bulb (but with the spiral sticking out maybe 1/4" farther on the ends) but the 150's were fairly large. I suppose they get a given luminescense per inch of spiral length, which requires finding ways to squeeze more tube length in a given geometry (increase radius, and/or numbers of turns.)

Seamus Fermanagh
10-03-2005, 03:26
OUtdoor bulbs do have shorter service lives. They also tend to be left on for longer stretches.

I liked the tip about shadows. I remember playing flashlight tag as a kid and hiding in plain sight a few times that way. You were always a better hunter if you covered the light and used it only for "tagging," otherwise your vision was nerfed.

Seamus

Red Harvest
10-03-2005, 04:51
I liked the tip about shadows. I remember playing flashlight tag as a kid and hiding in plain sight a few times that way. You were always a better hunter if you covered the light and used it only for "tagging," otherwise your vision was nerfed.

Seamus

If you hunt right, they won't see you either as long as you leave the light off and know how to move silently without russling leaves, etc. It's easier to hunt humans when they can't see you. You don't want to do what my brother did though. He ran up onto some resting cattle that he thought was a person hiding. Talk about a stampede! The rest of us had to tuck behind trees for cover as the herd ran by.

One thing you need to do when you are trying to see something in the dark, breathe! If you hold your breath, your night vision fades until you breath again. This is important for astronomy, as you get to concentrating on an object and hold your breath at times as you adjust focus or move the field, etc. If you take a few full breaths you can see more of dim objects. Also, use averted vision. Your highest visual acuity is not at the center of the field but slightly offset. It takes some practice to find the sweetspot.

Xiahou
10-03-2005, 06:38
Your highest visual acuity is not at the center of the field but slightly offset. It takes some practice to find the sweetspot.Yeah, that's definitely true. It has to do with the rod and cone photoreceptors in your eyes. Rods see black and white and give better night vision, while cones see color and work better in light. Cones are greatest in concentration in your center field of vision where rods are densest more on the periphery...:book:

Seamus Fermanagh
10-03-2005, 13:53
Yeah, I always found it easier to pick up motion by purposely not focusing on anything. You saw the motion off-center, but you rarely missed it.

Seamus

Don Corleone
10-03-2005, 14:16
The only problem I have with flourescants (and we use them quite a bit) is they're not good for rapid use lights. They're perfect for a kitchen or a den where you're going to be in there for a while reading or some other activity. But if you want to walk into a dark room and have it bright, then turn around and walk out again, such as in the bathroom or a closet, I find I'm frequently done washing my hands before the light is all the way 'on' (reached it's full brightness). We still use flourescants in these rooms, it just annoys me.

drone
10-03-2005, 16:13
I've been switching out normal incandescents for these for a while now. Costco sells both 60 and 100 watt equivalents. The difference in heat is very noticeable, this was the main reason I started switching over to them. They do sell them in floodlight style bulbs as well.

Do not put them on dimmer circuits, even if you leave the dimmer on full blast all the time. If the dimmer kicks in, the bulb's regulator circuits will blow. They do take a while to get to full brightness, so as Don said, quick on/off lights aren't ideal. This might also affect the bulb's lifespan, but I'm not sure of that.

Hopefully they can figure out a way to get them to work with dimmers. I have interior flood-type fixtures on dimmers, these are the main lighting source in the family room. They would be really helpful to keep the heat down in that room.

Red Harvest
10-03-2005, 16:47
The time delay varies from manufacturer to manufacturer. I've got two different brands: GE and a generic that Home Depot was selling. The generics are almost instantaneous (less than a tenth of a second.) The GE's take slightly over 1 second--it looks like an eternity when they share the same fixture together.

TonkaToys
10-04-2005, 14:13
On a related but slightly off-topic matter, if you are in the UK visit http://www.ecotricity.co.uk as they will match the price of your local supplier and guarantee that the electricity supplied to you comes from green sources.