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Lowering electricity bill replacing fluorescent lights

While I was looking electricity bill for the first time of the company I work, I was surprised how much they pay. $3000 per month and $5000 during summer. Even it's not during the summer, this 50 employee two story building seems spending much.
I measured usages on computers, I ended up on around $600 including servers a month.
Now when I noticed they have lots of fluorescent lights, 4 lights in on mounting bracket, every 5 feets in the hall way and 4 lights every 2 feets in room. I need to take out 2 of 4 and also maybe recommend to replace the fluorescent lights with energy savings.
I looked at the stroage room, the maintenance guy seems using T8 (32w, Syvinia 2800 lumens ) and T12(40w Philips) lights. Does 32w light actually use 32w all the time?


And each light mounting bracket has two ballasts. The maintenance guy seems he doesn't understand what ballast type is in there and use either T8 or T12 lights. First, I'm not sure if it's safe to interchange light type different than the ballast in the bracket. I think I have to open the cover and see each ballast type in it to find out. If the ballast type is T12, can I use T8 light on it or should I replace with T8 type ballast if I want to replace T12 to T8 light?

I'm not an electrician, but feel there's something we could do to lower the bill.
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crcsupport
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crcsupport
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viki2000Commented:
I dare to say that I know quite a lot, but never enough, about lighting, particular fluorescent lighting, tubes, energy saving lamps and now LEDs. I worked in the factory where the fluorescent lights are manufactured. Particularly I worked for Sylvania, but not the US which belongs to Osram, the Europe region...anyway, I could speak with you easy minimum 2 hours on the subject of lighting, not to mention that in the past I use to calculate for entire factory the electrical energy bill in advance in order to get some discount. There is a lot to say and I do not know how much time I have. Tomorrow night I fly again in another country, but luckily this time for holiday...

1) How do you know that the rest of the bill 3000-600 is strictly related with the lights only?
2) Could you make a list and count the fixture and the number and wattage of tubes in each fixture?
3) Do you have a watt meter or at least an ammeter (clamp meter) to take real measurements of the lights on each room/floor?
4) When you speak about lowering the electricity bill, what are you ready to do? Are you ready for an investment in changing the type of lights? That investment will pay itself in the next year when proper lights are chosen from electricity bill.
Or do you only want to get rid of some lights?
How do you know if you take off some tubes would be still enough light in the offices? Can you measure it? Or is just a naked eye approximation?
5) If you do not plan to change anything as new LEDs lighting instead of fluorescent tubes, then you have to know few things:
a) The fluorescent tube has a very long life time when has a proper driving circuit. But has also an end of life. Then the light reduces. Under such conditions you should replace the tubes with new ones.
b) It is very important to know how the fluorescent tubes are driven: with an electronic ballast or with magnetic ballast and starter.
c) If the the tubes are driven with magnetic ballast, then you should change the starter from normal glow starter with an electronic one.
d) The combination magnetic ballast - electronic starter is the best driving method, despite all the other claims with electronic ballast.
e) Then comes the efficiency. Here you should use T5 tubes, high-efficiency and long life.
f) f you plan to switch to LEDs, then you should think twice, because the fluorescent lamps still give the best light/square meter with regards to efficiency, lifetime and price.
I need more input from your side to give you the proper advice.
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PerarduaadastraCommented:
Well, although the lights might need some attention, a major consideration is the large difference between the summer and winter power costs. The cause clearly isn't the lights; if it was, the shorter daylight hours in winter would cause those bills to exceed the summer ones.

My guess is that the summer increase is due either to the use of air-conditioning, or to staff members using fans when it's hot.

As for the lights, assuming that they are standard switch-started units, if you were to replace them with their HF (high frequency) equivalents, you would cut lighting power consumption by around 25-30%, and the tubes themselves would require replacement much less frequently, thereby saving more money. HF fluorescent lighting is flicker-free and also starts almost instantly compared to switch-started ones; mine still do, five years on, and the tubes are the originals...
The downside is that HF fittings are more expensive to buy, especially those that use good quality HF control gear, but economy of scale and increasing demand mean that the price difference is much less now than it used to be, and many manufacturers have ceased production of the old switch-started fluorescent fittings or are in the process of doing so.

I have no experience of LED "fluorescent" lighting, but just looking at the light output of the units you provided the link to (as opposed to their power consumption), it's around one-third that of the existing equipment. That's rather dim...

Judicious placement of good HF lighting seems to me to be a better solution in your situation than a larger number of low-power (and hence low-light) fittings.
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viki2000Commented:
@Perarduaadastra
Allow me to disagree with a good part of what you mentioned.
First of all there are no such kind of HF Fluorescent light and  other types.
All fluorescent lights can be driven at low frequency as 50/60Hz using a magnetic ballast and a starter or in high frequency, typically 20KHz using an electronic ballast.
The standard for fluorescent tubes is IEC 60081 and provides detail information about the length, type, current light, voltage...for each type. Important to mention that T5 are specified for high frequency only, but in reality we can drive them at low frequency too and we can get the same light output with less input power by reducing the input voltage.
We made a demonstration for such situation at Light&Building Frankfurt 2014  
Not only the HF tubes are flicker free. That is totally wrong.
A fluorescent tube driven at low frequency with magnetic ballast AND an electronic starter is also flicker free and is BETTER than electronic ballast. The electronic ballast has the lifetime lower than the magnetic ballast or electronic starter.
I worked for a company making the electronic starters for fluorescent lamps and the warranty is minimum 10 years for the starter. The warranty for electronic ballast is 50000 hours based on the lifetime of the electrolytic capacitor inside the ballast. In reality, good electronic ballasts made by Philips, Osram, Tridonic, Helvar...speaking about Europe, still die when are mounted in the top of the ceiling in factories or anywhere where the heat affects the electronic components inside. With magnetic ballast and the electronic starter there are no problems. They work -40°C up to 125°C, IF are the good quality. I designed such kind of starters and passed all the severe requirement posed by the EN standards and VDE german test house.
I can say a lot about this theme, including the part with standards, in the past I used to test electronic ballast, so I know enough...but I do not think make any sense..,
Sometimes you may have heard about long life tubes as 80.000 hours. Important to know that such kind of tubes are sold only together with specific starter to ensure such long life. Th trick is the energy in the filaments, very precisely calculated and the starters chosen for such compatibility.
The preheat time is very important to not be short. A good preheat time is around 2s or a bit more. The standard for electronic starters used in fluorescent tubes IEC 60927 specify the preheat time between 0.4s and 3s, but in reality a value of 2.3s for a T8 58W will give a long life time.
There is more: number of pulses, peak of the pulse, current on each pin of the tube, end of life protection...
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viki2000Commented:
@crcsupport
Could you tell more about your lamps? Their type?
For example you mentioned:
 T8 (32w, Syvinia 2800 lumens ).
Is this Sylvania Osram USA? Then what code and light color has? Yous should be able to see that printed on the lamp near one of the cathodes.
Maybe something from here will help you to identify the lamps:
http://assets.sylvania.com/assets/documents/FL083%20OCTRON%20XP%20XL.bc74ac49-8157-44fa-8138-461c57ffc768.pdf

T12? The old dragon? Get rid of it.
In order to do something with the lights, you have to know their type, the fixture, the driving methods.
Just easy check if the tubes show any signs of end blacking, near cathodes.
If yes, then they come close to the end of life. That means less output light and higher consumption.
Then you have to check if are driven with starter or electronic ballast. Sometimes is difficult to see from outside. Depending by the type of the fixture, the starter socket can be seen when the tube is mounted pr sometimes is hidden and only with power off, the fixture has to be opened, its reflector lowered and see the circuit inside.
The bad fixtures are those which have the socket for the starter or the electronic ballast right under the cathodes of the tubes. Then all th heat from the cathodes of the tube will go t the starter or electronic ballast and will lower the life time a lot
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PerarduaadastraCommented:
@viki2000:

Feel free to disagree! It often makes for a fuller discussion, and I'm always willing to learn something new.

As for making sense, your English is vastly better than my electronics...

Your technical knowledge on this subject is clearly much greater than mine, based as it is on industry experience, so I bow to its superiority. However, my observations are rooted in my (limited) experience of using both the older switch-starter type and the newer HF kind (for so I consider them, especially in view of the difference between 50/60Hz and 20KHz). Simply changing from the former to the latter made a considerable difference to my working environment, including the huge improvement made by the absence of subliminal flicker, and the fact that I haven't even had to change a tube. The switch-starter fluorescents in my kitchen are fairly horrible by comparison, with tubes and starters having to be changed several times in the period that my HF fitting has been in service.

From a technical standpoint my previous comment has proven to be inaccurate on several counts, but I think that the suggestions I made are still useful even if the basis for some of them turned out to be flawed.
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viki2000Commented:
To briefly answer some of the questions:
"If the ballast type is T12, can I use T8 light on it or should I replace with T8 type ballast if I want to replace T12 to T8 light?"

You cannot use T12 ballast with T8 lamps.
You must use T8 ballast with T8 lamps.
Only by a special coincidence it might that possible, but generally not.
More than that T8 ballast: you cannot use T8 ballast for 58W with a T8 32W lamp.
You have to match the power of the lamp with the power of the ballast.
You did not say what kind of ballast: magnetic or electronic.
The ballast has to functions: one is to create high voltage pulses together with the starter and second is to limit the current in the cathodes and in the lamp. If the magnetic ballast is rated too high or too low then you either do not give enough current in the lamp, meaning less light or you force the lamp over its parameters.

"Does 32w light actually use 32w all the time?"
No.
Not when is in dimming mode.
Not in the beginning when you start the lamp, usually takes more. It needs a stabilization time of 2-5 min up to 15-20 min depending by the ambient temperature (especially is bad when is cold), input voltage and IF the lamp is new, unused or was kept in dark for a long time.
Then depends if the driving method is 20KHz or 50/60Hz.
Then depends if it is at the end of life or not.
Then you have loses on the magnetic ballast, which requires a capacitor for compensation of the power factor, reactive energy.
In case of the electronic ballast, you have to check if has power factor correction circuit to offer over 0.9 values, then look in the datasheet of the ballast for efficiency.
Only afterwards you may ask if the 32W written on the lamp is really 32W consumption.
That's why I said in the beginning that is easier to direct measure the consumption at power distribution panel with 100USD or cheaper clamp meter.

I am sorry I cannot stay more, I have to go and prepare myself for holiday...
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viki2000Commented:
A friend of mine working for the German Cooper Institute has a nice tutorial here about the fluorescent lighting:
http://www.leonardo-energy.org/lighting-tutorial
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nobusCommented:
i would first make certain that the electricity bill is caused mainly by the lighting -and not by anything else, like Airco, heating, or other  devices (motors)
make up a power list of all electric devices, - a Kill-a-watt is useful here : http://www.p3international.com/products/p4400.html

or consult the electrician, and the installed Devices list
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aleghartCommented:
I'm doing load calcs now on building power (generator backup).  The HVAC load is higher than all the other loads combined, including servers, desktops, and lighting.

If you winter bill is lower, you are probably using gas heat, not electric heat.

What size are your air conditioning units?  You can estimate (read "guess") a load based on roughly 1kW per ton or per horsepower.  If your estimated HVAC running load is 50 tons (50kW), that would be equivalent to 400 fixtures with 4x32W bulbs each, or 800 fixtures with 2x32W bulbs.

In my immediate office space, I have qty=20 x 2-bulb fixtures in 800 square feet.  By rough-guess, I'd cover 160,000 sq.ft with 2-bulb fixtures before I hit the same load as a 50-ton unit.  Trust me....you'd need closer to 500 tons to cool that much square footage here in southern California.
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crcsupportAuthor Commented:
1) How do you know that the rest of the bill 3000-600 is strictly related with the lights only?
I measure kWh of each model of computers we use for 24 hours and putting it to hours of work, it came with the numbers;
Dell Optiplex Core2Due: 0.7 kWh per hour
AMD 8 Core: 0.8 kWh per hour
Monitor 19", 24" monitor: 0.3 kWh per hour
Canon Image Runner multi function printers: uses 0.2kWh per a business day.
etc...

Electricity Supply Charge: 10 cent per 1kWh(it changes seasonally but 10 cent seems average)
Electricity Deliver Charge: 10 cent per 1kWh(it changes seasonally but 10 cent seems average)
I'm reluctant to give list of our IT infrastructure in this public space, but the above is what I used and the kWh was measured using Kill-a-Watt I bought in ebay at $22.


2) Could you make a list and count the fixture and the number and wattage of tubes in each fixture?
Fixtures: 109
32W/40W Sylvania or Phillips Fluorescent light tubes on each Fixture: 4
1588 Watt In-wall cool/heat air conditioners: 4
Central Air conditioner: we have air conditioners controlled centrally, but have no information about this.


3) Do you have a watt meter or at least an ammeter (clamp meter) to take real measurements of the lights on each room/floor?
No. I assumed if a light shows 32W and if we leave it on, it may consume 0.032 kWh per hour.

4) When you speak about lowering the electricity bill, what are you ready to do? Are you ready for an investment in changing the type of lights?

After I measured and calculated electricity usage of IT devices, I made a note to employees to completely turn off computers and monitors when they leave for work and put printers to saving mode and have them to use an application to turn on/off their own computers(Wake On Lan) if they remote, which, in my calculation, will save $350 leaving the total usage cost of our IT infrastructure to $600 per month.

Or do you only want to get rid of some lights?

Yes, I think I have to go around offices and deal with them to take out 2 light tubes from each fixture, which will save 64W-80W per each fixture.

How do you know if you take off some tubes would be still enough light in the offices? Can you measure it? Or is just a naked eye approximation?

Just my assumption looking at brightness of the room. Some rooms get sun light from window, so I think it's possible, supervisors in the rooms agree on taking out light tubes.


5) If you do not plan to change anything as new LEDs lighting instead of fluorescent tubes, then you have to know few things:
a) The fluorescent tube has a very long life time when has a proper driving circuit. But has also an end of life. Then the light reduces. Under such conditions you should replace the tubes with new ones.
b) It is very important to know how the fluorescent tubes are driven: with an electronic ballast or with magnetic ballast and starter.
c) If the the tubes are driven with magnetic ballast, then you should change the starter from normal glow starter with an electronic one.
d) The combination magnetic ballast - electronic starter is the best driving method, despite all the other claims with electronic ballast.
e) Then comes the efficiency. Here you should use T5 tubes, high-efficiency and long life.
f) f you plan to switch to LEDs, then you should think twice, because the fluorescent lamps still give the best light/square meter with regards to efficiency, lifetime and price.
I need more input from your side to give you the proper advice.

Can you recommend any T5 light tube and does it require to replace our current ballast which works with T8/T12 light tubes we currently use?
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crcsupportAuthor Commented:
@viki200040W T12 Sylvania
Could you tell more about your lamps? Their type?

40W T12 Philips
40W T12 Philips
40W T12 Sylvania


32W T8 Topaz
32W T8 ToPaz
Pictures attached.
Questions, So can I use T5 light tube on Fixture where T12 light tube used? I will take pictures of Ballast used on T12 light tubes and post here later. But our maintenance guy seems he just plugs T8 light tube to whereever it fits, and we had no problem so far, so I assume T8 works on T12 balllast. He said, initially he didn't see any T8 light tube when he started working, so all ballasts seem T12 capable. I will post pictures of ballast tomorrow.

Currently, I think in two or more steps to save energy on light tubes.

1. Take out 2 light tubes from each fixture if supervisors in the room agree. If they complain, we put back light tubes

2. Replace T12 light tubes with T5 or T8 light tubes. I need recommendation for T5 light tubes. Picture for ballast will be posted here later, I am not at the site, that's why.
After I posted the answers, I found some answers to my question from your comments. So if I want to use T5 light tube, we have to replace ballast and in this case I have to go out sourcing to do the job. 100 fixtures!
T12 and T5 is big different in terms of diameter. What about the brightness of two? If I replace with T5 tubes, then I may plug t light tubes in each fixture which ends up the same total cost of electricity usage per each fixture;
A. 2 X 40W T12 Light tubes
B. 4 X ??W T5 Light Tubes
Is B better for electricity usage? And what about brightness?
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aleghartCommented:
3. For summer usage, our total bill gets $2000 more than March-May bills. This is something I can not control, but any recommendation I can do besides reducing the target temperature in the room? The temperature is already scheduled to change during business hour and nonbusiness hour through program.

Tint the windows with reflective material.  Close the blinds.

Replace insulation batting above your drop ceiling that has been displaced.  It's not as efficient as insulating the roof, but if the batting is already there...make sure it's actually covering the ceiling, not piled up by workers who were working in the overhead.  After a few years, there is so much displacement, it's not very effective.



There are a few more important things you haven't addressed:

1. how is the building laid out?  Can you put plantings, lattice, or screens to reduce the sunlight on outer surfaces of the building?  Shade the windows?

2. how are you billed for electricity?  usage-based, or maximum-demand rate?

2. what are you doing for your house HVAC.

If it's a multi-compressor system, you're better off starting earlier in the morning and only running half the system.  Let the full system come on only as necessary.

When you both loops of a multiple-pump system, your peak is higher.  In maximum-demand rates, your highest usage is taken, and you are billed flat rate based on that demand.  So, if you are running all lights, computers, servers, spot AC, and house HVAC at 1-2pm...that will be your maximum demand.  You'll be billed at that level for the month, regardless of how much power you save for the other 23 hours of the day.
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crcsupportAuthor Commented:
@aleghart

1. how is the building laid out?  Can you put plantings, lattice, or screens to reduce the sunlight on outer surfaces of the building?  Shade the windows?

:Yes, there are rooms with great exposure to sunlight and they like to enjoy viewing outside scenery. For this recommendation and others of you stated above, I haven't really thought of doing it all. I think I have to inspect all rooms and start planning to do so.

2. how are you billed for electricity?  usage-based, or maximum-demand rate?

:I spent quite of time to understand how ConEd bill and how they charge. I still don't get how Demand supply turns to $940 and what the threshold they use to determine what's considered to be Demand Supply , but obtaining load factor, 47%, we seem using electricity much more at peak time.
Below is July bill, Summer. On March-May, Energy Supply & Delivery cost is about 65% of July and Demand Supply & Delivery is about 50%.

July ,2014 ConEd bill:
Your Supply charges:
Energy supply 20,800 kWh $1,235.75
Demand supply 57.6 kW $940.65

Your delivery charges:
Energy delivery 20,800 kWh $702.65
Demand delivery 57.6 kW $1,375.09

Load Factor formula:
[kWhrs / (# of days in billing period x 24 hrs x billable demand [kw] ) x 100 = % LF]

My Load Factor:
28,000kWh / (32 days * 24 hrs * 57.6 kW) * 100 =47.1%


3. what are you doing for your house HVAC.
If it's a multi-compressor system, you're better off starting earlier in the morning and only running half the system.  Let the full system come on only as necessary.

: I have to talk with our maintenance guy if he can do this. Thanks for the tip.
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aleghartCommented:
Your "demand", IIRC, is based on your peak usage.  So, that would the hottest hour in the summer months, or the coldest day in the winter if you're using electric heat.

You may not be able to get that number down without managing the air conditioning.

We have a controller that sequences equipment so the amp loads aren't too high from simultaneous startups.

Your shutting down computers at night might help with the kWh delivered.  You'd be surprised how much it adds up to over the course of a year.

VMware has power management that will migrate VMs onto fewer hosts at night, then shut down the hosts that are unused.  Saves power, and saves HVAC.  In the mornings, the hosts power up and the VMs move over.

Don't forget shutting of lights at night (leave emergency lighting on)...or use motion sensors to turn them off automatically.  Turn the bathroom lights off.  See if the outside lights can be replaces...they will burn for 12+ hours/day, 7days/week.
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crcsupportAuthor Commented:
@aleghart
Our VMs are all based on Hyper-V. We're still in the process of converting to virtual environment for servers. Our business is based on agents taking calls and for security reason, agents must work in our site. But it's still surprise to know VMWare moves VMs daily between hosts. Is it possible with Hyper-V failover? I only considered the feature as failover purpose, but not like moving VMs daily between hosts as  you described
Motion sensors are in place for bath room and some hall ways. I think I may look more to change. Thanks for the tip.
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aleghartCommented:
DRS - distributed resource scheduler
DPM - distributed power management

Managed from VMware vCenter, depends on version and licensing.  It's been around since ver.4.  Must be running in a cluster with similar/compatible hosts.

Not aware if Microsoft has anything similar in Hyper-V.
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crcsupportAuthor Commented:
Thank you everyone all great information how to save energy. We went through replacing ballasts and light tubes from T12 to T8 last Sunday. We took out two light tubes leaving another two instead four in each fixture.
With this installation, I will go through all the recommendations you suggested and evaluate, then I hope I can implement as much as possible.
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