Lamps in T8 Lights

[Paco]

When I bought my current store over 2 years ago, one of the first things I did was change from t-12 to t-8 lighting. 100% improvement. I even changed the landlords fixtures on the outside canopy. At night, my store is light up like a Christmas tree! Customers love it. During summer months, I remove 2 of the 4 lamps in each 8 ft fixture. There is still plenty of light, and it gives a cooler appearance. I have been told there is no real money savings by doing this, due to the fact they have electronic ballast, and being efficient already. Any truth to this??? I know there are a lot smart people on this form. Call me simple, but it just seems to make $ent$.

[Duane]

Best way to check is to wire one fixture with a plug and use a Kilo-watt meter to verify the amount of electric used.

[Howard]

Makes no sense to me, but what do I know. That implies that there is no cost to light that bulb, and we all know it takes electricity to generate light. Common sense says if you remove a bulb there is less power consumed.

[chslaundry]

IIRC, there is no real energy savings from removing bulbs if the ballast is magnetic because the ballast will still be drawing current. to save electricity, you'd have to actually disconnect power. on the other hand, the newer electronic ballasts will shut off if they're not powering bulbs, for example, ones that have burnt or have been removed.

[MrMachine]

I was told that if you have the electronic ballasts (which you must have to run T-8's) you save about 24 watts by removing one 32watt bulb.

[Paco]

Now you understand the confusion. Thanks for all of your input.

[Howard]

Originally Posted by MrMachine

I was told that if you have the electronic ballasts (which you must have to run T-8's) you save about 24 watts by removing one 32watt bulb.

That seems strange too. Unless these are some type of new energy saving bulb that gives 32 watts of light for only 24 watts I would expect the savings to be greater than 32 watts not less. I would expect you would save a full 32 watts from not lighting a bulb which consumes 32 watts PLUS some saving from the ballast which is now operating at less than 100% capacity. I guess the best way to find out is with a meter, but perhaps someone with first hand experience can chime in as to why this might be different than what the laws of physics seem to imply.

[MrMachine]

Originally Posted by Howard

That seems strange too. Unless these are some type of new energy saving bulb that gives 32 watts of light for only 24 watts I would expect the savings to be greater than 32 watts not less. I would expect you would save a full 32 watts from not lighting a bulb which consumes 32 watts PLUS some saving from the ballast which is now operating at less than 100% capacity. I guess the best way to find out is with a meter, but perhaps someone with first hand experience can chime in as to why this might be different than what the laws of physics seem to imply.

Howard,

You could very well be right. I was told this by an electrician, but I'm not so sure he is right.
In any event, we know that there HAS to be some savings. Whether it is more or less than the 32 watts is debatable at this point unless someone has clear evidence.
A good thread Paco!