Metal Halide vs Fluorescent

[GuOD]

I just had a quick question about these lights because we don't understand the ratings.

I've heard that MH will drastically increase utility costs each month. However, we've noticed some fluorescent bulbs have the same wattage rating as Metal Halide.

For instance, how would a 160w compact fluorescent compare to a 150w metal halide on power draw? In this case, would the metal halide actually use less power and cost less than a fluorescent?

Thanks!

[roka64]

I am not an expert on MHs, actually I just bought my first set of MHs. To answer your question, the MH will draw more power than CFs. I am probably wrong on this, but it may have to do with amps and not watts....some one can probably explain correctly. I was just taking a quick shot, to see if I have at least a basic understanding....

[GuOD]

Originally Posted by roka64

I am not an expert on MHs, actually I just bought my first set of MHs. To answer your question, the MH will draw more power than CFs. I am probably wrong on this, but it may have to do with amps and not watts....some one can probably explain correctly. I was just taking a quick shot, to see if I have at least a basic understanding....

Thanks. That was my assumption too.

My computer power supply is 700w, but it doesn't even draw close to that majority of the time. I was assuming the wattage rating is something like peak and then the Fluorescent has a 50% draw while MH is probably closer to 100% or something.

I could be totally off on that though

[rubikcube]

From what I am told by my electrical engineer friend, the rated wattage is what is used. Therefore the 150 watt MH bulb will use slightly less power than the 160 watt bulb. However, the MH should put out a lot more lumens as a result of it being more efficient.

[roka64]

But does it draw more power?

[rubikcube]

Watts = Power, so 150 watts is less than 160 watts means the 150 uses less power.

For example, look at the self ballasted compact flourescent lamps they sell now. They have far lower wattage ratings than the old incandescent bulbs they are replacing, yet produce the same amount of light.

[roka64]

Hmm, ok, so why does your electric bill go up with MHs? I'm not trying to argue, just trying to learn, it seems there is something I am missing....(maybe part of my brain! LOL!)

[rubikcube]

Go up compared to what? Compact florescents, T5 HO?

From what I've seen, most MH fixtures come with supplementary actinic lights. This causes the total wattage of the fixture to be quite high.

Also, from what I understand, the particular ballast being used on the fixture has an impact on the efficiency of the lights. So an inefficient ballast might waste more electricity. I'm just speculating though.

[roka64]

Ah, ok, that makes more sense. I was saying some folks don't use the MHs due to the increase in the bill, from VHOs or PCs, but since the MHs coupled with the other lights, the bill would go up due to the combined wattage. THANKS!

[john0087]

My friend works for the power company and I asked him the same question. A watt is a watt, no matter what. The power company bills you in watts per hour.

The largest PC bulb (in an aquarium fixture) that I have seen is a 130w.

Lets say you had a fixture that had 4 130w 36" lamps, thats 520w. Now consider that in the same space, you can have 4x250MH bulbs, or even 4x400MH bulbs. Thats a lot more power, hence a bigger cost.

Also, if you have noticed, most of the higher watt PC's are longer. I have been looking for a 24" PC bulb that is more than 65W. The increase in watts produced by the PC is, I think, a function of how long the buld is. That is to say, a 130w 48" bulb isn't really brighter that a 65w 24" bulb, it just covers a larger area. Whereas, you can get MH bulbs in 150; 175; 250; 400w for the most part, are all the same size.

My point being, the cost to run MH's increase beacuse you can increase the amount of light power for any given space.

hope this make sence.