All of us know or at the very least hear that converting from Metal Halide (High Intensity Discharge) to LED will save you money.

The questions is t how much you will save?

In this article, we damage down all the variables that you must know before choosing to convert from Metal Halide to LED. Right here, there are 9 factors we think LED will win Metal Halide.

1. Lamp (Source) Efficiency Vs Fixture (System) Efficiency

Let’s take a look at the details on a normal 400 watt metal halide bulb. While specifications might vary, a browse through to a preferred online website that sells Metal Halide light bulbs shows that a new bulb has the adhering to specs:

CCT: 4000K

Preliminary Lumens: 32,000 to 36,000

Life Hours: 20,000

A current white paper by the Dark Skies Society rated the mean lumens for a 400W Steel Halide to be 20,500 lumens and also the ranked life expectancy to be about 15,000 hrs. But also for objectives of this conversation, we will certainly stick to the numbers we are familiar with.

There is a great deal of intriguing details to consider. First lumens is a really high number, but actually, a Metal Halide light bulb starts extremely intense and then drops its lumens instead rapidly, settling in at a reduced lumen outcome rather swiftly.

It is not uncommon to lose as long as 20% in the initial 6 months alone. So while 36,000 lumens sounds excellent, within 6 months, it can be listed below 30,000 lumens. Lumen depreciation in a metal halide light bulb is relatively quick. It is kept in mind that at half life of the light bulb, around 8,000-10,000 hours, lumen devaluation is already at 50%.

Similarly, let’s look at the operating nature of the bulb. A Metal Halide bulb is omni-directional. That indicates light is dispersed in every direction. So it generates as much light flat alongside the ground as it does facing downwards.

To make this light helpful, you need to gather it, accumulate it, and supply it to where you desire it. In component design, you include a reflector to do this task. The main trouble with reflected light is just how effective is the reflector obtaining the light that bounces off of it to the ground.

A lumen that bounces off the reflector and recovers right into the fixture is thought about a loss lumen. Anything more than one bounce is throw-away. As high as 30% or better of the light can be lost in this reflective bounce.

So if we do the mathematics of a steel halide bulb in an industrial interior bay component, if we assume the first lumens of the light at 36,000 lumens, after 6 months we would certainly anticipate the component efficient lumen efficiency to be:

36,000 lumens – 20% (first lumen loss) = 28,800 lumens

Lumens loss from reflector bounce: 8,640

Overall lumens after 6 months in indoor bay component: 20,160

This does not take into consideration any kind of lenses or guards that the fixture might already have.

Remember, this is light bulb lumens, not component lumens, so anything else added that obstructs of getting light to the ground will always eliminate from reliable lumens.

Compare this to LED. If you consider a LED component or LED Fixture Retrofit Set that replaces MH and also HID technology, all the light is directional, because, it is guided to where it is needed. Reflectors are not needed. There is nothing to show.

In terms of lumen devaluation, it does occur in LED, yet it takes a lot longer for it to take place. For instance, our retrofits have a L70 (lumen depreciation to 70% of preliminary lumens) of over 100,000 hours. So where as Metal Halide sheds a great deal of lumens in the initial 6 months of life, LED tends to keep its lumens for much longer.

However there’s more to this story, checked out listed below …

2. Operating Life

As pointed out, the operating life of a common Metal Halide light bulb seems to be around 20,000 hrs. Larger bulbs, like a 1000 watt Metal Halide, are around 15,000 hrs.

In regards to LED solutions, there are different methods providers explain the life of the item. One way is to state L70.

L70 is not a dimension of end of life, however it is a dimension of lumen destruction up to 70% of initial lumens. This does not imply the driver or ballast or some other component may fall short too soon.

What we do recognize is the life of a Metal Halide bulb is about 15,000 to 20,000 hours. What we also know is that at half life, it has currently lost 50% of its first lumens. So while not dead, very inefficient.

For the document, it still consumes 400+ watts even though it is half as bright.
Compare that to our Retrofit Products ranked at 100,000 hrs (L70). So by the time the LED head gets to 100,000 hrs, you have done 5 Metal Halide bulb replacements, perhaps much more.

3. Efficiency (lumens/watt)

This is the pre-cursor to the next subject, energy savings, but the basic premise is the more efficient the bulb is, the more money you will save. So let’s calculate the lumen efficiency of metal halide versus LED.¬†

To determine lumen efficiency, you need to take the overall lumens created and also separate it by the total watts consumed.

In the case of Metal Halide, you also have to consist of ballast draw. If you recorded the total watts eaten of a regular 400W light bulb, it is around 455 watts. The ballast eats regarding 15% more power beyond the light bulb usage.

So computing lumen effectiveness for metal halide: 36,000 lumens/ 455 watts = 79.12 lumens/watt.

Allow’s compare that with our 150 watt Retrofit System: 23,250 lumens/ 150 watts = 155 lumens/watt. Almost dual of Metal Halide.

As well as keep in mind the principle: Efficiency save Money!

4. LED vs Metal Halide Energy Savings

So in the above discussion, something essential was explained.

Above we discussed the mean lumens of a 400W Metal Halide to be around 20,500 lumens.

Our 150W retrofit package produces 23,250 lumens, however as opposed to melting 455 watts, it takes in just 150 watts. That represents a 66% cost savings in power taken in to create more light.

However, we think 23,250 lumens to change 400W Steel Halide is over kill. For several years, we have actually been selling our 105W Retrofit and it’s a lot more reliable substitute, the 100W retrofit at 15,500 lumens to change 400W Metal Halide.

Here is a recent instance of a test a client did to ensure the lumen result of our 105W set would certainly be just as good as what he was presently using.

Notice: in the comparison image listed below, the LED generates so much light it casts a darkness from the pole in the light generated by the metal halide light.

5. Savings on Maintenance

Several clients wish to transform to LED due to maintenance cost savings as they do for power savings.

Think about what we discussed, over the life of the LED product, a client would need to do 5-6 bulb replacements.

The greater the installation elevation, the higher the cost of replacement. And also if you have actually a facility loaded with lights, this comes to be a substantial budget plan quantity annually that you must take into account.

Now, we know that lowered maintenance time on lights does not convert right into dollars conserved because it is very not likely that individuals will lose their tasks over the fact there is much less job to do.

However, these people will have time to currently service things that matter, like taking care of the devices that make the company cash instead on replacing lights that set you back the business money.

6. Quality of Light

When you take a dimension of light with a light meter, it checks out lumens. And also this dimension of all the lights that add to the light at that location creates a dimension called foot candles.

However let’s think of that light that is being measured. Metal Halide creates all kind of light, in all range’s, visible or otherwise. This includes UV as well as IR spectrum’s, noticeable to the measuring device yet not noticeable to the human eye. LED, on the other hand, does not produce UV and also IR. As a result, its analyses utilizing the same light meter is just picking up noticeable range’s.

So there is a fun little examination you can do. Have 2 source of lights, LED and also Metal Halide. And also initial ask, which one is brighter? And if the right LED source was picked, they ought to claim LED. And after that make use of a light meter, as well as the light meter might claim the Metal Halide area is creating much more foot candle lights. And so now you understand part of the factor, however wait, there’s 2 other items of details you need to understand.

One is called Shade Rendering Index, or CRI. It is a measurement of High quality of Light. It’s a scale between 0 and also 100, 100 is excellent.
As well as LED has a tendency to have a high CRI worth. So the other principle we say is “You need less quantity when you have even more high quality”.

Now, Steel Halide light bulbs can be great, and also are definitely much better than their High Pressure Sodium equivalents. But LED has a tendency to be far better, so we perceive the light created by LED to be brighter. Extra regarding this in the next area.

7. Photopic vs Scotopic Lumens

Years back, also the conversation of photopic vs scotopic lumens was perceived as voodoo magic talk.

There were those who relied on the distinction and as lots of who discounted it. What this is a conversation of just how we view light (scotopic) vs exactly how a video camera or light meter regards light (photopic).

It is true individuals have the ability to see, as well as light is a big component of why we have the ability to see. Stroll into a dark bat cavern as well as you will promptly recognize how vital light is. Our eyes include poles as well as cones, as well as how they work enables us to see colors and regard objects during the night.

You will certainly discover that it is more difficult to see colors at night. That is how our eyes function. Cameras and light meters function in different ways, they detect light in an entirely various method, yet what they do review they sign up as well as they analyze what it is ‘reading’.

Then researchers and physicists went along and they attempted to understand all of this. As well as they created this idea of scotopic lumens.
But after that they took it an action additionally and also determined to produce a series of elements by light of exactly how lights truly want to us scotopically versus just how a light is measured photopically.

What appeared was a series of aspects in between 0 as well as 3. Some lights efficient lumens were lowered by these factors, like High Stress Sodium. Some source of lights were boosted by these variables, like LED.
What was identified was the element related to LED was higher than Metal Halide. So in the conversation above concerning perceived light, it assists to understand why we assume LED Lights are brighter than various other source of lights, even though the light meter informs us in different ways.

8. Rebates at time of purchase

Utility firms are attempting to obtain their customers to transform to LED.


It refers economics for them. Need for electrical energy is expanding, so once they reach capability, they need to choices, construct more capability or decrease demand. Decreasing demand is much more inexpensive than increasing capability.

So the energy business provide discounts to acquire LED. They want you to transform from Steel Halide. Every utility business runs their own rebate program but as a whole, there are some regular processes and standards.

For the most part:

Utilities provide both prescriptive and also personalized refund options. A prescriptive discount is where they would certainly state a 400W Metal Halide light bulb is to be changed with a LED light bulb with these specs. A personalized refund is for those exceptions not covered by authoritative problems.

A lot of LED items require to be DesignLights Consortium Qualified. This is an icon of effectiveness and also performance. It is kind of the equivalence of Energy Star for customer items. It informs the consumer the lights are examined to a basic and also has passed.

These rebates help in reducing the expense of purchase and also eventually affect the quickness in pay back of the financial investment. With much less price at time of purchase, the moment it takes to repay the financial investment goes down with the addition of refund dollars.

With Metal Halide, no discounts. Sorry.

9. New versus Retrofit

So possibly at this moment you are believing that transforming from Metal Halide to LED is a great idea. Yet this is where the trip begins. What to choose, what supplier to deal with, new or retrofit. Think of the LED Market as the wild, wild west, and also with every weapon program there are the serpent oil salesman attempting to get you to get their lotions.

In the world of LED, there are many lotions, mistaken beliefs as well as splendid advertising and marketing suitables. For example, a well developed Retrofit Replacement Kit will certainly do as well as a new component, as well as vice versa. It doesn’t constantly make good sense to change the component, neither does it constantly make good sense to retrofit a fixture.


There you have it, 9 very backed up and legit factors the battle of LED vs MH is no longer a fight. LED is a clear winner in every facet of a light. We consider it as the ideal HID Replacement.