If you have looked into LED lighting at all you will have noticed there is dozens, if not hundreds, of options. So, as you can imagine, there a dozens, if not hundreds, of variations to the answer of this question. They range from 100W to 1500W, big fins, small fins, fan assisted, metal pressed, die cast, white powder coat, black powder coat, COB’s, small chip LED’s, high efficiency LED’s and so on and so on. Your head begins to spin at the options, but one thing you can be sure of is that LED is the most efficient – right? Wrong. Or more correctly – potentially wrong.
Let’s just confirm that point quickly as it is really important - just because it is LED does not mean that it is energy efficient. Or, conversely, just because it is old technology metal halide does not make it inefficient. A number of factors need to be assessed to decide if LED is going to work for you. How often are the lights used, and for how long etc. etc.
So let’s look at some of these factors in a bit more detail…
How often are the lights used and for how long?
A while back we had a client insisting on looking at LED. They ran a rodeo once a year for one night and he felt LED was going to give him the best return on investment because if ‘was the best’ and ‘the latest technology’. Needless to say we were dubious. The LED fittings he wanted cost 4 times that of metal halide and the amount of electricity used in the year would have only been 10’s of dollars because of only being used once a year. In this case there was no way of justifying the purchase. On the other hand, making a 40% energy saving on 100’s of hours of use per year can make it very viable.
How many lights will I need to use?
The only way to conclusively check if there is a gross energy saving is to get a lighting plan done. If you are using the existing poles then you can figure out what lighting levels you already have and get a comparative study done using LED. You can immediately see if you will require more or less fittings and energy by the layout results. Don’t take this as a given that LED will reduce your energy consumption. Most systems are less efficient than their traditional alternatives.
Optics and field size
The larger the field, the more difficult it is for LED to improve on power consumption. This is because many of the LED optics are not optimised for big field sports and are therefore very inefficient at distributing the light, particularly at a distance. The critical factor is the control of the light with optics or reflectors as this determines ultimately how many LED watts will be required. Again, a lighting plan using the IES file for the specified light is the only way to know if it will work or not. Don’t baulk at this step. It may cost a few hundred dollars at worst, and at best could save you hundreds of thousands in wasted investment.
To conclude then, efficiency is relative to the size of the investment vs the usage of the lights. Assuming you get a really good optic and can replace your metal halide fittings and get a 40% saving in electricity, make sure you get a sensible return on investment by looking at the whole lifetime cost, rather than just focusing on the isolated factor of energy consumption.