Technology: LED: the 2020 view
Technology: LED: the 2020 view
Elation Lighting’s Bob Mentele explores the growing list of advantages LED lighting boasts over tungsten
At this point in its existence, the overall benefits of LED lighting vs its tungsten predecessor are almost common knowledge. So much so that it’s getting harder to find anything other than an LED bulb to put in your table lamp at home. LED lighting is more efficient, requires less maintenance, emits less heat and offers more flexibility than tungsten.
These features have carried over to, and immensely enhanced the capabilities of our industry. Not too long ago, if you wanted to design a new lighting system for a worship or performance space, you had to have access to a large amount of electricity. For most moderate spaces, around a 300–400A service was required just for the lighting system. That requirement can be quite expensive and, if the building is an existing space, sometimes it’s nearly impossible to have that vast amount of power run to the location where it’s required. With a new LED system, power requirements are reduced dramatically. Typically, no more than a 100A feed is required. That amount is almost commonplace in commercial spaces, so it is usually much easier to access. Smaller systems require much less.
Another aspect you had to consider was the ability to have easy access to all of the lighting fixtures for regular lamp changes. Most entertainment lamps have less than a 1,000-hour life expectancy. New filament designs can offer more life, but it’s still vastly less than the typical 50,000-hour rating of an LED device. In some venues, lamp changes can be quite costly due to the need to rent a man lift or other access device to simply reach the lighting fixtures.
It is also important to note that LED devices do generate heat, but nowhere near the amount that a tungsten fixture emits. Tungsten fixtures must have enough airflow around them to help with heat dissipation, and to keep them from starting fires. Hanging them too close to curtains or other easily combustible material will cause issues. With all of the heat created from these lighting fixtures, more stress is also placed on the venue’s cooling system. With less heat generated from a new LED fixture, less money will be spent on the cooling costs of a space. Those figures are sometimes harder to quantify due to the number of variables in the equation, but the reduction in costs is noticeable.
New advances in LED technology also help to give us more flexibility in our systems. Most new fixtures are capable of producing not only white light, but also vibrant colours. A tungsten fixture can be coloured with the use of filter material, but it can only use one filter at a time and placing a deeply saturated colour in a fixture can reduce the light output quite significantly. LED colour-changing fixtures do not require filters, so they do not have any reduction in the light output to produce a saturated colour. They can also change immediately to another saturated colour, reducing the number of fixtures that would be required to offer multiple colours in a space.
As with almost any new technology, there are a few disadvantages of using LEDs vs tungsten lights. Some LED fixtures do not dim the output evenly or smoothly. This is typically only an issue in entry-level or less expensive LED devices, because they use lower-quality drivers, which are electrical components that convert the 120V signal to the low-voltage DC signal that the LEDs require. LED devices are also more expensive than tungsten fixtures. This cost can be offset when you also factor in the additional cost of a dimming system and ongoing maintenance costs of tungsten. Another drawback is, unless specifically designed to do so, LED fixtures are not capable of connecting to a dimming system. If an existing venue would like to upgrade their fixtures to LED, the dimming devices need to be removed and replaced with power relays, or another constant power source. While an LED system may not require dimming, that doesn’t mean they do not require power management or control of the LED fixtures. Designing a power management system that allows you to turn your products on/off is a must and should be encouraged, as LED fixtures are truly electronic devices.
Although light may not be coming out, if the fixtures are energised 24/7, it puts non-essential wear and tear on the internal electronics, so any LED system should be powered off when not in use. LED fixtures may also require that a venue replace their existing lighting control device if it is not designed to control them. They also need to have a control signal sent to each fixture, which can prove difficult in some venues. If running additional cables is an issue in a particular space, wireless options are available to make the transition easier.
With all of these advantages and disadvantages, one might ask if LED can really replicate the quality of light that we are used to getting from tungsten fixtures. That really is a loaded question, as it depends on what is most important to you and your venue. If you need a flexible, colour-changing fixture to provide vibrant or subtle washes, then an LED fixture would be a great improvement. If you want a bright, high-quality white light that looks exactly like a tungsten fixture, then you may be quite surprised as well.
Not too long ago, LED lights were not able to replicate a quality white light nearly as well as they can now. The quality of light is a measurable trait and we use the Colour Rendering Index (CRI) to do so. CRI is a measurement of light in relation to how it affects the appearance of colour. A CRI rating is represented by a number on a scale from 0–100, 100 being the best. For LED fixtures, a measurement of at least 85 is considered acceptable for most entertainment venues. Higher ratings are available for entertainment fixtures, but it shouldn’t be too much of a sticking point, unless the space has very high colour consistency concerns. LED bulbs that we use in our homes typically have a rating from 80–90. The higher the CRI, the more expensive an LED will cost, so that is why consumer LED bulbs have lower ratings, to keep costs down.
As with any technology, advances are always being made. Although LEDs have been around for a while, they are constantly improving. Manufacturers are constantly designing new emitters that are brighter and have higher CRI ratings at a more affordable price. It might not be too long before we see a 100 CRI LED become readily available.
One variable that may force the change from tungsten to LED is government regulations. The EU has been working on passing regulations that would ban the use of any tungsten or compact fluorescent lighting. Luckily, they removed entertainment lighting from the scope of the legislation through successful lobbying, showing the monetary impact it would have on small venues and artistic impact it could have on theatres or other performance areas. Although we dodged the bullet this time, there could be a time in the future when we are unable to persuade the politicians and are forced to change. Hopefully by that time, most venues will have already adopted LED and the prices will continue to drop, making it easier for those that haven’t made the change yet.
Another variable that may force a venue to change is the availability of replacement lamps. One of the largest manufacturers of the PAR lamp abruptly ended all production and recalled a large number of existing lamps due to longevity and safety concerns. The PAR fixture has been an industry staple for decades and its future has drastically changed, almost overnight. While replacement lamps can still be obtained, new sources will be hard to find, because the process to make the bulb and lens of the lamp is costly, and the machines to perform the work are scarce as well. Older incandescent fixtures sometimes require very unique lamps and, if demand for those products reduce enough, manufacturers will be forced to discontinue other models as well.
While the cost to design a full LED system is still pretty high, one could look at the process in multiple ways. If the need arose to make a change, a venue might be able to transition in phases as budget becomes available. An option is to possibly do the lights above the stage first, because those are typically the fixtures that benefit the most from colour-changing LEDs. The next phase could be all of the front lighting. Or, one could upgrade the most used fixtures first, some front lights and top lights, and then circle back and change the less important devices. The best route would be to do the upgrade all at once. That would ensure that the fixtures you choose are still available, and that they all have the same features and are not upgraded in between the time you buy them. When looking to install a completely new system, power control and lighting instruments, the cost between the dimming infrastructure and incandescent fixtures vs power relay devices and LED fixtures is getting closer every day. Incandescent fixtures are fairly inexpensive, but new dimming infrastructure is quite expensive, while power relay devices don’t cost much more than a standard breaker panel, but the LED fixtures are expensive. Add in the flexibility, maintenance costs and efficiency of LEDs and the cost difference can be negated very quickly.
Because of the constant improvements in technology, reduction of cost to purchase and flexibility of LEDs over the standard incandescent technology, LEDs are quickly becoming the preferred method of lighting in a venue. Almost every entertainment lighting manufacturer’s product portfolio centres around the use of LEDs for the illumination source because of the numerous advantages that they offer. Some still offer a handful of incandescent options because LEDs are not quite bright enough for some applications, but that will change soon enough. For those venues that are slower to adapt, it is becoming quite difficult to find incandescent fixtures to replace aging inventory. There are only a couple of manufacturers left that offer older designs in tungsten models. We may soon see a time where replacement lamps are simply not manufactured anymore, and a change is forced on us. But, in this case, the future of change is very bright, colour-changing and energy efficient.