Sam Woodward, Customer Education Leader, Europe and Africa at Lutron Electronics
LED lights have been around for decades but only recently found their way into the commercial sector as organisations increasingly looked to reduce excessive energy consumption.
Earlier this year, IKEA became the first retailer to announce it would no longer sell halogen replacement lamps and would switch entirely over to stocking energy efficient LEDs instead. Not only that, but in a move to become even more energy efficient and environment-friendly, the company also revealed plans to change its entire lighting store line up to LEDs by 2016. Behind the scenes, IKEA is also working with suppliers to improve the environmental impact of the LEDs it stocks and the corresponding price, positively influencing its supply chain at the same time.
This move puts IKEA well ahead of its time and makes it one of the first companies in the retail sector to implement fundamental stock changes that encourage the use of alternative, more energy efficient lighting solutions. This is inevitable though as the EU’s 2020 initiative is set to impose a total ban on halogen lamps by 2018.
But IKEA isn’t the only company that is taking the matter of energy efficiency seriously. Other retailers are also switching their in-store lighting systems to more environment-friendly alternatives. British high-street retailer M&S, for example, has made steps to reduce its energy usage by bringing LED lighting to every M&S Simply Food store in order to comply with the EU’s 2020 energy programme.
LEDs as the most efficient light source
LEDs have now become the alternative to halogen and fluorescent light sources as they are considerably more energy efficient. To truly understand their benefits though, it is important to know a little bit more about how they work, how they are controlled, and where there is still room for improvement.
As with many light sources, an LED produces light when electric current flows through it. For general lighting purposes, multiple LED chips are grouped onto an array, often called a “light engine”. As well as traditional “light bulb” shapes, these now come in many different form-factors, enabling exciting new shapes of light fixture. Additionally, when compared to more traditional lamps, LEDs also have a significantly longer life expectancy, lasting tens, or even hundreds of thousands of hours – that’s over 13 times the length of an average halogen light bulb, previously found in some lighting systems. Despite some initial challenges in retro-fitting LEDs where existing controls have been kept, their benefits are huge and have caused a real paradigm shift in the lighting industry.
But while IKEA’s determination to only use and stock LEDs from 2016 onwards is certainly admirable, it is only the first step on the road to greater energy efficiency for any company. Two other factors, namely driver efficiency and control of each light source (to switch it off or dim it when it’s not required), make up the other equally-important parts of the trinity of efficient lighting solutions management. A three-fold approach is always necessary to become truly energy efficient.
A driving force behind the scenes
When looking at lighting systems and how they can be improved, many people purely focus on the light source itself, opting for more efficient lamps with lower wattage ratings. However, a substantial part of the system sits ‘behind the scenes’ inside the walls or connected to the actual lighting fixture in the form of the driver.
Drivers (more correctly called the “Electronic Control Gear”) are the parts of the system which convert the mains voltage to the correct constant-current or constant-voltage required by the LED fixtures. Whilst these are built-in to replacement lamps, they are often remote units in LED fixtures. They must always be matched to the light source they are connected to. But not all drivers are equal, and the variety of efficiency options in this part of the system is a surprise to many people. High-quality drivers are more than 85% efficient. Not using an adequate driver doesn’t just hinder efforts for lighting to become more energy efficient, it can actively deteriorate a whole building’s performance as inefficient drivers emit considerable heat which then needs to be dealt with by the building’s air-conditioning system. So the mantra ‘out of sight, out of mind’ clearly doesn’t apply to drivers as they are as important as light sources in making lighting systems more efficient.
Output control
With both efficient light sources and efficient drivers in place, it is also important to make sure a system only produces as much light as is needed by the user, and only when the user requires it: common sense says that the most efficient lighting system is one that is switched off when it is not needed. Users often don’t need a system’s full brightness capability. Most of the time they actually only require a certain degree of illumination. Dimmers along with occupancy sensors can be used to switch lights off completely when no-one is there.
Shockingly, only 3% of the UK’s businesses and homes currently operate dimmable or automated light systems, which means an overwhelming majority still use outdated, traditional on/off switching, wasting huge amounts of energy in the process. The potential energy savings that could come from installing sensors and dimmers into every lighting system are a key area for improvement if companies want to substantially increase their energy efficiency, promote a corporate sustainable approach and, in turn, lower costs.
It is great to see that retailers such as IKEA and Marks&Spencer are taking the lead for greener lighting solutions, but this is only the first step on the path to truly efficient energy management. There’s still a long way to go so let’s make sure we don’t forget about the other, often less visible, but equally important, elements in the lighting system, efficient drivers and automatic dimming controls that can help us make a real change in the way we manage and consume energy in the UK.
