Lighting : Lighting April 2016 - Vol 36 Issue 2
14 LIGHTING MAGAZINE | April/May 2016 April/May 2016 | LIGHTING MAGAZINE 15 NICK JONES Energy Manager, UNSW Australia Tell me about your work. I’m the Energy Manager here at UNSW and my team look after all elements associated with utility use. What sort of role do LEDs play in your work? Lighting accounts for somewhere between 15 to 17 per cent of the use of electrical energy on the site, so any opportunity to reduce that is something I’d take. Now, as we know, LEDs are pretty energy efficient, so where we can we install those to replace fittings that are not so energy efficient. Sometimes we also use LEDs for feature lighting as well, or we put them in places where maintenance is challenging, such as high, inaccessible areas, because we generally get a good lifespan out of them. I suspect in the future that we will largely be LED. Already, for our newest buildings, LEDs are starting to become more prevalent in terms of the design proposals that we’re getting from the consultants. Tell me about current LED installations on the UNSW campus. We’ve recently refitted some of our teaching spaces and office spaces with LEDs. At this stage, we’re only just starting to get confident with the technology that’s being offered by the manufacturers. My personal experience is that some of the earlier offerings didn’t quite measure up to the salesperson’s claims in terms of longevity, stability, light output or colour rendering. How do today’s offerings compare? They’re better, mainly because the mainstream suppliers such as Philips and Osram have LED major mainstream lighting companies offering guarantees, we’re a bit more confident with that, but we have upwards of 25,000 fittings on the campus, so it could be a disaster if we’re not very careful about what we choose and the guarantee that we get with them. Colour rendering has also been an issue in the past. What are your thoughts on it now? I think the technology on the colour rendering is loads better than it was. I mean, we have some older LED lights that have got a definite blue tinge to them as they age. But even with the newer LEDs, whilst they offer up to 50,000 hours, I’m not sure fittings have been around that long to actually test the impact on their colour rendering capabilities in practice. We just have to wait and see if those capabilities are maintained over the life of the fitting. Do you have any data on energy efficiency and the cost savings of LEDs? We’ve done some trials. Generally, at the moment, the criteria we apply is the lumen Earlier version LEDs are still proving problematic when it comes to consistency of colour. Five-year-old LED downlights installed at UNSW show a blue discolouration. Image courtesy of UNSW. offerings. They’ve got a track record, so we’re a bit more confident in using their LED products at the university. What are some of the challenges you face in using LEDs? Whilst we know LEDs have good energy use specs, what we’re still a bit nervous about at the moment is replacement cost. Now, if a fluorescent tube fails, it costs three or four dollars to replace. If an LED fitting fails, you could be looking at a hundred dollars to replace it, so that is a concern we have at the moment. Nowadays with the efficiency per watt, so these days we’d be looking at something over 100, maybe 110 lumens per watt output. And obviously the CRI, I think over 80 is what we’re looking for. So what we were finding about 18 months ago was that the efficiency was actually similar to a very high efficiency fluorescent tube. Now, on a comparative basis in terms of efficiency, they’re starting to get the edge over high efficiency fluorescents. Apart from lifespan and energy savings, what other benefits do LEDs offer? They take load off the HVAC now they’re starting to run cooler than they used to. The early fittings had massive heat sinks on them, which wasn’t too good. These days I think that problem has largely gone away. The other thing I notice now is that some of the fittings we’re seeing have modular LED strips in, which in theory should make the ongoing maintenance of them easier and cheaper, but we haven’t really tested that yet to see how easy they are to replace. UNSW is increasingly installing LEDs to save energy and reduce maintenance costs. Here, strip LED and downlights are installed in the corridor and teaching rooms of Building L5 of the university’s Kensington campus. Image courtesy of UNSW.
Lighting February 2016 - Vol 36 Issue 1
Lighting June 2016 - Vol 36 Issue 3