Energy Savers: Cynthia Jolley Rogers, Lighting Designer
We speak with Cynthia, Lighting Consultant, Projects & Advisory Division at Energy Action. Following 12 years in theatre and 10 years in the lamp replacement industry, Cynthia graduated in commercial lighting design with the Illuminating Engineers Society at RMIT.
Exergy Australia was bought out by Energy Action in March 2014. Cynthia's new role has a practical application in managing the Supply and Install side of the Energy Action machine.
How have client lighting design requests changed over the past 5 years in the commercial property sector?
The difference in lighting design requests varies depending on the customer's financial drivers. Commercial property owners are driven by NABERS, CBD Lighting and Green Star to achieve energy efficient lighting systems, because the better their NABERS or Green Star rating the more likely they will be able to lease their property to green conscious, high paying tenants. Industrial customers running warehouses or factories are far more pragmatic, and will only take action when the estimates indicate fast return on investment for their lighting upgrade. A projected payback of more than 3 years frequently results in no work being done.
How do you balance the competing demands of efficiency and light quality?
By very definition an efficient system is one that works well with a minimum of energy use. In order for the system to work well it needs to achieve certain targets. Recommended light levels, low glare and aesthetically pleasing environments are all essential targets. The system must first achieve those targets, and then it must do it with the least amount of energy use possible. A dark and gloomy office full of with depressed staff is not efficient, it is retrograde. The Exergy motto is to make buildings work, and that can be done efficiently if we are clever about it.
What new lighting technologies excite you & why?
Luminaires with inbuilt sensors are making lighting upgrades for back of house spaces quick and easy. Wireless technology is simplifying controls installations, and allowing clever grouping of those luminaires. LED produces great depth of colour, and that is great in the context of theatre. OLED is exciting. It is not likely to be a useful and affordable light source any time in the near future, but the organic shapes and endless possibilities of that technology are really intriguing.
What are your key design challenges with LED lighting & controls?
As everyone is aware, LED is
still an emerging technology with changes occurring in efficacy and life
at such a rate that there are new and better luminaires on the market
every month. For at least a year now LED down lights have been
outperforming CFL down lights in lumen output, distribution and price to
such an extent that you would no longer even consider using a CFL down
light anywhere. In the last few months LED has become equal to T5
linear fluorescent in output and distribution so that as the prices come
down we can start to consider LED troffers as a real option. In some
cases T8 linear fluorescent is still the best performer, but LED is
quickly catching up to even those.
The challenge with LED lighting is choosing a luminaire that is reliable and with good performance. Since LEDs are comparatively new in the market this cannot be done from long standing experience like with fluorescents. It can only be done through approvals and testing. When choosing any luminaire for commercial or industrial clients the designer must be careful to ensure that the luminaire meets Australian codes for electrical safety and EMC. Proof of these approvals must be able to be shown. Although it is very tempting to use a low budget luminaire to save capital cost and reduce payback time, it is crucial to ensure that the luminaire meets basic Australian electrical approvals. Next it is important to check that the claims made by the manufacturer about the luminaire’s performance can be backed up with tests, and that the tests have been performed by a reputable laboratory, not cooked up by the manufacturer themselves. A reputable laboratory is one that is approved by the International Laboratory Accreditation Corporation (ILAC). In Australia NATA is a signatory of ILAC, so any laboratory in Australia that is approved by NATA is reliable. In China CNAS is the ILAC signatory, so any reputable laboratory in China should have CNAS approval. If it doesn’t – don’t trust the test results.
I spend a proportion of my time researching and testing luminaries from suppliers. I request test results on products and conduct web searches on the laboratory the tests come from. I request copies of the electrical safety and EMC approval certificates, test results and the luminaire performance software files that are generated from those tests (ies files). I request samples to be brought to my office or I go to the manufacturers sites and run tests to ensure that the luminaires are using the energy they claim to use, and have a high power factor. If samples come to Canberra I put them in the ceiling and take light readings to compare the performance with other luminaires I have had in the same space. Testing, analysis and research are the means I apply to ensure I am using a quality product, and it can be challenging to keep up with all the latest developments.
With controls experience has taught me to keep controls as simple as possible to ensure that they are comissionable, and user friendly. The desired function of the controls much be carefully specified to ensure everyone on the project knows what is expected or required, including the client and the contractor. After the contractor has commissioned and tested the system , the designer needs to witness the system in action to ensure that it has been commissioned according to the specification. Any failure to achieve the agreed performance of the system then needs to be addressed as a defect during the defect period. It is also a good idea to specify a tuning period. This enables tweaking in the system if the occupants or client find that the specified performance is not working out as expected. Controls are so often rushed because they are installed right at the end of the project. Taking the time to address defects properly and address tuning issues after PC is the best way to achieve a controls system that works for energy efficiency, the client and the building occupants.
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