HVAC Plant Finds Reasons to Replace Fluorescents with LEDs
OYL Manufacturing Company Sdn Bhd & J&E Hall is one of the top manufacturers of heating, ventilation and air conditioning (HVAC) units in Malaysia. It is a member of the Daikin group, which produces models under the Acson, York, American Air Filters, J&E Hull, McQuay and Daikin product brands for use in residential, commercial and industrial applications.
OYL/Daikin has a strong commitment to environment performance of their products. The units themselves are large consumers of end use electrical power. The company has taken numerous steps to minimize their products use of energy including using inverter compressors, more efficient heat exchangers and automatic filter cleaning. These product changes have allowed OYL/Daikin to reduce the average energy consumption of their units under JIS conditions by 32% over the past 15 years.
Not content with only optimizing the energy consumption of their end products, OYL also places a strong focus on sustainable manufacturing. OYL has a sustainability team which continuously reviews their operations and identifies opportunity areas where the plant’s impact on the environment can be reduced. The site has executed many sustainable manufacturing projects at the plant with simple payback periods from 2.5 months to over three years, including:
- Installation of air curtains at doorways: 9.4 months
- Inverter on air handling blower at canteen: 2.3 years
- Inverter on cooling tower fans: 1.5 years
- Utilities auto switch-off during non-operating periods: 3.7 months
- Local air blowers to switch off main air compressor during low demand: 7 months
- Rain water harvesting for process water and toilets: 3.1 years
- High Bay metal halide to induction lamp retrofit and noncritical over lighting removal: 2.1 years
- Fluorescent tube T8 to T5 retrofit and noncritical over lighting removal: 1.6 years
Even though the plant changed a portion of their fluorescent T8 tubes to T5, they still had more than 2,000 T8 x 1200 mm fluorescent tubes in the plant. These remaining T8 fluorescent tubes were identified by the sustainability team as an opportunity to reduce energy consumption further. Most of the tubes were located in people-centric areas such as in the offices, conference rooms, canteen, etc. Maintaining the lighting levels and lighting quality were identified as an important aspect during this retrofit project.
The sustainability and electrical team evaluated two options for the retrofit, changing to T5 fluorescent tubes (copy the previous fluorescent lighting retrofit project) and changing to T8 LED tubes. The team decided to implement the LED tubes for the following reasons:
- LED tubes have larger energy savings than corresponding T5 tubes. One of the reasons the previous T8 to T5 retrofit had such a short payback time is that many of the original T8 tubes were not replaced but removed for delamping. This was not possible with this retrofit.
- LED tubes have no harmful substances (RoHS certified) while T5 tubes contain mercury and are classified as a scheduled waste.
- LED tubes are of sturdy aluminum/polycarbonate construction while T5 tubes are made of glass and subject to breakage.
The project was assisted by Osprey Engineering. To minimize project investment, OYL in-house technicians installed the LED tubes over a three-month period. During the installation, the ballast and starter were bypassed with the line and neutral wired directly to the bi-pin sockets. The old fluorescent tubes were sent to a managed disposal company.
The main success criteria for this energy saving project are the delivery of equivalent or better lighting quality than the existing fluorescent tubes and realization of significant energy savings.
Lighting quality: A detailed lighting level study was done in the workshop office area of the plant. For this study, the lighting levels at the desk top height (1,800mm below the luminaire height) with the existing fluorescent tubes were compared with the new LED tubes. The measurements show that the lighting levels produced by the LED tubes averaged 27% higher than the fluorescent tubes.
Project savings: The energy consumption of a lighting circuit with eight luminaires (16 tubes) was analyzed before and after the retrofit. It was found that the LED tubes used only half of the power as the existing fluorescent tubes, 18.3 W vs. 35.3 W. The project financials show an annual savings of over RM 53,000 (about US $17,000) due to energy savings and lower maintenance cost due to longer lamp life. This savings occurs with a higher delivered illuminance. At current electric rates, the project payback is 4.7 years. Additional savings are expected when Malaysia rationalizes the current energy subsidies, which will substantially increase the electric rates.
For more details about the project and T-8 LED tubes, read the full case history, “Solid State Lighting: A Manufacturer’s Approach to Sustainable Operations.”