Energy reduction is a great challenge in road lighting applications. Replacing high-pressure sodium vapor (HPSV) with light-emitting diodes (LED) is a viable approach to reducing energy consumption. However, a total replacement can incur a significant capital cost. This study aims to investigate the effects on light distribution by replacing HPSV lamps with LED lamps in HPSV luminaires using Light Intensity Distribution (LID) curve measurement and Backlight, Uplight and Glare (BUG) rating evaluation to reduce the adoption costs. While LED lamps have high illumination rates, the structural differences from HPSV lamps can affect the LID curve and original lighting design. Therefore, it is crucial to study photometric dispersion after retrofitting light sources. Both lamps were installed into similar HPSV luminaires to assess photometric performance using goniophotometer measurements. The HPSV lamp outperforms the LED lamp in terms of luminous flux (11.13%) and light intensity (7.69%), whereas the LED lamp outperforms the HPSV lamp in terms of efficacy rating (68.67%) and wattage used (47.61%). The findings indicate that retrofit LED luminaires have an LOR of 46.77% lower than the HPSV luminaires. The light distribution pattern is maintained but reduced to 40 to 50% for the main usable light angles. The reduced performance is caused by the lamp structure, which occupies a large area inside the luminaire housing, obstructing proper light distribution. Although overall energy consumption is reduced, similar illumination levels cannot be maintained. These outcomes can assist authorities and manufacturers with alternative methods of reducing costs while maintaining lighting levels.

• Abdullah, A., Aziz, M., & Huda, M. (2021). Redesigning public street lighting using photometric method. Indonesian Journal of Computing, Engineering and Design (IJoCED), 3(1), 54–67. https://doi.org/10.35806/ijoced.v3i1.153

• Bamisile, O. O., Dagbasi, M., & Abbasoglu, S. (2016). Economic feasibility of replacing sodium vapor and high pressure mercury vapor bulbs with LEDs for street lighting. Energy and Policy Research, 3(1), 27–31. https://doi.org/10.1080/23815639.2016.1201442

• Bergen, A. S. J. (2012). A practical method of comparing luminous intensity distributions. Lighting Research & Technology, 44(1), 27-36. https://doi.org/10.1177/1477153511435769

• BERNAMA. (2023). 212,639 Street Bulbs Replaced with LED Lights - TNB. Bernama Energy.com. http://energy.bernama.com/news.php?id=1737759

• Bhattacharya, S., Majumder, S., & Roy, S. (2023). Modelling of the effects of luminaire installation geometries and other factors on road illumination system photometric parameters and energy efficiency. World Journal of Engineering. https://doi.org/10.1108/WJE-09-2022-0372

• Braga, M. F., Nogueira, F. J., Campos, M. F. C., Gouveia, L. H. B., & Braga, H. A. C. (2014). A comparative study regarding linear fluorescent and LED lamps for indoor lighting. [Paper presentation]. 11th IEEE/IAS International Conference on Industry Applications, Juiz de Fora, Brazil. https://doi.org/10.1109/INDUSCON.2014.7059469

• Bredemeier, K. (2017). Photometric Data for the Development of Lighting Components. Universitätsbibliothek Ilmenau.

• British Standard. (2015). BS-EN 13201-2 Road Lighting: Performance Requirements. BSI Standards Publication

• Brons, J. A., Bullough, J. D., & Frering, D. C. (2021). Rational basis for light emitting diode street lighting retrofit luminaire selection. Transportation Research Record, 2675(9), 634-638. https://doi.org/10.1177/03611981211003890

• Chinnis, D., Mutmansky, M., & Clanton, N. (2011). IES TM-15 BUG value-setting and adjustment methodology. Leukos, 8(1), 25-39. https://doi.org/10.1080/15502724.2011.10732155

• Czyżewski, D. (2023). The photometric test distance in luminance measurement of light-emitting diodes in road lighting. Energies, 16(3), Article 1199. https://doi.org/10.3390/en16031199

• Gordic, D., Vukasinovic, V., Kovacevic, Z., Josijevic, M., & Zivkovic, D. (2021). Assessing the techno-economic effects of replacing energy-inefficient street lighting with LED corn bulbs. Energies, 14(13), Article 3755. https://doi.org/10.3390/en14133755

• Grau, F., Cervantes, J., Vázquez, L., & Nuñez, J. R. (2021). Effect of LED technology on technical losses in public lighting circuits. A case study. Journal of Engineering Science and Technology Review, 14(2), 198–206. https://doi.org/10.25103/jestr.142.24

• International Commission on Illumination. (1996). CIE 121 1996: The Photometry and Goniophotometry of Luminaires. International Commission on Illumination.

• Jabatan Kerja Raya. (2018). Garis Panduan Penggunaan Lampu Jalan Jenis Cekap Tenaga untuk Pemasangan Baharu dan Sedia Ada Projek Kerajaan (CKE.GP.01.54.(00).2018) [Guidelines for the Use of Energy-Efficient Road lighting for New and Existing Installations for Government Projects (CKE.GP.01.54.(00).2018)]. Jabatan Kerja Raya. https://dokumen.tips/documents/garis-panduan-penggunaan-lampu-jalan-jenis-cekap-epsmgjkrgovmyimages669garispanduanlampujalancekaptenaga.html?page=2

• Kovačević, Z., Vukašinović, V., & Gordić, D. (2022). Piecewise techno-economic analysis of led corn bulbs for street lighting. Applied Engineering Letters, 7(2), 74–80. https://doi.org/10.18485/aeletters.2022.7.2.4

• Lewotsky, K. (2011, November 22). Understanding and Preventing LED Failure. DigiKey. https://www.digikey.com/en/articles/techzone/2011/nov/understanding-and-preventing-led-failure

• Li, Q., Wang, Z., Kolla, R. D. T. N., Li, M., Yang, R., Lin, P. S., & Li, X. (2023). Modeling effects of roadway lighting photometric criteria on nighttime pedestrian crashes on roadway segments. Journal of Safety Research, 86, 253-261. https://doi.org/10.1016/J.JSR.2023.07.004

• Philips. (2023). The Best LED Replacement for HID and SON Road Lamps with TrueForce LED TrueForce LED Public (Road-SON). Philips. https://www.lighting.philips.co.uk/api/assets/v1/file/PhilipsLighting/content/comf7165342-pss-en_gb/LP_CF_7165342_EU.en_GB.PROF.CF.pdf

• Rofaie, N. S. A., Phoong, S. W., & Mutalib, M. A. T. A. (2022). Light-emitting diode (LED) versus high-pressure sodium vapour (HPSV) efficiency: A data envelopment analysis approach with undesirable output. Energies, 15(13), Article 4589. https://doi.org/10.3390/en15134589

• Rofaie, N. S. A., Phoong, S. W., & Mutalib, M. A. T. A. (2022). Light-emitting diode (LED) versus high-pressure sodium vapour (HPSV) efficiency: A data envelopment analysis approach with undesirable output. Energies, 15(13), Article 4589. https://doi.org/10.3390/en15134589

• Setyaningsih, E., & Candra, H. (2023). Optimization of photometric quantities for road lighting freeways in Indonesia. Journal of Theoretical and Applied Information Technology, 31(6), 2433-2441.

• TEEAM. (2012). The Electrical and Electronics Association of Malaysia [Technical report]. https://www.scribd.com/document/707493031/Technical-Report-Suitability-of-LED-for-Road-Lighting-in-Malaysia-Manualzz

• Ying, J. K. X., & Lim, W. F. (2022). Study and optimization of lens shape affecting light patterns of light-emitting surface based LED street lighting. Optik, 260, Article 169083. https://doi.org/10.1016/j.ijleo.2022.169083

• Yousif, O. S., Majid, M. Z. A., Aminudin, E., Zakaria, R., Wahid, C. M. F. H. C., Neardey, M., & Ramli, M. R. (2018, October 24-26). Energy and economic benefits of LED adoption in Malaysia highway lighting system. [Paper presentation]. Proceedings of the 4th International Conference on Low Carbon Asia, Johor Bahru, Malaysia.

• Zima, K., & Ciepłucha, W. (2023). Efficiency analysis of roadway lighting replacement in a selected polish municipality. Applied Sciences, 13(5), Article 3257. https://doi.org/10.3390/app13053257