Improvability of Thai’s Building Energy Code via Lighting Power Density Requirements

Main Article Content

Nichakorn Hengrasmee Sant Chansomsak


The Thai government plans to enforce the Thai’s new Building Energy Code or BEC, which is a Ministerial Regulation in 2009 for the building to be submitted for construction or modification and it has been in forced since mid of this 2018. In order to achieve its 20-year reduction of energy intensity used in accordance with the National Energy Conservation Plan 2015-2022. BEC has been promulgated for 9 years and it has not been updated to reach the minimum standards in line with the current technology. Specifically, the lighting criteria for energy efficiency in building. Consequently, the Lighting Power Density allowance per square meter or LPD is set based on lighting technology on that day. Therefore, in order to meet the government targets, BEC should reconsider the criteria for defining the new LPD to match with current technology to increase the energy efficiency of buildings. This article illustrates the concepts used in configuring the new LPD, to be consistent with today's technology. The case study was designed to determine the brightness level according to Ministerial Regulation no.39 and to compare the LPD values from three types of lamps, which represents the current lighting technology. The results of this study is not only showing the relationship between the thresholds for defining LPD according to BEC and the brightness level in accordance with the Ministerial Regulations but also shows how much the standard of LPD can be achieved. With today's lighting technology, the lighting power density of T8 fluorescent lamp, which has the lowest energy efficiency compared to the others in the case study, is still lower than the minimum energy efficiency standard of 19% and can be reduced up to 31% with the advantages of LED technology. Reducing LPD value will be the key to develope the benchmark and increase the energy efficiency of the buildings in the future.


Article Details



1. ASHRAE. (2013). ANSI/ASHRAE/IES Standard 90.1-2013 (Vol. 90.1-2013). United States.
2. Chindavanig, Thanit. (2003). Building energy with National Economic Development Plan. [พลังงานในอาคารกับแผนพัฒนาเศรษฐกิจและสังคมแห่งชาติ]. Engineering
Today, 1(03).
3. EPPO. (2015). Thailand 20-Year Energy Efficiency Development Plan (2015-2036). Ministry of Energy.
4. Gazette, Royal Thai Government. (1994). Ministerial Regulation No. 39 (B.E. 2537) issued by virtue of the Building Control Act, B.E. 2522. The Government
Gazette: the Minister of Interior.
5. Gazette, Royal Thai Government. (1995). Royal decree on designated buildings B.E. 2538.
6. Gazette, Royal Thai Government. (2000). Ministerial Regulation No.55.
7. Gazette, Royal Thai Government. (2007). Ministry of education on the standardization of private schools, general education pre-primary primary school and high 8. school. The Government Gazette.
9. Gazette, Royal Thai Government. (2009). Ministerial Regulation Prescribing Type or Size of Building and Standard, Criteria and Procedure in Designing Building
for Energy Conservation B.E. 2552.
10. GmbH, DIAL. (2016, 15 June 2016). Efficiency of LEDs: The highest luminous efficacy of a white LED. Retrieved 20 November 2018, 2018, from
11. IESNA. (2011). The Lighting Handbook: Tenth Edition, Reference and Application (10). USA: Illuminating Engineering Society.
12. Philips. (2013). Philips creates the world’s most energy-efficient warm white LED lamp [Press release]. Retrieved from
13. Praiwan, Yuthana. (2018, February, 9). New energy code for large buildings, Some structures must meet standard in 2018. Bangkok Post. Retrieved from
14. Thai-German Programms on Energy Efficiency Development Plan (TGP-EEDP), Coordinating Center for Energy Conservation Building Design (2E building
Center). (2016). Architectural guide book. bangkok: Department of Alternative Energy Development and efficiency, Ministry of energy.
15. Toomwongsa, Niratsai. (2018, April). Thailand industry outlook 2018-20. Construction contractor. Retrieved from