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Proposed changes to MEES for water-cooled chilled water systems used for space cooling in new industrial facilities
The National Environmental Agency (NEA) is seeking feedback on the proposed changes to the Minimum Energy Efficiency Standard (MEES) for Water-Cooled Chilled Water systems (WC-CWS) used for space cooling in New Industrial Facilities.
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National Environment Agency
Consultation Period: 31 Dec 2024 - 31 Jan 2025
Status: Closed - Summary of Responses
Consultation Outcome
NEA’s Response to Feedback Received from the Public Consultation on Proposed changes to Minimum Energy Efficiency Standards for Water-cooled Chilled Water Systems used for Space Cooling in New Industrial Facilities
The National Environment Agency (NEA) has concluded its public consultation on the proposed changes to Minimum Energy Efficiency Standards (MEES) for water-cooled chilled water systems (WC-CWS) used for space cooling in new industrial facilities (NIF).
NEA received feedback from 6 respondents through this consultation exercise. Overall, respondents were supportive of the proposed changes, with some providing their suggestions and feedback on the proposed changes. NEA’s response to the feedback is summarised in the table below.
Feedback received and NEA’s response
Key Feedback | NEA’s Response |
WC-CWS used for space cooling in production areas (e.g. clean rooms) of pharmaceutical, electronics, and semiconductor companies would require chilled water supply of low temperature to reduce the relative humidity of the air supply. | 1. The proposed MEES level will be adjusted by 0.01kW/RT for every 1°C reduction in chilled water supply temperatures (CHWST) from 7°C, This will address the industry’s feedback that NIFs may need to operate their WC-CWS at low CHWST to meet specific requirements of their production spaces or client's cooling requirements, while aligning with BCA’s standards for new commercial buildings. Refer to Annex: Proposed MEES level. 2. There are proven, energy efficient and cost-effective equipment such as desiccant dehumidifiers to control relative humidity without the need to operate the WC-CWS at low CHWST. 3. The proposed MEES level applies only to NIFs that apply for planning permission or equivalent from 1 Apr 2026. 4. NIFs will have ample lead time to include such equipment in their design / planning phase to ensure that they are able to meet the MEES. 5. NIFs can tap on EDB’s Resource Efficiency Grant for Emissions (REG-E) to defray CAPEX before 1 Apr 2026. After 1 Apr 2026, REG-E will support WC-CWS that exceed the performance stipulated by MEES. |
District Cooling Systems (DCS) may have to operate their existing WC-CWS at very low chilled water supply temperature to meet regulatory requirements under the District Cooling Act or client requirements. |
NEA would like to thank all stakeholders who participated in the consultation exercise. We look forward to your active participation again in future public consultations.
Annex: Proposed MEES level
CHWST (°C) | 3 | 4 | 5 | 6 | 7 and above |
MEES (kW/RT) | 0.67 | 0.66 | 0.65 | 0.64 | 0.63 |
Remarks | The MEES level will be adjusted by 0.01kW/RT for every 1°C reduction in CHWST. | Aligned with BCA’s 0.63kW/RT WC-CWS standard for new commercial buildings which typically operate at CHWST of 7 °C for space cooling. |
Detailed Description
Aim
The National Environmental Agency (NEA) is seeking feedback on the proposed changes to the Minimum Energy Efficiency Standard (MEES) for Water-Cooled Chilled Water systems (WC-CWS) used for space cooling in New Industrial Facilities. The consultation will commence on 31 Dec 2024 and end on 31 Jan 2025.
Background
NEA introduced MEES for WC-CWS in new industrial facilities in 2020 to set a benchmark for the industry and catalyse companies to adopt, develop and operate more energy efficient systems. This is part of our initiative to reduce Singapore’s greenhouse gas emissions, where the industrial sector accounts for the largest share of the emissions and has the largest potential for reduction.
Under the Energy Conservation Act (ECA), new industrial facilities that apply for planning permission or equivalent on or after 1 Dec 2020 must conform to MEES for water-cooled chilled water systems. 1 Refer to the table below for the tiered-MEES based on the chilled water supply temperature.
Tiered-MEES based on the chilled water supply temperature
Chilled water supply temperature (˚C) | 3 | 4 | 5 | 6 | 7 | 8 | 9 | ≥10 |
MEES in kWe/kWc (kW/RT) | 0.203 (0.714) | 0.200 (0.703) | 0.197 (0.693) | 0.194 (0.682) | 0.191 (0.672) | 0.188 (0.661) | 0.185 (0.651) | Energy performance for chilled water supply temperature ≥10 oC to be improved from 0.185 kWe/kWc at 9oC by 0.003 kWe/kWc for every 1°C increase in chilled water supply temperature |
Existing industrial facilities with WC-CWS will be required to conform to the same MEES when MEES for WC-CWS is implemented for registered corporations under the ECA on 1 Dec 2025 and other industrial facilities on 1 Dec 2029.
Proposed Alignment
Under BCA’s Building Control (Environmental Sustainability) Regulations, WC-CWS used in new commercial buildings for space cooling must meet a minimum energy efficiency standard of 0.63kW/RT as specified under the Code for Environmental Sustainability of Buildings (4th Edition)2.
NEA intends to align the MEES level for WC-CWS that is dedicated only for space cooling3 purposes with BCA’s energy efficiency standard. The new requirement will be as follows:
New industrial facilities that are applying for planning permission or equivalent on or after 1 Apr 2026 that install WC-CWS only for space cooling purposes will need to comply with a single MEES level of 0.63kW/RT (0.179kWe/kWc) regardless of the chilled water supply temperature.
WC-CWS that are used for process cooling including for multiple applications (space and process cooling) will still be subject to the tiered-MEES to cater to the wide range of chilled water temperatures required (see Para 3).
The alignment will improve consistency of WC-CWS standards cross government agencies and further improve the energy performance of WC-CWS in new industrial facilities. NEA intends to gazette this legislative amendment by November 2025 and to implement the alignment from 1 Apr 2026.
Request for Feedback
This proposal is released for the purpose of consultation. All comments received during the consultation exercise will be reviewed and will be taken into consideration in developing the final requirements. Parties wishing to provide feedback may do so at go.gov.sg/mees. The consultation exercise will end on 31 Jan 2025.
1 MEES cover electrically driven, water-cooled chilled water systems in industrial facilities with a total installed capacity of 1055kW (300RT) or more, which produces chilled eater at a temperature of 3oC or higher.
2 The Building Control (Environment Sustainability) Regulations apply to building works which involve gross floor area of 5,000 m2 or more. The minimum energy efficiency standards specified for water-cooled chilled water plants in the Code of Environmental Sustainability of Buildings (4th Edition) apply to building cooling systems that serves an aggregate air-conditioning area of more than 500m2. Chilled water systems in commercial buildings are mainly used for space cooling.
3 Space cooling includes but is not limited to the cooling of spaces such as office areas, clean rooms, storage rooms.