- Today, more than 200 water heater models have been registered under NEA’s expanded Mandatory Energy Labelling Scheme (MELS) which came into force on 1 April 2025. Over 75% of certified gas water heaters are rated 4 out of 5 ticks while just 2 in 68 (3%) electric storage models meets the same benchmark.
- Water heaters are the third-largest household energy guzzler, after air-conditioners and refrigerators, accounting for 10% of energy use. From April 2026, models that fail to meet at least a one-tick energy rating under NEA’s labelling scheme can no longer be sold.
- A study on water heaters found that in Singapore, electric storage models produce about 400 kg of carbon emissions per user annually, compared to just 80 kg from gas instant water heaters.
- City Energy also observed growing uptake among condo developers over the past 3 years, with 70% of new development dwelling units with town gas connections opting to install gas water heaters.
Singapore, 5 November 2025 – The National Environment Agency (NEA) extended the Mandatory Energy Labelling Scheme (MELS) to household water heaters on 1 April 2025, adding them to the list of regulated appliances such as refrigerators, air-conditioners, and clothes dryers. This move is part of ongoing sustainability efforts to make households more energy efficient.
Since then, more than 200 water heater models have been registered and rated from one to five ticks for energy efficiency. These include gas instantaneous, electric instantaneous, and electric storage models. To date, the highest rating achieved among the 3 models is four ticks, with 16 out of 21 gas instantaneous heaters reaching this benchmark, compared to just 2 out of 68 electric storage models.
A higher tick rating indicates more hot water produced for every kilowatt-hour (kWh) of energy consumed. By switching from a 1-tick electric storage to a 4-tick gas instant model, households can save up to $1,200 over the gas water heater’s lifespan based on a study by NEA1. The calculation assumes three showers a day per household. Families who use more hot water may enjoy even greater savings, and possibly more if their current heater falls below the 1-tick efficiency benchmark.
A research study2 by Associate Professor Lee Siew Eang, Honorary Fellow, Department of the Built Environment, College of Design and Engineering, National University of Singapore (NUS), indicates that gas water heaters emit about 0.1913 kg of CO₂ per kWh, compared to 0.4085 kg for electric water heaters.
The higher emissions from electric storage water heaters stem from the fact that electricity must first be generated, mainly by burning natural gas3 in Singapore. In contrast, town gas can be used directly for heating, without the extra conversion step that causes additional energy loss and emissions.
On top of emitting nearly twice the carbon per unit of energy, electric storage heaters are also less energy efficient, as they experience higher standby losses from keeping large volumes of water heated over extended periods.
Each year, electric storage water heaters are estimated to emit about 400 kg of carbon per user, five times more than gas instant models at 80 kg. Switching to gas could therefore cut emissions by up to an estimated 320 kg annually per user.
If every household in Singapore uses an electric storage water heater and collectively switches from using electric storage water heaters to gas instant water heaters, we could offset carbon emissions equal to planting about 1.4 million trees or removing more than 300,000 cars from the road annually.
Over 210,000 homes in Singapore use gas water heaters
City Energy, Singapore’s sole provider of piped town gas, observed growing uptake among condominium developers in the past 3 years, with 70% of newly built private homes with town gas connections opting to install gas water heaters.
Nationwide, gas water heaters are now used in more than 210,000 households to date representing roughly 14.3% percent of all homes in Singapore. Across completed projects, installations are up about 210% in 2023–2025 versus 2020–2022, driven by stronger efficiency messaging, updated designs, and the promise of on-demand hot water.
Soh Guan Hong, Senior Vice President, Residential Sales Group Head, City Energy said: “As households become more conscious of their energy use and taking an active role in choosing lower-carbon choices, we expect City Energy to play an even bigger role in Singapore’s sustainability journey starting with raising awareness of gas water heaters. With NEA’s labelling scheme raising awareness, more families and developers are now prioritising efficient appliances. We will continue working to make gas water heating even more accessible for modern homes.”
Koon Wai Leong, General Manager, Hoi Hup Pte Ltd said: “In planning new developments, we look closely at what adds long-term value for homeowners. Gas water heaters stand out because they are more energy efficient, and space-saving. With the national labelling scheme now in place, we see more buyers asking for appliances that meet higher energy standards. Installing gas water heaters gives our projects an edge, while also aligning with Singapore’s broader sustainability goals. It’s a choice that benefits both residents and the environment.”
Tony Wong, homeowner at The Waterview Condo, said: “For us, choosing a gas water heater was about ease of maintenance, comfort and conscience. We liked that it heats water quickly without wasting energy, which keeps our bills down and means we never run out of hot water, even with back-to-back showers. Knowing that it also reduces our household carbon footprint is just icing on the cake. It feels good to know that our daily routines can be both convenient and environmentally responsible.”
Why more households are choosing gas water heaters
Unlike electric storage models, which must reheat an entire tank of water to about 60°C each time before use, a requirement not just for user comfort but also to prevent bacteria such as Legionella from growing in the tank, gas water heaters only heat the water that is needed at the moment of use.
Other benefits of gas water heaters include:
Energy and Cost Efficiency
- Operate on demand, helping households avoid wasted energy and lower their utility bills, especially amid rising electricity tariffs.
Convenience and Comfort
- Deliver hot water instantly with no waiting time.
- Provide consistent temperatures even during back-to-back showers.
- Offer strong flow rates suitable for rain showers and multi-point usage.
Space-Saving Design
- Tankless and wall-mounted design frees up space in bathrooms and service yards.
- Ideal for space-conscious households in BTO flats, condominiums, and apartments.
Life by City Energy Gas Water Heaters
City Energy also launched its own brand of gas water heaters currently available only to HDB homeowners. Through smart home integration with the iAppliances app, users have greater control over comfort and energy use.
Designed for service yard installation, Life by City Energy Gas Water Heaters are compact yet stylish, with six colour options that complement modern interiors.
It eliminates the bulk and maintenance challenges of traditional storage tanks, which often occupy precious space or require concealment behind false ceilings.
Engineered with self-adaptation technology for stable water temperatures and whisper-quiet operation, Life by City Energy Gas Water Heaters also carry TÜV SÜD certification with 25 protective mechanisms to ensure peace of mind for families.
For households with multiple bathrooms, homeowners who value aesthetics and want to enjoy the ultimate rain showering experience, Life by City Energy Gas Water Heaters offers a solution that combines reliability, safety, and modern convenience.
1 https://www.nea.gov.sg/our-services/climate-change-energy-efficiency/energy-efficiency/household-sector/tips-on-buying-energy-efficient-appliances
2 From the Study On Domestic Water Heaters Energy Use And Its Climate Impact In Singapore – Page 51
3 From https://www.sg101.gov.sg/environment/case-studies/energy/