Singapore studying feasibility of building sixth water desalination plant

Key Concepts

• Desalination: The process of removing salts and minerals from seawater to produce potable water.
• PUB: Singapore’s National Water Agency.
• NEWater: High-grade reclaimed water produced from treated used water.
• Energy Intensity (of Desalination): Measured in kilowatt-hours per cubic meter of water produced.
• Water Demand Forecast: Projected increase in water usage in Singapore, particularly by 2065.

Sixth Desalination Plant Feasibility Study

Singapore’s PUB (the National Water Agency) has issued a tender for a feasibility study regarding the construction of a sixth desalination plant. The study, anticipated to last approximately 10 months, will focus on determining the viability of a plant capable of treating both seawater and freshwater sources. A key consideration outlined in the tender documents is the potential for a fully underground facility. This design choice is motivated by the desire to maximize land use, allowing the surface area to be allocated to other infrastructure projects or recreational spaces.

Potential Location and Energy Efficiency Improvements

An industry source suggests a potential location for the plant in southwest Singapore, strategically positioned to better serve industrial demands in that region. Beyond location, the study will also assess the technical and economic feasibility of various plant designs, with a particular emphasis on improving energy efficiency. Currently, desalination processes in Singapore consume approximately 2.5 to 3.5 kilowatt-hours (kWh) per hour. The industry expert stated, “I think you're looking at uh very very detailed uh systems and technologies to improve uh the energy consumption. I mean right now you're looking at about you know 2.5 to 3.5 kilowatt per hour. I think any one that can bring this down by 20 30% that would be a gamecher.” A reduction of 20-30% in energy consumption would represent a significant advancement.

Singapore’s Water Sources and Increasing Demand

Singapore currently relies on a diversified water supply portfolio. This includes rainwater harvested from reservoirs and canals, imported water from Malaysia, NEWater (reclaimed water), and desalinated water. Desalination became the nation’s fourth “national tap” in 2005. Currently, five desalination plants operate across the island: three in Tuas (western Singapore), and two in Marina East and Jurong Island.

The need for increased water supply is driven by a substantial projected increase in demand. Singapore currently uses enough water daily to fill 800 Olympic-sized swimming pools. Demand is forecast to nearly double by 2065, necessitating proactive measures to ensure water security.

Desalination Process and NEWater Explained

Desalination is described as an “energy-intensive process” involving the removal of salts and minerals from seawater to produce drinking water. Complementing desalination is NEWater, defined as “a highgrade reclaimed water” resulting from the “treatment and purification of used water.” Both technologies are crucial components of Singapore’s long-term water strategy.

Synthesis

The feasibility study for a sixth desalination plant underscores Singapore’s commitment to bolstering its water resilience in the face of growing demand. The focus on both freshwater/seawater treatment capability and underground construction, coupled with a strong emphasis on energy efficiency, demonstrates a forward-thinking approach to water management. The diversification of water sources – including desalination, NEWater, rainwater harvesting, and imported water – remains a cornerstone of Singapore’s strategy to secure a sustainable water supply for the future.