PUB pushes the boundaries of water technology

PUB, Singapore’s national water agency, has been able to give the country a robust, clean and sustainable water supply over the decades due to its strong commitment to research, technology and innovation. With a belief in nurturing continuous innovation for the long run, PUB aims to further harness research and development (R&D) to meet future water demand at today’s energy and sludge footprint.

It has set long-term targets to drive the next phase of innovation, namely to reduce energy used in desalination by more than two-thirds, increase NEWater recovery to 90 per cent at low energy levels, and make used water treatment fully energy self-sufficient while having sludge generation. It has also identified several promising technologies which will contribute towards reaching each of these targets.


Present challenges

R&D has been key to Singapore achieving a robust and sustainable water supply. The island-nation’s unique environment – which combines limited natural water resources and land to collect rain with the vagaries of dry weather – requires innovative solutions.

NEWater and desalinated water were made possible by technological breakthroughs following decades of R&D effort to short-circuit the natural water cycle so as to make water supply more weather-resilient. Together, they meet up to 70 per cent of today’s water demand and will make up to 85 per cent in 2060.

The challenges PUB faces in producing potable water vary with the type of source water used. While seawater and used water streams offer a potentially inexhaustible supply of water, the current desalination energy requirement and NEWater recovery rate pose the greatest barriers to their sustainable use.

These unconventional sources require between five and 17 times more energy to produce as compared to the conventional treatment of rainwater. Additionally, producing treated used water – before it is channelled to NEWater production – generates sludge which is costly to dispose of.

Meeting future water demand with today’s technologies will see PUB’s energy footprint quadruple from the current 1,000GWh/year to 4,000GWh/year, and the amount of sludge generated would also double from the current 300,000 tonnes/year to more than 600,000 tonnes/year by 2060. This is unsustainable and can only be overcome by leveraging on technological innovations.


Innovating for the future

Since 2002, PUB, together with research partners and the National Research Foundation have invested S$453 million in over 600 water R&D projects in collaboration with partners from 27 countries. These projects span across the technology readiness spectrum, from basic research to lab-scale prototypes, pilot studies and demonstration plants before full-scale deployment and commercialisation.

“R&D is the process of looking for solutions today to solve problems of the future. As we become increasingly reliant on desalination and water reuse, the challenge is to ensure that technological advancements continue to keep up with increasing water demand so that these sources remain sustainable,” said Mr harry Seah, PUB’s Assistant Chief Executive (Future Systems and Technology). “PUB is pushing the frontier of water technology to tackle the pressing challenges in energy and sludge management efficiency and is on track to meet its long-term targets. The key to this is collaboration with the local and global research community to develop real, applicable solutions to keep water supply secure and affordable.”

These technologies will be showcased at the TechXchange and Water Innovation Pavilion at the Singapore International Water Week 2018.