PUB to build world’s largest ocean-based CO2 removal demonstration plant in Tuas, Singapore

Rendering of an ocean-based CO2 removal plant (Image: Charles Grace, courtesy of Equatic)

Singapore’s National Water Agency PUB is collaborating with University of California (UCLA) and a startup spun out of research at UCLA — Equatic — to build a US$20m full-scale demonstration plant, following the launch and operation of two pilots in Los Angeles, US, and Singapore in 2023.

Over the next 18 months, the team of researchers from the UCLA Institute for Carbon Management (ICM) and Equatic will set out to build the world’s largest ocean-based carbon dioxide removal (CDR) plant at PUB R&D facility in Tuas, located in western Singapore.

When fully completed in 2025, the new plant — named Equatic-1 — will be equipped to remove 10 metric tonnes of CO2 per day from seawater and the atmosphere — 100 times more than the existing pilot. If successful, the technology would allow for the greenhouse gas (GHG) to be removed and stored, while producing nearly 300kg of carbon-negative hydrogen daily. At full scale, Equatic-1 can remove as much CO2 as what nearly 850 people emit annually. When this facility has fulfilled its technical demonstration objectives, Equatic will scale and commercialise the technology globally and launch commercial plants designed to remove nearly 110,000 metric tonnes of carbon dioxide per year — equivalent to the annual carbon emissions of more than 25,000 individuals.

ICM pilot plant facility in Singapore (Image: Satheesh Kumar Raman)

The demonstration plant will be co-funded by PUB, the National Research Foundation (NRF), Singapore, and UCLA ICM. Equatic’s existing plant in Singapore, piloted at 100kg of carbon dioxide removal per day, has proven successful. PUB has set a target to achieve net zero emissions by 2045. This collaboration with UCLA and Equatic is part of Singapore’s broader efforts to source for novel technologies, such as carbon capture, utilisation and storage (CCUS), which could contribute to mitigating the impacts of climate change.

“The pilot plant commissioned in Singapore provided performance data to substantiate our carbon dioxide-removal efficiencies, hydrogen-production rates and energy requirements for the process,” said Equatic co-founder Dante Simonetti, an associate professor of chemical and biomolecular engineering at UCLA Samueli and ICM’s associate director for technology translation. “The findings helped define the pathway for the design and engineering of Equatic-1 based on scaling performance confirmed by the pilot system.”

The Equatic process activates and expands the ocean’s natural ability to store CO2 by removing dissolved CO2 while enhancing the ocean’s capacity to absorb more of the GHG. Utilising electrolysis, an electrical current is passed through seawater brought in from the adjacent desalination plants operated by PUB. The process induces a series of chemical reactions that breaks water into its carbon-negative hydrogen and oxygen constituents while securely storing both dissolved, in sea water, and atmospheric CO2 in the form of solid calcium and magnesium-based materials for at least 10,000 years. The carbon credits from Equatic-1 are allocated to the project’s partners, and Equatic has entered into agreements with companies including Boeing for the purchase of carbon credits from future commercial plants.

Equatic-1 is also being built as a modular system, allowing the performance of individual units to be staged and stacked in preparation for systematic and rapid expansion. This approach reduces risks associated with scaling technology innovation. The system will also employ selective anodes, newly developed with the support of the US Department of Energy’s Advanced Research Projects Agency-Energy (ARPA-E), to produce oxygen while eliminating the unwanted byproduct of chlorine during seawater electrolysis. This opens a new pathway to CDR at the gigaton scale with the co-production of hydrogen — a clean fuel vital to decarbonising transportation and industrial applications – using seawater as a limitless input.

The technology has been named one of TIME’s Best Inventions of 2023 and listed among Popular Science’s 50 greatest innovations of 2023. It also won the 2021 Liveability Challenge, a global competition backed by Singapore-based non-profit Temasek Foundation with 450 applicants from more than 60 countries.

“We are pleased to further our collaboration with UCLA and Equatic, to develop a solution that has potential synergies with PUB’s desalination plants,” said Dr Pang Chee Meng, PUB chief engineering and technology officer. “At PUB, we firmly believe that technological advancements, delivered in partnership with academia and the private sector, hold the key to addressing the complex challenges posed by climate change.”

Electrochemical reactors for the Equatic process: These systems induce a series of chemical reactions that break down water into its hydrogen and oxygen constituents, while trapping dissolved CO2 from the atmosphere in seawater in the form of solid calcium and magnesium-based materials (Image: Satheesh Kumar Raman)