The path to net-zero emissions? Researchers look to the ocean

It sounds too good to be true: carbon dioxide being sucked up by the ocean and stored there, safely and without acidification, for more than 10,000 years. Yet, technology to do just that is being created here at UCalgary.

According to the latest Intergovernmental Panel on Climate Change’s (IPCC) Assessment Report, global surface temperatures have already reached 1.1°C above the pre-industrial period. Changes to the climate are happening in every region of the world, resulting in rising sea levels to extreme weather to habitat destruction and species extinction.

The IPCC says to hold the planet’s long-term average temperature to below a 1.5-degree threshold, the world will have to reach net-zero emissions by the year 2050, an objective shared by the Government of Alberta in its Emissions Reduction and Energy Development Plan.

So how do we reach net zero in just over 25 years? A group of UCalgary researchers are looking to the ocean — which takes up over 70 per cent of the earth’s surface and already naturally absorbs carbon dioxide from our atmosphere — for an answer.

The PEACH (Practical Electrochemical Air Capture and Hydrogen) DAC (Direct Air Capture) project is made up of a group of transdisciplinary researchers — in science, engineering and law — who are using electrochemistry to manipulate seawater alkalinity and capture carbon dioxide on a global scale.

“The ocean has a natural capacity to take more C0₂ from the atmosphere,” says Dr. Arthi Gopalakrishnan, PhD, an Eyes High postdoctoral scholar in the Department of Earth, Energy and Environment, who is working on the project.

Gopalakrishnan explains that the process will be relatively simple, from a theoretical point of view. The electrochemical cell she is developing (and already has a prototype for) will manipulate sodium ions within two regions of the ocean at different depths.

“When we enhance the alkalinity of the surface ocean, by moving sodium ions at levels that won’t impact biological ecosystems, the ocean will then take in more carbon dioxide,” says Gopalakrishnan.

Dr. Steve Larter, associate vice-president (research and innovation), is another member of the PEACH DAC group. He explains the process won’t add any harmful substances to the ocean, and that the C0₂ would be converted into sodium bicarbonate, which is mostly what an Alka-Seltzer is made of.  

Larter is one of several researchers at UCalgary who, in addition to supporting the Creative Destruction Lab (CDL) Rockies accelerator program, also plays a key role as a technical mentor in the CDL-Vancouver Climate. Larter recently won the CDL-Vancouver Climate Stream Scientist of the Year award.

“There’s so much inorganic carbon in the form of bicarbonate in the ocean already, that even if you took all the carbon dioxide out of the atmosphere and put it in the ocean as bicarbonate (which you wouldn’t want to do) it would make a very tiny difference to the ocean bicarbonate concentration,” he says.

PEACH DAC's mission is to have a significant impact on C0₂ levels globally. By 2026 they plan to have a small scalable module that can capture one tonne of C0₂ a year from the atmosphere. By 2033, or ideally before, they want to capture 100 tonnes annually. From there, they’re hoping to continuously scale up the infrastructure.

“Look at the technology as a set of LEGO,” says Larter. “At the moment, we’re trying to build one LEGO brick. We don’t even have the brick; we have the little stud on the brick. Once we have the whole brick, it will extract one to 10 tonnes a year of C0₂. Then you can stack a whole lot of bricks together to extract a thousand tonnes, or eventually, a million tonnes.”

The PEACH DAC group has a startup called PEACH DACquiri Inc. They believe commercialization is key to rapidly scaling up the project. Speed, they know, is key to fighting climate change.

“Being able to solve the problem is no good if we can’t do it fast enough. This is a mission-driven project, which is quite different from our usual research programs,” says Larter. “If this takes 20 years, and the next initiative takes 20 years, we’re hooped. We’re trying to do this project in a much faster way.”

And projects like this would help the economy, too. According to Carbon Removal Canada’s first research report, Canada's economy would gain 300,000 jobs and $143 billion in GDP by 2050 with a scaled carbon dioxide removal (CDR) industry.

Larter explains that to develop the technology quickly, the PEACH-DAC group is also looking for early CDR applications with existing oil and gas and geothermal industries.

“What makes it all possible is to have social innovation experts like environmental lawyer Anna-Maria Hubert on the team and to work within such a great innovation ecosystem team here at the university and Innovate Calgary,” he says. “This is not only a technical innovation, but also a social one. Solutions have to be acceptable and desirable by society if we’re going to achieve net zero.”

In the big picture, those working on the PEACH DAC project know this is one answer to an urgent global crisis. And they know the solutions we come up with in the coming years will have a massive impact on our children, grandchildren and the health of the Earth.

“Basically, we’re trying to do our little bit to save the planet and ourselves,” says Larter. “But this problem will need many, many other solutions as well.”