Energy Procurement, GHG Emissions, Industrial  -  August 21, 2023

DOE, Federal Agencies Aim to Remove Marine Carbon Dioxide

A large partnership between federal agencies including the U.S. Department of Energy’s Pacific Northwest National Laboratory - Sequim (PNNL-Sequim) and the National Oceanic and Atmospheric Administration’s Pacific Marine Environmental Laboratory (NOAA/PMEL) is working to remove marine carbon dioxide.

The agencies are working with Ebb Carbon, a climate technology startup founded by former Google X, Tesla, and SolarCity executives. The company installed and began operating its first marine carbon dioxide removal (mCDR) and ocean deacidification system at the PNNL facility in Sequim, Washington.

Other agencies involved include the NOAA Cooperative Institute for Climate, Ocean, and Ecosystem Studies (CICOES) and the Salish Sea Modeling Center, both at the University of Washington. 

Funding is partly being provided by the NOAA Ocean Acidification Program (OAP), the U.S. Department of Energy’s Water Power Technologies Office (WPTO), and the ClimateWorks Foundation. 

Ebb is partnering with ocean monitoring and modeling institutions to gather and publicly share data about its technology. This approach is generating scientifically validated data that will provide visibility into Ebb’s carbon-removal process.

Ebb's first system, which is roughly the size of a shipping container, processes seawater that is pumped into PNNL-Sequim's marine lab from Sequim Bay. The seawater passes through a series of membranes, which act like a filter by removing acid from the water. Once the acid is removed, the seawater can absorb additional carbon dioxide from the air and store it as bicarbonate in the water. Bicarbonate is a durable and naturally abundant form of carbon storage in the ocean.

Before returning to the ocean, the treated seawater will be held in open air tanks to facilitate research, experimentation and simulation to document the impacts of the process on CO2 sequestration, ocean deacidification, and local biology. The treated seawater will return to the ocean through PNNL's existing wastewater system in accordance with existing permits. The research team is also evaluating the potential to power the Ebb system using marine energy including energy from ocean waves, tides and currents, as well as salinity, thermal and pressure gradients.

Ebb’s system in Sequim Bay has the capacity to remove up to 100 tons of atmospheric CO2 per year but will operate at a reduced capacity to allow for research by Ebb and its scientific partners. The system is designed to run intermittently, allowing it to leverage intermittent, low-carbon energy by ramping up and down based on the availability of local renewable energy sources.

“We hope Ebb Carbon's technology could help remove CO2 from the atmosphere as well as ease ocean acidification locally,” said Brendan Carter, a University of Washington research scientist working with NOAA's Pacific Marine Environmental Laboratory on seawater carbon chemistry, in a statement. “We are excited to test the method at the PNNL facility.”