Startup Raises $20M to Remove Carbon Using Ocean Phytoplankton

Scientists have figured out how to supercharge one of nature's oldest climate solutions, and investors are betting millions it could help save the planet.

Gigablue, a startup founded in 2022, just raised $20 million to expand its ocean-based carbon removal technology. The company uses microscopic phytoplankton, tiny plants that naturally absorb carbon dioxide through photosynthesis, to pull greenhouse gases from the atmosphere and lock them away in the deep ocean.

Here's how it works: Gigablue creates substrates made from naturally occurring compounds that act like floating gardens for phytoplankton. These microscopic plants absorb CO₂ from the air, convert it into biomass as they grow, then sink to the ocean floor where the carbon stays trapped for centuries.

The technology improves nature's existing process by 100 times. Oceans already absorb about a quarter of human-made carbon emissions through what scientists call the "biological carbon pump," but Gigablue's method dramatically speeds up that natural cycle.

Planet Ocean Capital, a venture fund focused on ocean and climate technology, led the investment round. The funding will help Gigablue deploy more carbon-capturing systems and prove the technology works at a larger scale.

The Ripple Effect

What sets Gigablue apart is its commitment to transparency and ocean safety. Every deployment includes rigorous monitoring using oceanographic data, water chemistry analysis, and deep-sea tracking tools to ensure the process doesn't harm marine ecosystems.

This matters because removing carbon from the atmosphere is no longer optional. Even as the world cuts emissions, scientists say we need to actively pull existing CO₂ out of the air to avoid the worst impacts of climate change.

Marine-based solutions like Gigablue's could become essential tools in reaching global net-zero targets. Unlike some carbon removal technologies that require massive energy inputs or new infrastructure, this approach works with ocean ecosystems rather than against them.

The company is already working on closing the second round of Series A funding, signaling strong investor confidence in ocean-based climate solutions.

As one ocean covers 70% of our planet's surface, harnessing its natural power to heal our atmosphere might be exactly the kind of thinking we need.