Rise of Marine Energy

More than half of U.S. electricity demand could be powered by the ocean. That’s the opportunity identified by the Department of Energy.

Marine energy, generated from the natural movement of water (currents, waves, tides), is predictable and reliable, unlike wind and solar.

Even capturing a fraction of that potential could reshape national energy systems, in the U.S. and around the world.

Where are the top locations? A study by Florida Atlantic University found that east Florida and South Africa consistently show power densities above 2,500 watts per square meter. For context, that’s about 2.5 times higher than what’s considered an excellent wind resource.

(Funny coincidence, South Africa is where I grew up and Florida is where I live now!)

In my previous newsletter, I wrote about how more funding, tax credits, and policy are contributing to the momentum of marine energy in the U.S., with a focus on what it would mean for national energy security.

There are also other advantages. Because these systems often sit in or under the water, they don’t compete for land or obstruct views, and they can directly power blue economy infrastructure, from ocean sensors and desalination to offshore computing.

But marine energy is still behind wind and solar on cost curves because it hasn’t had the same investment runway. Plus, the ocean is a brutally unforgiving place to test early prototypes. And we still need more research on potential impacts to marine life.

It has to be developed with the ecosystem, not at the expense of it.

I spoke to former NOAA Senior Environmental Scientist Adriana C. Bejarano, a Climatebase fellow with me, who shared, “The development of a blue economy must be matched with responsibility. Just as in spill preparedness and response, anticipating and managing risks to the marine environment before they arise is essential. Responsible development means advancing the blue economy while safeguarding the ocean that makes it all possible.”

Our understanding of the impacts is still evolving, and I’m motivated by the many studies looking at how to mitigate our impacts, like this OES-Environmental 2024 State of the Science Report on Tethys, a knowledge hub about environmental effects of marine and wind energy.

So what does marine energy look like in practice? Here are three companies turning ocean motion into power:

Eco Wave Power places floaters on existing marine structures like breakwaters and port walls, and as the floaters move with the waves, hydraulic pressure generates electricity on land.

This opens the door to creating greener ports that generate their own electricity. They’ve already installed the first onshore wave energy project in the Port of Los Angeles.

Panthalassa is harnessing ocean energy out in deep water to produce cheap, clean power and use it to run compute at sea (yes, powering AI with ocean energy). They also plan to produce renewable fuels and bring them back to shore.

This quote by Arthur C. Clarke on their website speaks to the potential of what they’re building, ”How inappropriate to call this planet Earth, when it is clearly Ocean.”

ORPC focuses on free-flowing rivers and tidal currents with underwater systems that quietly generate electricity.

My favorite case study is with Alaskan village Igiugig, which used to rely almost entirely on diesel, an expensive and polluting power source. With tidal energy being generated in their nearby river the community’s diesel use dropped by 60–90%, saving costs and avoiding air pollutants.

The project has been running for three years now, withstanding the brutally cold winters and having no impact on the local salmon population.

I believe the future of renewable energy will include multiple sources like wind, solar, geothermal, and more, but that marine energy will start taking up a much bigger part of the pie.

The ocean covers 70% of our planet.
It’s constantly in motion.
And now we’re building the tools to tap into that power responsibly.

Thanks for reading Blue Tide. Because I’m based in the U.S., and specifically Florida, you’ll often see the newsletter view stories through this lens and highlight opportunities from the region. There’s so much happening in the ecosystem, and I’m excited to share it with you.

🦈 Zané