A Swedish device that mimics the human heart to turn ocean swells into electricity has just cleared a hurdle that’s kept wave power sidelined for decades. CorPower Ocean’s C4 buoy has now passed the strictest safety test in the marine energy industry. The company behind it is now moving toward what could become the world’s first commercial wave power plant.
The CorPower C4 has become the first wave energy converter to earn a full certificate from DNV, the Norwegian firm considered the gold standard for offshore energy certification. The seven-year review covered everything from initial design to structural fatigue, manufacturing, and real-world storm survival. For an industry that has struggled for 50 years to convince investors, that stamp of approval matters – institutional funders typically won’t back marine energy projects without it.
“This is a historic milestone for CorPower Ocean and the sector,” says the company’s co-founder and CEO Patrik Möller. “It moves wave energy from being a promising technology to being a proven and bankable one. I am immensely proud of our team for making CorPower the first wave energy technology to pass this bar.”
CorPower Ocean
The C4 is a teardrop-shaped buoy 9 m (30 ft) wide, 18 m (59 ft) tall, and weighing around 100 tonnes (110 tons). The system is tethered to the seabed by a tensioned cable. As a wave pushes it up, the cable pulls it back down with equal force, like a stretched elastic band snapping to its resting point. That constant back-and-forth spins a set of wheels connected to a gearbox, which spreads the mechanical load across several smaller components rather than one central point, reducing wear. The spinning drives a generator, sending power to shore via undersea cables.
The clever part is the phase-control system, which CorPower calls WaveSpring, and which explains the heart comparison. Rather than resisting motion like a shock absorber, it works like a spring that amplifies it, similar to how a heart valve pumps in sync with blood flow. On calm days, a wave just 1 m (3.3 ft) tall can be amplified to move the buoy 3 m (10 ft), tripling the energy captured. During storms, the system does the opposite and loosens up, letting the waves pass through with minimal resistance and allowing the buoy to survive swells up to 18.5 m (61 ft) without structural damage.
CorPower Ocean
As with wind or solar, one buoy doesn’t generate much on its own. CorPower’s commercial plan involves clustering dozens of buoys into arrays called CorPacks, each capable of producing hundreds of megawatts. Enough to power hundreds of thousands of homes.
But unlike wind or solar, waves keep rolling around the clock, so the output is steadier. A predictability that comes from waves being built up by weather systems over several days across entire oceans, smoothing out the energy before it ever reaches the coast. That steadiness could allow wave farms act as a natural balancing source for the grid, reducing the need for the backup storage or excess wind and solar capacity that renewable systems otherwise require.
How it works- CorPower Ocean Wave Energy Converters
A prototype has operating off Aguçadoura in northern Portugal since 2023, sitting 4 km (2.5 miles) offshore at a seabed depth of 45 m (148 ft). Over three deployment cycles, it has run autonomously, fed power into Portugal’s grid, and survived Atlantic storms. Including a record 18.5-m (61-ft) wave logged during Storm Domingos in November 2023, according to Portugal’s Hydrographic Institute. Surviving that battering without damage is largely what convinced DNV to sign off.
CorPower is now moving toward its first two commercial-scale arrays, in Portugal and Scotland, aiming to establish wave power as the world’s third-largest renewable energy source alongside wind and solar. If these projects perform as promised when they come online by 2027-2029 , they’ll offer the first real-world proof that wave power can be a steady contributor to the grid.
“The issue of the first Wave Energy Converter Prototype Certificate was the culmination of a thorough and rewarding interaction with CorPower,” says Claudio Bittencourt Ferreira, Project Manager, DNV Renewables Certification. “It marks an important stepping stone in the realization of commercial wave energy. DNV has supported this sector for over 20 years and is familiar with the many challenges these devices face. The commitment shown by the CorPower team in achieving this milestone is impressive, and we look forward to continuing the journey with them.”
Source: CorPower Ocean
