Tidal energy breakthrough: Six years of nonstop power sets global record

Tidal energy is clean and predictable, but harsh conditions, high maintenance, and technical challenges have made it hard to implement. But a new breakthrough in Scotland could change that.

SKF, a global engineering company, says its systems at the MeyGen tidal stream array have now run continuously for over six years without unplanned maintenance. According to the company, this is a world record for tidal turbine reliability.

This marks a major achievement for the MeyGen project, which is operated by SAE Renewables and remains the largest tidal stream array in the world. Located in the Pentland Firth off the northern coast of Scotland, the project is designed to test how long-term tidal energy systems can operate under real-world conditions.

According to the company, tidal stream power offers a reliable way to diversify the global energy mix. It also helps reduce carbon emissions, making it a valuable solution for future energy strategies.

Engineering the future of underwater power

SKF achieved this milestone by supplying high-performance components to turbines developed by Bristol-based Proteus Marine Renewables. These include specialized bearings and seals for the main rotor, yaw mechanism, and pitch systems. These parts are designed to operate reliably under water at depths nearing 100 feet (30 meters).

The MeyGen pilot array was commissioned in 2017, with turbines running continuously since 2018. This long-lasting performance without needing major repairs is exactly what the tidal energy industry has been working toward.

“We need suppliers that understand the demands of the subsea environment, where the consequences of key component failure are impactful. SKF has played a significant role in Proteus’ ongoing refinement and risk reduction efforts, and the input goes well beyond the supply of individual components,” said Drew Blaxland, CEO of Proteus Marine Renewables.

The next step is even bigger. The Swedish company will provide fully integrated 3MW powertrains for Proteus’ new AR3000 turbines. These are set to be deployed starting in 2026, with 30 turbines planned across sites in Scotland, France, and Japan. Each turbine will produce enough energy to power about 3,000 homes. Proteus hopes to expand to 300 turbines in the near future.

“The successful operation and performance of our existing turbines have proven the reliability of this technology and its potential as a predictable source of renewable energy. We are excited to collaborate with Proteus Marine Renewables with the support of SKF as we progress from a pilot project to full commercial deployment,” stated Fraser Johnson, O&M Manager for the MeyGen tidal array.

Market growth, global potential, and the road ahead

Tidal stream energy is unique in its predictability. Unlike solar or wind, tides follow consistent cycles. The challenge lies in engineering turbines that can survive turbulent underwater flows and strong currents over many years. SKF and Proteus appear to have cracked that problem with the MeyGen array.

This progress arrives at a time when the UK is targeting the deployment of 1 gigawatt of tidal stream capacity by 2035. That would be enough to power approximately 829,000 homes. According to Offshore Renewable Energy and Imperial College London, this sector could generate £17 billion in value and create 15,000 jobs in the UK alone.

The global tidal energy market, valued at $1.3 billion in 2023, is expected to grow to $8.1 billion by 2030. As the cost of tidal stream continues to fall, it’s on track to become competitive with nuclear power within a decade.

Still, the challenges are far from over. Suitable sites for tidal projects must have a strong tidal range—at least 13 to 16 feet (4 to 5 meters). One of the most extreme examples is the Bay of Fundy in Canada, with tidal ranges reaching up to 50 feet (15 meters). While rich in energy potential, this site has destroyed numerous turbines in the past due to violent tidal flows.

The speed of the water is also key. Tidal streams of around 6 knots (11 km/h or 6 mph) can put significant pressure on turbine components. This is why SKF’s durable bearings and seals, proven to withstand these forces, are a turning point.

According to Blaxland, “Validated estimates suggest that there is about 100 GW of exploitable, near-shore tidal power around the world, with 15 GW in Europe.” That’s enough to power 15 million homes in the region.

The long-term affordability of tidal energy still depends on the levelized cost of energy (LCoE), a metric that tracks the average cost to generate electricity across a turbine’s lifetime. If Proteus’ AR3000 turbines meet expectations tidal energy could join solar and wind as a key clean power source.