Underwater turbines spinning off the coast of Scotland for six years is a breakthrough in tide energy.

Submerged in about 40 meters (44 yards) of water off the coast of Scotland, the turbine has been spun for over six years to exploit the power of the electricity ocean tide. This is a durability mark that indicates the commercial viability of the technology.

According to the Trade Association’s Ocean Energy Europe, proper maintenance of large turbines in a fierce ocean environment for a long time paved the way for a larger tide energy farm, and is a much more attractive record for investors. Tide energy projects are prohibitively expensive if the turbines have to be removed from the water for maintenance every few years.

Tide energy technology is still in the early days of commercial development, but the possibility of producing clean energy is high. According to the National Institute of Renewable Energy, ocean energy is the term used by researchers to refer to electricity generated from tides, currents, waves or temperature changes, and is the world’s largest undeveloped renewable energy resource.

The Meygen Tidal Energy project off Scotland has four turbines each producing 1.5 megawatts, gathering enough power to power up to 7,000 homes a year. On Thursday, Swedish company SKF announced that bearings and seals on one of the turbines had passed the 6 1/2 year mark without the need for unplanned or destructive maintenance. We have worked closely with the industry for 10 years on design and testing.

According to Rémi Gruet, CEO of Ocean Energy Europe, achieving a 6-year water with a constant operation is a “very important milestone” and is a good thing for the future of tide energy.

Scotland and the UK are the global leaders of tide energy. The Meygen site, run by SAE Renewables, has been sending power to the grid for about eight years.

Few tide energy projects produce continuous electricity. Most of it was testing and demonstrations, said Andrea Copping, an expert in marine renewable energy development. Copping said there are still major hurdles to overcome before adopting tide energy more widely, including regulatory issues, potential environmental impacts and conflicts with other marine users.

Still, the Scotland project appears to be tackling the question of whether turbines can be sustained in seawater.

“I think they checked the box,” she said. “Skeptics, and of course investors and government, so it includes, ‘How are you going to run these things for so long in this very harsh environment?” And that’s what I think they have proved. ”

Meygen’s operations and maintenance manager Fraser Johnson said it is extremely difficult to ingest and place the wind turbines, which are essentially normally seen on land, under water. The record-setting turbines should have continued for at least another year before they have to come out of the water for maintenance, he added.

The four turbines are located in the inner sound of Pentland Firth, a narrow channel between mainland Scotland and Stroma Island, known for its strong currents. Tide energy systems require strong currents to make electricity efficient. Meygen plans to add 20 turbines to produce more electricity in 2030 after the power grid upgrade is complete. The site can ultimately hold 130 turbines, which are stronger than the turbines at today’s sites.

The Meygen site is located in open water, but another type of tide project involves creating dam-like structures called barrages that cross the waters of tide dal. With four turbines, Meygen is considered the largest tidal energy project of its kind worldwide, Johnson said.

“That’s a title we wish we had. I want more, I want others,” he said. “Unfortunately, others have difficulty achieving what Meygen has achieved. But we’ll work with SKF to move the industry forward.”

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