Tidal power is a fantastic source of clean, predictable energy – if you can harness it. It’s proven immensely difficult due to a range of factors, but engineering giant SKF says it’s making major headway in this field. The company claims to have set a world record for tidal turbine reliability at the MeyGen facility in Scotland, with systems operating continuously for over six years without unscheduled maintenance.
That’s a big deal for this slow-growing energy sector, which involves numerous operational challenges including the constant need to service tidal turbines installed underwater in coastal areas with a high tidal range (the difference in water level between high tide and low tide at a specific location). Increasing the length of time between overhauls makes this technology more feasible to deploy and run over decades, without running up massive costs.
Here’s a quick recap of what we’re talking about with tidal turbines. Powerful tidal currents in bays, estuary entrances, narrow straits, and inlets from the sea turn underwater turbines that are connected to a generator to produce electricity. This system is predictable because tidal patterns are consistent and well understood.
Tidal power adoption has been slow thus far, mostly because it has specific site requirements (like being installed along coastlines with large tidal range of at least 13-16 ft (4-5 m), high upfront costs for robust infrastructure that can withstand harsh marine environments, and the potential impact on marine ecosystems.
The Bay of Fundy in Canada, which has the highest tidal range in the world (reaching up to 50 ft (15 m) and would make for an excellent source of clean energy for the region, has routinely been smashing tidal turbines to bits with its rapid tidal streams.
That’s why it’s important to choose a suitable location. But you also need machinery that can hold up against tidal flows that peak at roughly 6 knots (6 mph or 11 km/h).
To that end, SKF has been partnering with Bristol, UK-based energy company Proteus Marine Renewables to meet those demands. An array of Proteus AR series turbines with SKF-made bearings and seals have held up for six years at depths of nearly 100 ft (30 m) at MeyGen, the largest planned tidal stream project in the world.
SKF will soon supply 3-MW powertrains for Proteus’ latest and most powerful AR3000 turbines, 30 of which will be installed over the five years following 2026 at sites in Scotland, France, and Japan. Each of these turbines is designed to generate enough electricity to power around 3,000 homes. Proteus hopes to follow that up with 300 more turbines.
That could prove to be a major energy unlock for the regions that have the right conditions for tidal power. As of 2021, it was estimated that tidal only accounted for electricity to power just 400,000 homes worldwide – a drop in the ocean, if you will.
“Validated estimates suggest that there is about 100 GW of exploitable, near-shore tidal power around the world, with 15 GW in Europe,” said Proteus CEO Drew Blaxland. For reference, 15 GW works out to enough electricity for 15 million homes.
AR3000: World’s Largest Turbine – Powered by Proteus Marine Renewables
What remains to be seen is the levelized cost of energy (LCoE) – a measure of the average net cost of electricity generation for a turbine over its lifetime – this proven reliability helps Proteus arrive at with its next batch of turbines. That will play a huge part in determining whether tidal power will have more takers in the near future.
Source: SKF
