The Orkney islands are famous for the innovative use of green hydrogen, but green hydrogen can’t exist without partnering with renewable energy sources and when you’re a chain of small islands, most of that renewable energy comes from the sea. Now, the islands officially have another source of hydropower with the connection of a tidal turbine to the electricity grid.

The turbine, called the O2 tidal turbine, was designed and installed by Orbital Marine Power and at first, it looked like a ship anchored offshore. Looking more closely, however, you can see that it is in fact attached to the seafloor at a depth of 35 meters, steadily collecting energy from the tidal waters that pass it each day.

The device operates with turbines that turn as seawater rushes by. They work in both directions, capturing energy as the tides ebb and flow each day. This turbine generates enough renewable energy to power 2,000 homes a year, but the most remarkable aspect of tidal energy is its predictability. Unlike wind and solar energy, which rely on specific weather conditions to operate at full capacity, tides are completely predictable, meaning operators know exactly how much energy the O2 will generate on a given day. More or less powerful tides can be foreseen, making tidal energy the most reliable form of renewable energy out there.

So why isn’t everyone installing tidal turbines? Cost is a big factor. Right now, tidal energy is more expensive than other forms of renewables, but Orbital Marine Power and other companies are working to scale up the solution to bring down costs.

Image source: BBC