A massive tidal turbine said by its maker to be the world’s largest has started generating power.

Linked to the European Marine Energy Centre in Orkney just off mainland Scotland, the 74-meter-long, 680-ton O2 turbine will harness the power of ocean currents to meet the annual electricity demand of around 2,000 U.K. homes over the next 15 years.

The new tidal turbine is located in a body of water among the islands that make up Orkney and is connected to a land-based electricity network via a subsea cable.

Orbital Marine Power, the company behind the O2 turbine, said the huge piece of hardware is its first commercial turbine and the result of 15 years of development work. It was constructed in Dundee before being transported 200 miles across water to its current location.

The turbine’s floating platform is moored by anchors in a powerful tidal stream though it can also work with strong-flowing rivers, with underwater rotors capturing the dense flowing energy that passes through.

Here we can see the O2 tidal turbine entering the water for the first time.

Another video captures the recent installation process.

This animation offers a more detailed look at the machine’s structure and also a view of the two turbines that work beneath the water.

Commenting on the launch of the hefty bit of kit, Orbital CEO Andrew Scott said, “This is a major milestone for the O2 and I would like to commend the whole team at Orbital and our supply chain for delivering this pioneering renewable energy project safely and successfully.”

Scott added, “Our vision is that this project is the trigger to the harnessing of tidal stream resources around the world to play a role in tackling climate change whilst creating a new, low-carbon industrial sector.”

A CNBC report earlier this year highlighted how Scotland is becoming a hub for marine power, with Orbital one of several companies keen to exploit the strong waves and tides found in the nation’s waters.

The report also notes that while today’s market for marine power is small compared to other renewable technologies such as solar and wind, this looks set to change as countries around the world seek more paths to green energy.