Renewable Energy from Tidal Currents

The Netherlands is a global leader in the generation of tidal power. Dutch company Tocardo, together with various other parties, constructed an innovative tidal installation in the Oosterschelde. Providing enough energy to power 1,000 households.

Neeltje Jans storm surge barrier

The storm surge barrier in the Oosterschelde which is listed in the Guinness Book of Records as the largest tidal barrier in the world.

Image: Rijkswaterstaat

Hans van Breugel, CEO of Tocardo, affectionately refers to water turbines as 'underwater windmills'. Van Breugel says, 'Tidal energy, together with other sources, such as solar and wind, are needed to meet sustainability goals. The beauty of this technology is that it hidden from sight. In addition, it provides the most predictable energy flow of all. Low tide and high tide – the cycle of the tides never stops.'

Turbines with low maintenance costs

Tocardo turbines have rotor blades that can be pitched 180 degrees, so they can use both flood current and ebb current. 'Simplicity was central to the development of the turbines', says Mr. van Breugel. 'We wanted to minimise the maintenance costs, to make the price per kilowatt hour as favourable as possible.'

Sustainable Energy Production Incentive subsidy for pilot

Tocardo spent 12 years developing these turbines. Hans van Breugel explains, 'In 2008, we installed an initial version in the drainage sluices of the Afsluitdijk causeway, at Den Oever. With the help of a regional subsidy, we conducted a pilot project with a capacity of 100 kilowatts. We are using the experience gained during that project to further optimise our technology. We added three more water turbines to the installation at Den Oever, and another plant is operating in the Marsdiep tide race.'

Largest tidal power plant in the world

Support for the construction of the tidal power plant in the Oosterschelde storm surge barrier was provided by the Stimulation of Sustainable Energy Production (SDE+) and the South Netherlands Operational Programme.

The narrowing of the Oosterschelde barrier creates a high flow rate of 4.6 metres per second. Mr. van Breugel explains, 'Over the next 20 years, we plan to demonstrate our knowledge and expertise by operating five 230-kilowatt water turbines. The largest chain of turbines in a commercial plant anywhere in the world.'

Exceeding 200 gigawatts

According to Hans van Breugel, this is just the first drop in an ocean of possibilities. 'Until 2020, we want to generate 100 megawatts of energy to power 100,000 to 150,000 Dutch households. But the export forecast for tidal power exceeds 200 gigawatts, a much greater amount. We could provide 10% to 20% of the world’s electricity requirements. If we are to do so, we must now capitalise on Dutch tidal technology by selling it as an export product.'

Exporting tidal energy technology

Tocardo markets its technology around the world. The company is also involved in the development of tidal energy projects in North America and Europe, including the Isle of Man in the UK.