Sustainable energy with clockwork regularity

For centuries the Dutch have had a love-hate relationship with water. As large parts of the country are way below sea level, flood protection is always top of mind in The Netherlands. On the other hand, the abundance of water has led to an uninterrupted flow of innovations related to maritime transport and various forms of water management. Tidal energy is one of the most recent manifestations of this tradition – and also one of the most exciting. With Tocardo as its undisputed frontrunner.


Considering Holland’s ambivalent perspective on water, it is remarkable that many existing water safety structures turn out to be the perfect sites for tidal energy installations. Tocardo’s headquarters are only a stone’s throw away from the Afsluitdijk, built more than 80 years ago, but still an impressive milestone in the country’s continuing battle with the forces of the sea. Right here, these forces are now exploited in a positive way. Tocardo and its founding partners have been testing tidal turbines in the Afsluitdijk since 1999.

tocardo_portrait_image_1Storm surge barriers and tidal inlets provide a perfect natural environment for tidal energy installations. However, in search of additional sites and extended flexibility, Tocardo has developed a system which enables tidal energy installations to be set up offshore. A semi-submersible structure, held in place by a special mooring system, offers the possibility to extract energy from virtually every environment with sufficient tidal movement. This Universal Foundation System is now a standard product, ready for commercial rollout in 2017. Sjoerd Keijser, Commercial Director of Tocardo: “In The Netherlands we have adjusted our installations to a number of sluices, tidal inlets and flood barriers. At the Afsluitdijk for instance, but also at the East Scheldt storm surge barrier, part of the Dutch Delta Works. By now, this is proven technology. The next step will be to implement our Universal Foundation System on a larger scale. Near the island Texel, a tidal energy demonstration platform went from a sketch on the drawing board to a grid-connected installation in less than six months.”


“We are both equipment supplier and energy supplier. We sell our turbines to power plants and as a partner in this power plant we sell electricity to energy buying companies.”

Horizontal ax

Coming from a maritime and offshore background, the engineers of Teamwork Technology started Tocardo as part of a technology incubator, particularly focusing on harvesting energy from the tides. After an extensive research phase the horizontal ax turbine emerged as the most promising concept for further development. Sjoerd Keijser: “The horizontal ax turbine has a lot in common with a wind turbine. We sometimes call it an underwater windmill, because we have used a lot of mechanical systems from wind turbines. The blades are significantly smaller, however, as water has a much higher density than air. An important difference with wind energy is the cost of inspection and maintenance, which is relatively high in offshore situations. That is why we put a lot of thought into creating an installation that can function for twenty years without requiring a lot of special attention by mechanics.”

Sjoerd Keijser

Sjoerd Keijser, Chief Commercial Officer at Tocardo International

Equipment and energy supplier

Tocardo develops and manufactures tidal power turbines, but it also participates in energy projects, which produce and market electricity through power purchase agreements. Keijser: “We are both equipment supplier and energy supplier. We sell our turbines to power plants and as a partner in this power plant we sell electricity to energy buying companies.” In the near future, Tocardo will also offer service and maintenance solutions to tidal power plants. “In the maritime energy market, business as usual does not exist yet. But I expect that in the longer term we will focus on manufacturing and maintainting tidal power turbines. It’s what we do best.”

Although Tocardo is a relatively small supplier, the company has already made more turbines operational than any of its competitors. Sjoerd Keijser: “There are several reasons why we often manage to beat the competition. First of all, we are able to deliver. Our turbines work. Our products meet the highest possible technology readiness requirements. Moreover, we offer smaller turbines, which make us and our customers more flexible and resolute. We prefer to install four turbines of 250 KW instead of one 1MW turbine. Our installation is just as effective, but much more affordable. In the first quarter of 2017, we will be the first tidal energy supplier with a turbine type certified by DNV GL, which makes us all the more attractive for energy companies looking for a stable and reliable supply partner. Our technology track record in development and production is unmistakable.”

Tocardo turbines


Obviously tidal energy is not the only way of harvesting sustainable energy. However, the tides do have a remarkable advantage over other powerful sources like sun or wind. Whereas solar or wind energy are dependent on the weather, tidal energy is almost perfectly reliable and predictable. The tides are always there, day in day out.

Sjoerd Keijser is excited by Tocardo’s prospects – and not just because he has confidence in his own company’s qualities. “The global demand for energy will double within the next two or three decades. Whatever your view on climate or environment, fossil fuel reserves are finite. So the question is not if the energy transition will take place but when. And what renewable energy will look like. There’s no doubt the importance of solar and offshore wind energy will increase, but the predictability of the tides will make this form of renewable energy very attractive for both energy buyers and energy distributors. As soon as the turbines are operational, you know exactly how much electricity you get and when you get it.”

Tocardo Team


Tocardo Tidal Energy Ltd
Sluiskolkkade 2
1779 GP Den Oever
The Netherlands
T: +31 (0)227 726 200