Tidetec and MJ2 technologies have developed the VLH Tidal concept. A low head tidal turbine intended for barrage application. Their main market is installation of turbines in already existing infrastructure, like barriers intended for flood protection, ship-locks, unused drydocks or other small tidal pools. Even retrofitting new turbines in old Tidal mills can be an interesting market, as the system requires a modest tidal head to function.

TECHNOLOGY

The VLH turbine is specifically engineered to operate at very low heads (1.5 – 4.5m) with a discharge of between 10-27 m3/s, and therefore is ideal for small scale tidal barrage application. The VLH turbine currently has over 90 installations, and is therefore considered to be a proven turbine. The VLH Tidal system provides a net positive business case at with an average tidal head difference of 3-3.5 meters. The VLH turbine is very suitable to Tidetec’s turning device, as it is very compact, and requires no inlet and outlet tube – this enables the turbine to be turned with only a simple frame with an axel, instead of the Tidetec turret.

ENVIRONMENTAL IMPACT

The VLH turbine is one of the most fish friendly turbines on the market. In addition, it has a very low visual impact, because of the compactness of the turbine, and it is almost completely silent due to a low rotational speed. Since our system focuses on already existing infrastructure and the VLH turbine requires very little civil works compared to other hydro turbines, the environmental impact is also low in this area. For enclosed pools with limited water exchange, our system has a positive environmental impact – enabling more water exchange between the pool and the sea.

WAY FORWARD

Tidetec and MJ2 are looking for the perfect demonstration site, and are already in discussions with some promising demonstration sites in France. If you know of any sites that can be applicable to our concept – please let us know on joachim@tidetec.com.

A good demonstration site is shown below (Le Havre Dry Dock):