To utilise previous and present knowledge and experience into creating the device for producing electricity from slow moving water with a minimum of environmental impact.

Our previous technological knowledge was what Mr. Darrieus did in the 1930`s mixed with the experience that was accumulated over a period of time, working with related problems. The know-how acquired from the use of foils in the spare time, i.e. pleasure craft sailing was also vital.
We started research work with the model “Alfa” in a self-build backyard basin during the late 90’s and, with a government grant; this led to the building of ”Bravo” in 2000.

Principle

This picture is a CP image of a turbine with fixed foils. It shows how forces are generated on limited parts of the circumflex.

The WPI turbine has as its basis a standard Darrieus turbine, but with the help of electronic controllers, positioning devices and motors we made the worlds first Active Pitch Controlled Vertical Axis Water Turbine with an sensational yield as can be seen in a report from the Norwegian University of Science and Technology.

All foils, either in water or air, are governed by the same principles. To have a maximum lift they need to have the optimum angel of attack. The basic problem that WPI solved boiled down to find the exact path and control the foils accordingly.
Due to sparingly CTF analysis tools it was a long road, with testing and failures, before WPI solved this problem. Once this path was found we had to develop a system of positioning devices, electronic controllers and motors.

The unique combination of the technical equipment and foil technology and hence the yield give a WPI turbine that can produce electricity at competitive prices from renewable, environmental friendly, resources.

We built an indoor test basin in 2003 to be able to perform scientifically professional tests that could be quality controlled.
Together NTNU, SINTEF and WPI have done testing and scientifically proved that the WPI turbine has a yield of 50 % in a broad range of water speed. We tested also the dam factor and found it to be calculabel and negligent.

The results are fully documented in the official NTNU report.