An experimental investigation to measure the performance of a first prototype of a kinetic turbine is presented. This turbine, developed using numerical simulation, recovers the kinetic energy of water in free surface canals. To assess the performance of the machine, a first prototype as well as an open-air platform were built, both installed in the tailrace canal of Lavey hydropower plant. This is the first time in Switzerland that on-site experiments have been carried out for kinetic turbines. An experimental procedure was set up using measurements in the laboratory and on site to assess the power coefficient of the turbine as a function of the tip speed ratio. The influence of the turbine depth and the tilt of the turbine axis were also explored. A maximal power coefficient of 0.93 was reached for the higher tilt and depth investigated.