An improved prediction model for in-stream water wheel performance

As global efforts to decarbonise industries continue, there is increasing pressure to identify and proliferate sustainable methods of generating electricity, in-line with the United Nations’ Sustainable Development Goal 7. The in-stream water wheel is a pico-hydropower technology that generates electricity using only the kinetic energy in the fluid, rather than both potential and kinetic, like most forms of pico-hydropower. Current methods of estimating the power output of these turbines lack validation, robustness and proper justification for their assumptions. This study has developed a new method for predicting the power output of in-stream water wheels, based on fluid dynamics principles, and has been compared with a range of experimental results to confirm its robustness. The new model identifies novel characteristics of the power stroke of the turbine blade, including unsteady effects and negative torque production at certain blade angles. In addition, the model can be tuned to match experimental data, improving its accuracy in specific applications. The better prediction of power output aims to encourage the use of in-stream water wheels as part of the global decarbonisation strategy.