The invention disclosed herein comprises a system focusing water current into a relatively smaller diameter lumen, imparting vortical movement to the current, and directing the water vortex through an even smaller diameter lumen en route to turbine blades having long curved blades rotatable along an axis parallel with the lumen. Rotation of the turbine blades turns gearing interfacing with the circumference of the turbine assembly, to rotate a drive shaft connected to a generator.