A
turbine integrated within a hydrofoil extracts energy from a free-flowing motive fluid. In the preferred embodiment, the
turbine is of the crossflow variety with runner blades coaxial to the width of the hydrofoil. The foremost edge of the hydrofoil comprises a slot covered by a continuously adjustable gate for controlling the overall drag imposed by the
turbine. The hydrofoil mounts to a sailing vessel by means of a
gimbal on a structure affixed to the
hull, enabling the turbine to optimally respond to changes in direction of the free-flowing motive fluid and facilitating guidance and stability of the vessel. Both axes of the
gimbal have a combination of auxiliary generator and motor with a
locking mechanism. Engaging the motor and
locking mechanism controls the guidance and stability of the overall vessel, and the
pitch of the hydrofoil. Disengaging the
locking mechanism and motor permits any change in direction of the motive fluid to affect the
gimbal thereby extracting energy via the auxiliary generators. To further control drag and output
power over a range of flow velocities, the preferred turbine comprises a DC generator with
voltage feedback controlling field excitation, coupled to a
voltage and current regulating circuit that performs
electrolysis of water to produce
hydrogen fuel. The
hydrogen fuel tank also functions as the vessel's
ballast having adjustable draft depending upon its fullness. Integrated
remote control simultaneously optimizes vessel guidance, velocity, drag, stability,
ballast depth, and
electrolysis processes.