Abstract: Method and apparatus for converting the kinetic energy of a moving fluid stream into useful work by using a parallel cascade of aerofoils or hydrofoils positioned therein. The foils may be provided with at least two degrees of freedom and adjacent foils move in antiphase. The foils are subjected to resonant oscillations, known as flutter, induced by the fluid flow. Profiled inflow and outflow ducts may be positioned upstream and downstream, and the apparatus may be enclosed in a profiled duct, to increase efficiency by altering the fluid velocity and pressure. The foils are cantilevered, supported by vertical rods but are otherwise unattached. A cascade comprised of independent foil modules, each including a foil, a power conversion module and a motion control module, may be programmed to (1) receive energy from a fluid stream to generate power, or (2) transfer energy into a fluid stream to create propulsion or pumping.

Abstract: Method and apparatus for converting the kinetic energy of a moving fluid stream into useful work by using a parallel cascade of aerofoils or hydrofoils positioned therein. The foils may be provided with at least two degrees of freedom and adjacent foils move in antiphase. The foils are subjected to resonant oscillations, known as flutter, induced by the fluid flow. Profiled inflow and outflow ducts may be positioned upstream and downstream, and the apparatus may be enclosed in a profiled duct, to increase efficiency by altering the fluid velocity and pressure. The foils are cantilevered, supported by vertical rods but are otherwise unattached. A cascade comprised of independent foil modules, each including a foil, a power conversion module and a motion control module, may be programmed to (1) receive energy from a fluid stream to generate power, or (2) transfer energy into a fluid stream to create propulsion or pumping.

Abstract: A solar energy collector which includes a solar panel with channels for solar energy collecting fluid or liquid which channels are adapted to efficiently use the available panel area and thus more efficiently collect the solar energy per unit area than so far achieved. This solar energy collector comprises a solar panel distinctively including fluid channels tapering in width from an inlet end to an outlet end thereof and laterally juxtaposed such that the channels of one set laterally alternate with the other channels and taper in width in opposite direction relative to these other channels.