A wave energy conversion cylinder includes an outer cylinder and a center rod disposed along an axis of the outer cylinder. A plurality of electrically-conductive windings are disposed about an inner circumference of the outer cylinder. A magnet is slidably disposed on the center rod. A buoyancy cylinder is disposed outwardly of the outer cylinder. A first moveable ring weight may be slidably disposed along the axis of the center rod and a second moveable ring weight may be slidably disposed along the axis of the center rod. The first moveable ring weight and the second moveable ring weight facilitate control to tune a mass moment of inertia of the wave energy conversion cylinder.

A thrust bearing wear pad includes a rigid support plate adapted to be mounted on a collar and under a thrust flange in a hydro power turbine system. Multiple lignum vitae wood blocks are fixed to the top of the support plate and act as a wear surface on the wear pad.

A thrust bearing wear pad includes a rigid support plate adapted to be mounted on a collar and under a thrust flange in a hydro power turbine system. Multiple lignum vitae wood blocks are fixed to the top of the support plate and act as a wear surface on the wear pad.

A wave energy conversion cylinder includes an outer cylinder and a center rod disposed along an axis of the outer cylinder. A plurality of electrically-conductive windings are disposed about an inner circumference of the outer cylinder. A magnet is slidably disposed on the center rod. A buoyancy cylinder is disposed outwardly of the outer cylinder. A first moveable ring weight may be slidably disposed along the axis of the center rod and a second moveable ring weight may be slidably disposed along the axis of the center rod. The first moveable ring weight and the second moveable ring weight facilitate control to tune a mass moment of inertia of the wave energy conversion cylinder.

An apparatus for generating electricity from water flow held behind a barrier includes a convergent section connected to a first end of a mixing tube such that a venturi is defined between the end of the convergent section and the mixing tube; a diffuser section connected to a second end of the mixing tube, the diffuser section configured such that the pressure at the exit of the diffuser section is greater than the pressure at the venturi; and a turbine tube comprising a blade assembly having a plurality of blades. The turbine tube is supported in the convergent section and is rotatably mounted, the blades being attached to the inner surface of turbine tube such that water flow past the blades drives the rotation of the turbine tube.

A rotating assembly adapted for use in turbines and pumps is provided. The rotating assembly includes a shroud that rotates around a central axis and a disk seated in a recess in the shroud so that the disk rotates with the shroud, the disk being oriented perpendicular to the central axis. The rotating assembly also includes a stationary element in which at least one surface of the disk contacts a fluid so that when the fluid flows under pressure, the surface of the disk resists the generation of drag between the surface and the stationary element of the rotating assembly. A shroud is provided that includes a circular recess with a cavity on an outer perimeter extending away from the fixed assembly. A method of manufacturing a rotating assembly is provided.

A marine turbine comprising a stator, a rotor, the rotor being able to be driven in rotation around an axis or rotation by a stream of a liquid, and at least one first bearing for supporting the rotor, the or each first bearing, comprising a magnetic stator element secured to the stator and magnetic rotor element secured to the rotor. The marine turbine further comprises at least one second bearing for supporting the rotor, the or each second bearing comprising at least one rolling element.