Wave & Tidal Energy Primary Drives


Turbine PTO, Direct Drive PTO & Monoradial PTO 


  Inventor, John Clark Hanna, introduces three wave energy converters for utility-grade power:  (1) the Hanna Turbine known as a WETGEN (Wave Energy Turbine GENerator), U.S. Patent No. 8,358,026, (2) the Hanna MultiDrive, a mechanical, direct-drive power take-off (PTO), U.S. Patent No. 8,745,981 and (3) a mono-radial impulse turbine PTO.


  All three devices harvest energy from ocean waves by means of the OWC (Oscillating Water Column) principle.  OWC technologies are the most mature and well-studied wave conversion systems in the industry.  Oregon State University (OSU) built a small working Hanna Turbine.  The device was tested with a bi-directional air flow.  Acting as an impartial third-party, the OSU College of Engineering issued a final report that validated the Hanna Turbine in 2014.


  The simple and robust Hanna Turbine was designed to improve upon the pioneering Wells Turbine.  In contrast to the thirty year old Wells design, the transformative Hanna Turbine uses asymmetrical airfoils with a lower angle of attack.  This creates more lift and less drag.  The design resists "stall", improves self-starting and can function over a wider bandwidth with higher torque values.  It offers lower damping (restriction) to the bi-directional airstream.  Unlike the Wells, it drives two generators - doubling the power output.  Both generators are easily accessable and operate in a dry environment.  The Hanna Turbine is versatile, offering three distinct power take-off designs to meet job-specific applications. 


   The turbine and direct-drive devices operate at sea or on shore.  They can be built into existing or purpose-built jetties or breakwaters and can be easily connected to the grid.  All completed EIR studies for existing shore based OWC installations have resulted in FONSI (Findings of no Significant Impact).  Hanna shore based power plants will not interfere with marine life, maritime traffic, commercial fishing or recreational activities.  The buoys can be easily serviced through weather-tight hatches.  No generating components are immersed in water. 


  To underscore the remarkable versatility of the WETGEN design, the turbine can be easily modified for use as a tidal energy converter.  Whether applied for wave energy or tidal energy, no other turbine in the global marketplace can serve both of these renewable energy sectors.


  To provide reliable power for littoral and deep water research and data acquisition buoys, Hanna has developed a novel, patent pending closed-loop, one way drive for bi-directional air flows.  For details, click HERE.


   The patented MultiDrive  wave energy converter will spin multiple generators or seawater pumps.  For a more detailed description of the Hanna MultiDrive power take-off, click HERE . 


  In February 2019, a new US provisional patent 62/918,741 was granted to John Hanna titled: "Improved Volumetric Air Flows For Oscillating Water Column Turbines".  The invention provides a multi-fold increase in the volume of air that is drawn through OWC turbines.  The method greatly improves the efficiency and power output for all types of OWC turbines.


  To assure the responsible development and successful commercialization of all Hanna technologies, the inventor seeks to transfer his patent(s) to a qualified developer or manufacturer.


For an overview of both the Hanna AIR and TIDAL Turbines and to read two Master's degree Technical Reports, click HERE.

Test stand and early experimental Hanna Turbines


  Two Master's Dissertations on the Hanna Turbine have been completed.  The studies were undertaken at prestigious international universities.  The favorable results of both studies have advanced the turbine's Technology Readiness Level to TRL 4.  Please go  to Page 2 to read both Technical Reports.


  Still active is a call for an MSc or PhD-level candidate to pursue a dissertation on either the Hanna direct-drive PTO or the tidal energy PTO. Please respond to this call if you would like to conduct an original study of either of these primary drives.