Waterotor – An Innovative breakthrough for harnessing energy from very slow moving water

Waterotor – An Innovative breakthrough for harnessing energy from very slow moving water

The small, rolling drum-like device called the Waterotor, created by Fred Ferguson, CEO of Waterotor Energy Technologies, is capable of harnessing energy from water currents moving at just one to six miles per hour and converting into electricity.


The Waterotor is ideal for the world’s energy requirement through renewable way because it transforms the energy in slow-moving rivers and ocean currents to electrical power, thereby making a continual stream of low-cost electricity available 24 hours a day to people and businesses not connected to a central grid. This unique hydro-turbine is the result of a multiyear R&D program conducted under the leadership of renowned technologist Fred Ferguson, recipient of numerous awards and recognition for his work in the aerospace and energy fields. 



Image credit: Waterotor

Waterotor Energy Technologies Inc., is an Ottawa, Ontario, Canada, based company incorporated in late 2010. The Notable aspects are that the Waterotor stands alone as a technology that simplifies the extraction of a high level of energy from very slow moving water. The technology can be scaled from small units to ocean sized rotors. Output estimates of electricity from water moving at 4 mph equates to a few cents per kilowatt hour. This technology has gone through multi-million dollar development and is now being commercialized for mass deliverables.


Image credit: Waterotor



Waterotor is unique in that its highly developed design can extract a very high level of energy (Coefficient of Power) from very slow flowing water. Waterotor stands alone by extracting 30 % of slow moving water energy and converting this energy to electricity at these very slow water flow speeds. No other water extraction device can effectively and cost efficiently operate in a flow speed of 4 mph ‘typically found in ocean currents and many river systems’. Also, the 30 % extraction rate is a constant from flow speeds as low as 1 mph.

Fundamental to the invention is the way in which the Waterotor achieves maximum torque resulting in a high coefficient of power. This relates directly to power vs. size vs. water flow speed. Ferguson’s early inventive understanding of the combined components and features regarding the W.E.T. 

Waterotor has been verified for maximum energy extraction for a water flow speed range from 1 mph to over 20 mph (size and generator match ‘selection’ per size and flow conditions). Efficiency rating is 24 % energy extraction to over 30% – about the maximum expected efficiency for a Savonius rotor.

Advantages of Waterotor
  • Operates in slow-moving water; as lower than 1.5 mph
  • Mobile, requires no bottom fixtures or foundation, only simple anchoring
  • Strong yet simple structural integrity (‘drum like’)
  • High coefficient of power (high-energy output vs. size)
  • Environmentally friendly (no high speed spinning blades)
  • Broadens a competitive market from very low to high water flow speeds
  • Most cost effective (simple to build and fully scalar)
The Waterotor-Generator is classified as a ‘low head’ system, meaning the flow is horizontal through the entire system. It is unique among all low-head systems in that it is the only device that is not an open propeller-like bladed turbine or ‘airfoil-like’ turbine. These bladed turbines accelerate in the flow to tip speeds higher than the flow itself.


Given the difference in density of water and air, a 3 mph ocean current has about as much kinetic energy as a 240 mph wind. Hence, a much smaller device is required to harness energy. From water flow than to harness wind energy. As oceans cover over 70% of the earth’s surface, ocean energy (including wave power, tidal current power and ocean thermal energy conversion) represents a vast source of energy, estimated at between 3,000 TWh (Terawatts), i.e. 2,000,000,000,000,000 watt hours per year. This is enough energy to satisfy a major portion of the world’s electrical needs.

The National Research Council recently selected the Waterotor for support under its highly competitive Industrial Research Assistance Program. Black & McDonald and other Canadian companies have helped to get the Waterotor ready for commercial production.

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