Reaction Ferries have been in constant use around the world for over 500 years. In Canada there are 14 still operating today.
Reaction ferries have long been deemed ‘environmentally Friendly Transport Systems’ by all environmental groups. They are proven NOT to cause harm to marine life.
There are two Reaction ferries currently operating on the Fraser River in British Columbia, Canada today. These Reaction ferries operate at Lytton, BC and another (72km west) Clinton, BC. There are additional Reaction ferries on the Skeena and Thompson rivers.
What is important to note about the Fraser river Reaction ferries is that they operate on a fishery treaty protected river; if the two long operating Reaction ferries were harming or in any other way detrimental to rearing salmon, they would have been decommissioned decades ago but both are still in use today.
The videos below show two different variants of the core Reaction ferry approach in operation. Note the extreme simplicity of both systems. The single position retention line (pendulum approach) is ideal for some sites, while the ‘overhead cable and trolley roller system’ is ideally suited for other sites. Both installation systems have ultra low direct operating cost of less than 2 cents per hour, and they achieve the same function; they facilitate full cross-flow access of the ferry – without impediment surface traffic/navigation.
Both the retention systems shown are easily adapted to ‘kinetic-to-mechanical’ energy conversion.
Converting the ‘Reaction ferry’ approach to an exclusive electricity generation application, would simply mean replacing the ‘vehicle or passenger carrying’ portions of the systems with an appropriately optimized floating hydrofoil array. By adding (many) more hydrofoils and by increasing the translational velocity of the array, a considerably higher coefficient of power (Cp) can be achieved. The result is the ability to harvest considerable kinetic/mechanical energy, which can then be turned into ultra low cost electricity. It will be possible to retain the identical (ultra low cost) system retention infrastructure for generation application.
Using the Lytton, BC Reaction ferry example, our energy calculations showed that it could be possible to harvest as much as 2 megawatts (of instantaneous output) at this very location if the appropriate system modifications were made; see animation at bottom of page. The cost per kilowatt installed (a.k.a. cost of the required installation infrastructure) to harvest this amount of output, could be well less that a million dollars (CDN).
There is no technical reason as to why Shuttle foil kinetic energy harvesting systems could not be installed across tidal flow straits. For wider tidal flow straits of several kilometers, ‘semi-floating/submerged’ systems could be used. This type of installation would also allow for unimpeded surface navigation.
The harvest potential for such larger tidal flow systems would easily be into the high 10s of megawatts per system.
Short succession multiple harvesting installation potential:
Since gravity is ‘the energy source’ for flowing water, which of course continually causes the water to flow ‘down hill’, and regardless of any ‘momentary flow impediments’ caused by the harvesting array, the water will always ‘re-energize’ itself quickly after having passed through the harvest plain of a Shuttle Foil system, meaning it will be possible to install a number of Shuttle Foil systems in relatively short succession, i.e. within ’10s of meters’ of each other, to again allow harvesting from the re-energized flow.
Such tidal flow Shuttle Foil ‘Farms’ could easily have a ‘placarded output’ of into the 100s to megawatts each.
When temporary energy storage systems are added to each ‘SF Tidal Flow Farm’, highly reliable, ultra low cost electricity could be produced.
Temporary energy storage systems could include ‘HydroStore’-type systems (sea floor attached inflatable high pressure air systems), pumped hydro installations (long in use around the world) etc.
Compressed air (CA) storage is an ideal storage means. CA has long since served as a means of both storing and transporting mechanical energy. Aband0ned coal or salt mines/caverns are ideal. Even long distance pipelines are suitable to both store and transport CA energy.
All marine (and or wind for that matter) Shuttle Foil systems are slow moving, hence, they present little if any hazard to marine life large or small.
The first video below shows a Reaction ferry located at Rathen, Germany on the Elbe River; it employs the pendulum approach.
There has been a Reaction ferry in operation at Lytton, BC for over 100 years
A simple visual example of a ‘dual acting’ Shuttle Foil system in action, actual systems use additional cable loops
A recent water flume test showing a scale model making electricity. Note the light on the left side of video. A follow on flume test, a slightly larger model momentarily made 6 volts and 1 ampere at a 0.4 meter per second flow. The harvest area was (only) 0.4 square meter. Flow rate was between .38 and .5 meters per second. This test can easily be replicated by just about anyone.