CANADA

OCEAN TIDAL ENERGY IN CANADACanadian Tidal Resource Map There are numerous tidal resources along Canada's coastlines. The Bay of Fundy is the most practical to develop because it's location

close to an existing electricity grid and potential consumers.

Company/Organization - Nova Scotia PowerTechnology/Plant Name - Annapolis BarrageTechnology Genre - Tidal BarragePower take-off system - Straflo Turbine

The Annapolis tidal barrage was constructed across the river estuary in 1984 and has an annual output of 50GWh with the turbines operating on ebb tides only.

However the Annapolis barrage has a few environmental problems; the banks of the river are being eroded and a trapping zone has been created where several whales have been stranded behind the barrage.

Tidal Barrage

Tidal Barrage

Diagram below shows the working of a tidal barrage built on an estury :

Tidal EnergyHarnessing Tidal Energy: Barrages

One method for harnessing tidal energy is a barrage, or tidal barrier, which is very much like a dam. When the water level is higher on one side of the barrage than the other, water is allowed to flow through the turbines to generate electricity.

How a tidal barrage works During high tide the gates are closed and water is stored “upstream” of

the tidal barrage. As the tide falls, the water level on the downstream side of the dam drops. When it’s low enough, the valves are opened for water to flow from the higher, upstream side—through turbines—to the lower, downstream side. The movement of the water rotates the turbines to generate electricity.

Due to the design of the barrage, the reverse can also happen. When the tide reaches its low point and the water level behind the dam is at the low tide level, the valves are again closed and the tide rises again. Water rises on the “downstream” side and when the valves are opened, flows “upstream” where the water level is at low tide.

Thus, barrages can effectively generate power four times during the day—during the two fall and the two rising tides.

 There are only a few operational tidal barrages in the world. The Rance River in France and the Bay of Fundy in Canada have the only large-scale barrages in the world with generating capacities of 240 MW and 20 MW respectively. There is a small scale plant in Kislaya Guba, Russia which generates 400 kW. A few countries have plans for other future projects.

Tidal Current TechnologiesCompany/Organization - Clean CurrentTechnology/Plant Name - Clean Current Tidal TurbineTechnology Genre - Horizontal Axis Turbine - DuctedPower take-off system - Permanent Magnet Generator

Clean Current Power Systems Incorporated is a private Canadian company that develops technology to extract electricity from ocean tidal currents. Clean Current designs and licenses tidal energy technology that converts the kinetic energy of tidal currents into electricity with unprecedented efficiency. Features of the technology include high efficiency, simple design with one moving part, no drive shaft or gearbox, no surface structure, long service life, low capital cost, low maintenance costs and minimal environmental disturbance. Clean Current is a tidal energy success story.The unit has been designed to rotate only when the current velocities exceed 2 knots (1 m/s). This minimum operation velocity means that the rotor is spinning about two thirds of the time at a typical tidal current location (including Race Rocks). Another concern is the impact of the acoustic signature on fish and cetaceans in particular. The rotation speed of the turbine varies between 20 and 70 rpm depending on current speed and unit size. As a result, a very low frequency noise (<100 Hz) will be produced. Cetaceans are not sensitive to low frequency noise (peak sensitivity for Killer Whales is 20 kHz) and their echo communication is at a much higher frequency (10-80 kHz). The amplitude of the sound is anticipated to be low.

Tidal Current Technologies

Locations of clean current technology in Canada :•Vancouver•Victoria•British Columbia

Tidal Current TechnologiesEnvironmentally Friendly features of Clean Current Technology

Zero emissions of any kind, greenhouse or other.Direct drive eliminates the use of a gearbox and drive shaft, normally lubricated with hydrocarbons.Ducted blade tip prevents accidental injury to sea life that is trying to avoid the blades.The footprint of each turbine generator in a power farm is small.Strong currents carry many nutrients so that any sea life disturbed on the ocean bottom during deployment will quickly regenerate.The generator will emit a low frequency sound when it is operating and this frequency will not interfere with sea mammal communication. Clean Current's unique design has a large hole in the centre of the rotor. In commercial scale models this hole will exceed 4 metres in diameter. Fish and sea mammals that frequent fast moving waters are very adept at avoiding collisions and would normally swim around the unit. There is no suction involved so avoiding the unit altogether would be the normal situation. In the unlikely event that a fish or sea mammal entered the duct area the large hole provides an escape route.The turbine generator is mounted on a post and is not visible from the surface. A minimum clearance of 15 metres is provided to ensure that commercial navigation is not impeded.

Tidal Current Technologies

Company/Organization - Blue EnergyTechnology/Plant Name - Davis Hydro TurbineTechnology Genre - Vertical Axis TurbinePower take-off system - Unspecified

Blue Energy receives tidal power investment World Energy Research has signed an $500m agreement to finance a

200 megawatt (MW) commercial tidal power project being developed by Blue Energy Canada, Richmond.

"After exhaustive research, World Energy Research found several companies capable of producing small amounts of energy, but none on the scale of Blue Energy's Davis Tidal Turbine, which was developed specifically to harness tidal power on a large scale," says Chad Willis, Managing Director of World Energy Research.

Blue energy is the energy extracted from osmosis of salt and fresh water through a membrane. The difference in the salt concentration between seawater and fresh water across special modified plastic membranes produces electricity. The process is called reverse electro dialysis (RED) (or osmosis) and the waste product in this process is brackish water (salt and fresh water mixed).The technology of reversed electro dialysis has been confirmed in laboratory conditions but the cost of the membrane is currently stopping a larger scale commercial proof. A new, cheap membrane, based on an electrically modified polyethylene plastic may change this in the near future.But how much power can you generate? Even though only small currents are generated, cells of membranes can be stacked to increase the output. For example, in the Netherlands, more than 3,300 square meters fresh water runs into the sea per second on average. The energy potential is therefore 3,300 MW, based on an output of 1 MW/m3 fresh water per second.The Good Very Clean Very little spaced used. Reliable constant source of energyThe Bad Needs to have constant stream of fresh water so there may be limited

sites. Not quite here yet

How does this work?These special membranes will allow a process called osmosis. Through osmosis these membranes will let fresh water through, but not the salt in the water. So you can divide a tank in two separated by a membrane. Fill one side with fresh water and the other side with salt water. The salt concentration will naturally try to balance itself. As salt can not pass through the membrane, that means fresh water will travel through to try and make the two sides have the same salt concentration. Almost nothing will flow back the other way. So the water level in the salty side of the tank gradually rises above that in the fresh water side. One side higher than the other = potential energy which you can harness through turbines etc. Several companies are now working on commercially viable plants. As mentioned previous, the membranes were previously to expensive to make this worth while but new technologies have brought the cost down. One of the most exciting things to come out of this technology is the small space it takes up. Potentially a 250 kW plant will take up the space of about 1 shipping container.  

Tidal Current TechnologiesCompany/Organization - New Energy Corporation IncTechnology/Plant Name - EnCurrent TurbineTechnology Genre - Vertical Axis TurbinePower take-off system - Permanent Magnet GeneratorFrom New Energy's inception until the introduction of the EnCurrent line of products, the company's sole focus has been to provide a water-to-wire in-stream hydroelectric product that could be purchased off-the-shelf. Key to achieving this has been the company’s development program.The first phase of the development program was the fabrication of an initial development turbine, which was able to generate 3 kW of electricity in a 3 m/s current. Parallel to the fabrication of the turbine, construction of a pontoon boat was commissioned to support testing of the turbine. The pontoon boat was outfitted with an outboard motor and the initial testing and validation of the turbine was carried out in a still water environment, with the current generated by the outboard motor pushing the pontoon boat and turbine through the water. A synchronous generator was used to convert the torque generated by the turbine into electricity.The initial installation of the turbine was at the City of Calgary’s Bonnybrook Wastewater Treatment Plant. It was in this installation that the decision was made to abandon the synchronous generator for power generation in favour of a variable speed generator. The installation also provided other learnings which were incorporated into the system and validated with the development turbine.

Tidal Current Technologies The EnCurrent in-stream hydro turbines are a revolutionary addition to

the small-scale hydro power market. Their vertical-axis design prevents many of the installation hassles associated with other micro-hydro turbine designs. There is no need to build a diversion for a water inlet, or to install a dam or weir in the waterway, and no need to puzzle through the system design process to install the turbine.

Every EnCurrent turbine is sold as a complete "water to wire" package, including appropriate inverters for your system type. Grid-tie packages include a PowerOne grid tie inverter and wind interface*. Off-Grid remote packages include a PowerOne MultiMode interface inverter.

Cost EffectiveEconomic Payback in as little as two years Low capital investment Minimal on-site engineering or construction required No fuel costs or associated handling, storage or transportation Low maintenance costs - easily performed by local techniciansEnvironmentally Friendly EnCurrent is a ?run-of-river? technology so water is allowed to flow

naturally Units are ?fish-friendly? allowing fish to pass through the system

unharmed Emission free technology Limited footprint with no dams, flooding, or stream alteration

Wave power at various locations on the east coast of Canada

Wave power at various locations on the west coast of Canada

Ocean Wave TechnologiesCompany/Organization - College of the North AtlanticTechnology/Plant Name - Burin Wave Power PumpTechnology Genre - Absorber - PointPower take-off system - Pressurized Hydraulics

Many on-shore activities, such as aquaculture, heating, cooling, fire suppression, power generation, etc., require large volumes of water. This renewable energy device “Burin Wave Power Pump” is capable of pumping required volumes of offshore water for on-shore applications. The device is a combination of a semi-submersible buoy, attached to a fully submersible massive base through a piston/cylinder pump arrangement. The pump is equipped with in/out valves to direct the flow of water. The device uses the energy inherent in the wave motion of an ocean or a lake in which it is submerged, to pump water to the shore or platform for use. The wave action of the water body moves the small float to drive a pump while the massive base moves very little. This relative motion of pump float and buoy body is translated into a piston stroke which is used to displace water through appropriate piping to shore. The device is designed to operate in a near-shore (~1Km, water depth > 7 M) environment where waves heights are frequently > 1M. Although the total energy available is determined by the local wave regime, output pressure and flow rates can be changed to suit activities by modifying the dimensions of the pump body. This flow of water can be used to generate electricity through the use of low-head generators. Mainly located in Toronto.

Ocean Wave TechnologiesCompany/Organization - Syncwave Energy IncTechnology/Plant Name - Syncwave Technology Genre - Absorber - PointPower take-off system - Mechanical

This technology is based on capturing the motion differential between two dissimilar float structures. Power is captured by a hydraulic power take off. Units are 100kw and looking at the specifications, these floats are 30M in length. Syncwave are working with University of Virginia and Marinus Power of Houston to commercialize this idea.

Ocean Wave Technologies

SyncWave Energy Inc. (SEI) announces SyncWave Power Resonator, a radically new approach to capturing the energy in Ocean Waves with frequency-based technology. SyncWave is a free-floating, self-reacting point-absorber system that is expected to dramatically improve the economics of wave energy. The energy and climate change dilemma has highlighted the costs and impacts of conventional non-renewable and renewable energies. Ocean waves are a major renewable resource, eclipsing wind and hydro in potential. SyncWave's ultra-low impact, long-life, almost invisible, and highly productive electricity generation technology cuts the cost of wave energy down to levels affordable by consumers and industry today. SyncWave power could sell for as little as $US 5cents/kWh.

CANADAPresented By – Vishakha – IX-B Garima – IX-B Akshaydeep – IX-B Anupama – IX-B Preeti – IX-B