When you think about renewable energy, you think about solar, wind or hydro, but rarely about tidal energy, which is technically a form of hydropower. That’s because the modern version of the technology is still in its infancy and the deployed capacity is very limited.
But there has been a significant advancement this month with a single massive tidal turbine being deployed on the coast of Nova Scotia, Canada – a first in North America.
I say that the modern version of the technology is still in its infancy because tidal energy has actually been used in its crudest form for thousands of years. In Ancient Rome and in the Middle Ages, people contained water in large storage ponds on the coasts and as the tide went out, it turned waterwheels that used mechanical power to mill grain.
Now the technology is used to power turbines and generate electricity.
There are only a few projects in operation around the world, but several more are currently in development, including the Cape Sharp Tidal in the Bay of Fundy in Nova Scotia, Canada.
Earlier this month, the developers, OpenHydro and Emera, deployed the first of a series of massive turbines and connected it to the local grid yesterday.
It’s actually the second attempt to deploy the system. In 2009, they deployed the first version of the turbine, but the blades were destroyed by the powerful tides.
It’s important to note that the Bay of Fundy is renowned for its strong tidal range, one of the highest in the world with a recorded 17 meters (56 feet). An estimated 115 billion tons of water flow in and out of the bay during the tidal period.
The group went back to the drawing board and developed a stronger turbine to harness that power.
The turbine is five-storey high and weighs roughly 1,000 tons.
Another turbine should also be deployed in the coming months for a total of 4 MW. The group wants to ramp this up to 16 MW by the end of 2017.
Under its current form, the project is only really a demonstration and test of the technology since it’s in no way economically viable otherwise. The cost of MWh delivered is roughly $530 or $0.53 CAD per kWh.
In comparison, Nova Scotia Power, one of the companies behind the project, delivers electricity at a standard rate of 14.800¢/kWh.
Nonetheless, the current turbine generates enough electricity to power 500 homes and as the technology matures, it could be streamlined and drop down in cost significantly.
An important part of the cost is attached to the development of custom tools and logistical equipment to build and deploy those massive turbines. Once the cost of the development of this equipment is amortized over several more turbines, it will start making more sense in term of cost of energy delivered to the end-user.
If the project is successful and doesn’t affect marine life as the developers claim, it will be interesting revisit their cost of kWh delivered in 2020 when they expect to have about 300MW of capacity deployed in the Bay of Fundy – serving nearly 75,000 customers.