Powering our future with Canada’s rivers and tides
In the transition away from fossil fuels, Canada needs to look at every available renewable resource.
To meet the climate challenge, Canada needs plenty of clean and renewable electricity. Tidal and river stream technologies will help power our nation’s ongoing shift to climate-friendly, emission-free electricity.
Tidal stream technologies generate clean energy from the natural ebb and flow of the tide—similar to the way wind turbines work on land. River stream technologies use very similar technology; they harness river currents to spin turbines and generate clean electricity.
Marine Renewables Canada has designed this website to share information about these new technologies and the role they can play in Canada’s transition to a cleaner energy supply.
How They Work
Tidal and river stream generation technologies use a variety approaches to harness the power of moving water. Some float on the surface of the water; some are placed on the bottom. Some resemble wind turbines; others use drag to generate electricity.
Unlike dams, which span entire waterways and force water through a turbine, tidal and river “stream” devices use the natural, passive flow of water – the currents.
Tidal stream technologies tap into the energy of ocean currents—specifically the ebb and flow of the tides, which rise and fall twice a day. They rotate when the tide rises, generating electricity, pause at slack tide, and rotate again when the water flows in the opposite direction.
River stream technologies work in much the same way: The installation team anchors the technology, in the main flow of a channel. The electricity travels via cable to a nearby facility on the riverbank where it is either directly distributed to a community or stored in batteries.
Both technologies represent a big opportunity for Canada.
First, let’s pull back and look at the bigger picture.
To confront climate change, we need to convert just about everything that currently runs on fossil fuels—vehicles, buildings, factories, and more—to use emission-free energy instead.
While efficiency will be very important, every credible study of this transition concludes we will need a great deal of new clean electricity to meet the additional demand. Canada will need to generate upwards of two to three times the amount of clean electricity currently being generated in order to meet our net-zero by 2050 target.
While solar, wind, and hydro will generate much of that new clean electricity, Canada must consider the full sweep of renewable resources, technologies, and solutions available to us, including tidal and river stream energy.
Tidal and river stream energy can allow for greater uptake of more intermittent resources like onshore wind and solar because they are more energy dense, more predictable, and more reliable. This reduces the need to build new grid infrastructure and battery/smart grid storage. They can also provide power to other ocean industries like aquaculture and marine transport.
Despite its abundance, reliability, and near zero carbon emissions, river and tidal stream energy has, to date, largely flown under the radar in Canada. As the scale of our climate challenge becomes clear, it’s time for that to change.
Building tidal and river stream energy projects can result in many benefits for Canadians.
By helping eliminate or reduce fossil fuel generated electricity, tidal and river stream technologies address the leading cause of climate change. This will in turn help reduce its impacts, including ocean acidification and increasing ocean temperatures. Climate change is already impacting marine and coastal fish, animals, and ecosystems in Canada and beyond, and will continue to do so into the foreseeable future. It will impact not only ocean ecosystems, but also the industries that responsibly harvest fish, shellfish, and crustaceans.
Tidal and river stream energy not only produce clean electricity, it can create new jobs and business opportunities. Canadian suppliers that have historically worked in offshore oil and gas, defence, and other ocean sectors are already finding new opportunities in tidal and river stream projects here and internationally. For example, more than 300 local suppliers have supported tidal energy projects in the Bay of Fundy.
While the potential for tidal and river stream energy is enormous, the industry is just emerging, both in Canada and around the world. To date, there has been a little over 35 megawatts of tidal stream projects demonstrated, which is roughly what would be needed to power 22,750 Canadian homes. But this is only scratching the surface. Theoretical estimates for tidal energy show that there could be up to 1,200 terawatt hours of electricity available – enough to power 100 million homes around the world.
Canada is not alone in pursuing this clean energy opportunity. Australia, Finland, France, Ireland, Italy, Portugal, Spain, Sweden, United Kingdom, and the United States of America have all been active, and over 30 countries worldwide have tidal and river stream energy projects and research underway.
Although the sector is still in early stages, the international scientific community has already begun significant work around environmental effects monitoring and research.
Recently, a global coalition of marine renewable energy research organizations published the 2020 State of the Science Report, the definitive study on the subject of environmental impacts of marine renewables such as tidal stream power. Lead author of the report, Dr. Andrea Copping, an oceanographer with the U.S. Department of Energy’s Pacific Northwest National Laboratory, made the following general comments regarding the 2020 report:
We believe that small numbers of operational marine energy devices are unlikely to cause harm to marine animals, including marine mammals, fish, diving seabirds, and benthic animals; change habitats on the seafloor or in the water significantly; or change the natural flow of ocean waters or waves.
Despite our findings, we still need more data about what might, or might not, happen to animals swimming close to operating turbines underwater. In the years to come, we will continue to focus our research on examining this issue and building our knowledge base to help progress this important renewable energy industry.
In addition, a 2021 study of harbour porpoise behaviour suggests they easily navigate around a turbine a tidal energy site in offshore Scotland. According to the study, the data show that porpoises effectively avoid the turbine rotors, with only a single animal clearly passing through the rotor area while the rotors were stationary, and none passing through while rotating.
In summary, the environmental risks to marine life appear to be low, but still require attention. Industry and researchers working on projects in Canada continue to build knowledge on environmental effects through research and monitoring – aspects of development that are critical for advancing the sector safely and responsibly.
Want to Learn More?
Tidal and river stream technologies and projects
There are many different types of technologies being tested in Canada and internationally. Here are a few:
Industry and researchers have been working for years to ensure that tidal and river stream energy play a role in fighting climate change. These are some of the active organizations and initiatives in Canada where you can find more information on research and projects: